bivalirudin and Thrombosis

Bivalirudin has been suggested as an alternative to heparin for anticoagulation in patients receiving extracorporeal membrane oxygenation (ECMO). Nevertheless, there is limited evidence about the benefit of bivalirudin in ECMO patients compared with heparin. Hence, we conducted a meta-analysis to assess the effect of bivalirudin versus heparin on clinical outcomes in patients receiving ECMO.. PubMed, Embase, and the Cochrane Library were systematically searched from inception up to 1 April 2022 for cohort studies and randomized controlled trials comparing bivalirudin versus heparin in patients who received ECMO. The primary outcome was short-term death. Secondary outcomes included thrombotic events and bleeding events.. We selected 12 retrospective cohort studies with 1232 ECMO patients focusing on bivalirudin anticoagulation (n = 497) versus heparin anticoagulation (n = 735). Two hundred and one of 497 patients (40.4%) in the bivalirudin group versus 350 of 735 patients (47.6%) in the heparin group did not survive to hospital discharge. Compared with the heparin group, bivalirudin anticoagulation did not significantly decrease in-hospital mortality in patients receiving ECMO (RR, 0.95; 95% CI, 0.79-1.13;. Compared with heparin anticoagulation, bivalirudin did not decrease the rates of short-term mortality and thrombotic events, but reduced the incidence of bleeding events in patients receiving ECMO.

Topics: Anticoagulants; Extracorporeal Membrane Oxygenation; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombosis

Extracorporeal membrane oxygenation (ECMO) poses unique thrombotic and hemorrhagic risks, and the optimal anticoagulant choice is unknown. We systematically searched Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus, and Web of Science Core Collection for randomized-, crossover-, retrospective cohort-, or parallel-designed clinical studies of adult patients receiving ECMO that compared heparin recipients with bivalirudin recipients. Meta-analysis was performed with random-effects models. The ROBINS-I tool was used to assess the risk of bias. Six retrospective observational studies met the inclusion criteria for the qualitative summary. Five studies were suitable for meta-analysis. Those who received heparin were more likely to experience circuit-related thrombosis (odds ratio [OR] 2.05, 95% confidence interval [CI] 1.25-3.37, p = 0.005, I2 = 0%) and die (OR 1.62, 95% CI 1.19-2.21, p = 0.002, I2 = 0%) compared with those who received bivalirudin. There were no differences in major bleeding events between heparin and bivalirudin recipients (OR 1.83, 95% CI 0.55-6.09, p = 0.33, I2 = 82.7%). In retrospective settings compared with heparin anticoagulation, bivalirudin was associated with less circuit-related thrombotic events and greater survival in adults supported on ECMO, without contributing to more bleeding complications. Prospective controlled studies comparing heparin and bivalirudin in adult ECMO patients are warranted to corroborate these findings.

Topics: Adult; Anticoagulants; Extracorporeal Membrane Oxygenation; Heparin; Hirudin Therapy; Hirudins; Humans; Peptide Fragments; Prospective Studies; Recombinant Proteins; Retrospective Studies; Thrombosis

The benefit:risk profile of bivalirudin versus heparin anticoagulation in patients with non-ST-segment-elevation myocardial infarction undergoing percutaneous coronary intervention (PCI) is uncertain. Study-level meta-analyses lack granularity to provide conclusive answers. We sought to compare the outcomes of bivalirudin and heparin in patients with non-ST-segment-elevation myocardial infarction undergoing PCI.. We performed an individual patient data meta-analysis of patients with non-ST-segment-elevation myocardial infarction in all 5 trials that randomized ≥1000 patients with any myocardial infarction undergoing PCI to bivalirudin versus heparin (MATRIX [Minimizing Adverse Hemorrhagic Events by Transradial Access Site and Systemic Implementation of Angiox], VALIDATE-SWEDEHEART [Bivalirudin Versus Heparin in ST-Segment and Non-ST-Segment Elevation Myocardial Infarction in Patients on Modern Antiplatelet Therapy in the Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies Registry Trial], ISAR-REACT 4 [Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment 4], ACUITY [Acute Catheterization and Urgent Intervention Triage Strategy], and BRIGHT [Bivalirudin in Acute Myocardial Infarction vs Heparin and GPI Plus Heparin Trial]). The primary effectiveness and safety end points were 30-day all-cause mortality and serious bleeding.. In patients with non-ST-segment-elevation myocardial infarction undergoing PCI, procedural anticoagulation with bivalirudin and heparin did not result in significantly different rates of mortality or ischemic events, including stent thrombosis and reinfarction. Bivalirudin reduced serious bleeding compared with heparin arising both from the access site and nonaccess sites.

Topics: Anticoagulants; Hemorrhage; Heparin; Hirudins; Humans; Myocardial Infarction; Non-ST Elevated Myocardial Infarction; Peptide Fragments; Percutaneous Coronary Intervention; Randomized Controlled Trials as Topic; Recombinant Proteins; Thrombosis; Treatment Outcome

The use of bivalirudin-based anticoagulation over heparin-based anticoagulation for coronary percutaneous intervention has been debated for a long time. Multiple trials have shown promising benefits of bivalirudin over heparin therapy with the most recent addition being the BRIGHT-4 trial. We performed a meta-analysis to assess evidence from these trials, focusing on the coronary intervention of the STEMI population.. This meta-analysis was performed based on PRISMA guidelines after registering in PROSPERO (CRD42023394701). Databases were searched for relevant articles published before January 2023. Pertinent data from the included studies were extracted and analyzed using RevMan v5.4.. Out of 2375 studies evaluated, 13 randomized control trials with 24 360 acute ST-elevation myocardial infarction patients were included for analysis. The bivalirudin-based anticoagulation reduced the net clinical events (OR 0.75, CI 0.61-0.92), major adverse cardiac or cerebral events (OR 0.85, CI 0.74-0.98), any bleeding (OR 0.61, CI 0.45-0.83), major bleeding (OR 0.54, CI 0.39-0.75), all-cause mortality (OR 0.79, CI 0.67-0.92) and cardiac mortality (OR 0.78, CI 0.65-0.93) significantly without increasing the risk of any stent thrombosis (OR 0.92, 95% CI 0.52-1.61), definite stent thrombosis (OR 1.17, 95% CI 0.62-2.22) and acute stent thrombosis (OR 2.06, 95% CI 0.69-6.09) significantly at 30 days.. Based on this meta-analysis, bivalirudin plus a post-PCI high-dose infusion-based anticoagulation during STEMI PCI has significant benefits over heparin therapy for cardiovascular outcomes without a significant increase in the risk of thrombotic outcomes.

Topics: Anticoagulants; Antithrombins; Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Randomized Controlled Trials as Topic; Recombinant Proteins; ST Elevation Myocardial Infarction; Thrombosis

Our study sought to investigate the efficacy and safety of bivalirudin versus those of unfractionated heparin (UFH) in patients undergoing extracorporeal membrane oxygenation (ECMO).. PubMed, EMBASE and Cochrane Library were searched for studies enrolling ECMO patients on bivalirudin and UFH (from inception till July 2021). Meta-analysis was conducted. The I. Fourteen eligible retrospective observational studies with 1501 subjects were identified. Compared with UFH, bivalirudin significantly reduced the risk of in-circuit thrombosis (OR = 0.44, 95% CI [0.31-0.61], p = 0.000), thrombosis (OR = 0.61, 95% CI [0.45-0.83], p= 0.002) and hospital mortality (OR = 0.78, 95% CI [0.61-0.99], p = 0.04) and had a positive impact on survival ECMO (OR = 1.50, 95% CI [1.04-2.16], p= 0.032). Decrease in risk of bleeding (OR = 0.36, 95% CI [0.14-0.91], p = 0.031) associated with bivalirudin was observed. Sources of heterogeneity were identified, and sensitivity analysis revealed similar results.. Our meta-analysis suggested that bivalirudin was associated with the decreased risk of in-circuit thrombosis, thrombosis, hospital mortality and bleeding in patients on ECMO and improved survival ECMO, indicating the superiority of bivalirudin to UFH in terms of efficacy and safety.

Topics: Adult; Anticoagulants; Child; Extracorporeal Membrane Oxygenation; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombosis; Treatment Outcome

Unfractionated heparin (UFH) has been the primary anticoagulant of choice on extracorporeal membrane oxygenation (ECMO). However, it is debatable whether bivalirudin (BIV), a direct thrombin inhibitor, may be considered a better alternative anticoagulant option.. We searched Embase, Pubmed, Cochrane library, Clinicaltrials.gov, CNKI and Wanfang databases up to 15 June 2021. Randomized controlled trials and observational studies were considered eligible for inclusion. Random-effects meta-analyses, including subgroup analyses, were conducted.. A total of 9 studies containing 994 patients were enrolled. All articles were retrospective cohort studies. Compared with UFH, BIV was associated with lower risks of major bleeding (risk ratio [RR]: 0.32, 95% confidence interval [CI] 0.22-0.49), ECMO in-circuit thrombosis (RR: 0.57, 95% CI 0.43-0.74), stroke (RR: 0.52, 95% CI 0.29-0.95) and in-hospital mortality (RR: 0.82, 95% CI 0.69-0.99), and higher rates of survival to ECMO decannulation (RR: 1.18, 95% CI 1.03-1.34). Pooled risk estimates did not show a significant association with clinical thrombotic events (RR: 0.69, 95% CI 0.45-1.07). Moreover, BIV was associated with a lower risk of ECMO in-circuit thrombosis and in-hospital mortality in the adult subgroup but not in the paediatric subgroup. However, leave-one-out sensitivity analyses indicated that the results of stroke, survival to ECMO decannulation and in-hospital mortality should be interpreted with caution.. BIV appears to be a potential alternative to UFH in paediatric and adult patients requiring ECMO.

Topics: Adult; Anticoagulants; Child; Extracorporeal Membrane Oxygenation; Heparin; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Stroke; Thrombosis

This meta-analysis is to evaluate the efficacy and safety of bivalirudin in patients with ST-elevation myocardial infarction (STEMI).. PubMed, Cochrane Library, Embase, CNKI, CBMdisc, and VIP database were searched. Randomized controlled trial (RCT) was selected and the meta-analysis was conducted by RevMan 5.1. The primary efficacy endpoint was the incidence of major adverse cardiovascular events (MACE) and the primary safety endpoint was the incidence of major bleeding. Secondary efficacy endpoints were myocardial infarction (MI), target vessel revascularization (TVR), stent thrombosis (ST), stock, mortality, and thrombocytopenia. The pooled risk ratios (RRs) with the corresponding 95% confidence intervals (CI) were used to assess the efficacy and safety of bivalirudin vs heparin.. Seven RCTs met the inclusion criteria, and 16,640 patients were included. We found that bivalirudin associated with lower risk of mortality (RR = 1.05; 95% CI = 0.74-1.49; P = .03; I = 2%), major bleeding (RR = 0.64; 95% CI = 0.54-0.75; P < .00001; I = 70%) and thrombocytopenia (RR = 0.39; 95% CI = 0.25-0.61; P < .0001; I = 0) compared with heparin. However, the use of bivalirudin increase the risk of MI(RR = 1.37; 95% CI = 1.10-1.71; P = .004; I = 25%) and ST(RR = 1.61; 95% CI = 1.05-2.47; P = .03; I = 70%) and has similar risk of MACE (RR = 1.00; 95% CI = 0.90-1.11; P = .97; I = 16%), TVR (RR = 1.43; 95% CI = 0.92-2.22; P = .11; I = 46%) and stock (RR = 1.43; 95% CI = 0.92-2.22; P = .11; I = 46%) compared with heparin used in STEMI patients.. Bivalirudin associated with lower risk of mortality, major bleeding and thrombocytopenia compared with heparin. However, the use of bivalirudin increase the risk of MI and ST and has similar risk of MACE, TVR and stock compared with heparin used in STEMI patients.

Topics: Antithrombins; Coronary Disease; Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Randomized Controlled Trials as Topic; Recombinant Proteins; Thrombosis; Treatment Outcome

Bivalirudin (Angiomax; The Medicines Company, Parsippany, NJ), a direct thrombin inhibitor, has found increasing utilization as a heparin alternative in the pediatric population, most commonly for the treatment of thrombosis secondary to heparin-induced thrombocytopenia. Due to the relative rarity of heparin-induced thrombocytopenia as well as the lack of Food and Drug Administration-approved indications in this age group, much of what is known regarding the pharmacokinetics and pharmacodynamics of bivalirudin in this population has been extrapolated from adult data. This narrative review will present recommendations regarding the use of bivalirudin for procedural anticoagulation in the pediatric population based on the published literature.

Topics: Adolescent; Age Factors; Antithrombins; Blood Coagulation; Cardiac Catheterization; Cardiac Surgical Procedures; Cardiopulmonary Bypass; Child; Child, Preschool; Drug Administration Schedule; Drug Dosage Calculations; Hemorrhage; Hirudins; Humans; Infant; Infant, Newborn; Models, Biological; Peptide Fragments; Perioperative Care; Recombinant Proteins; Risk Assessment; Risk Factors; Thrombosis; Treatment Outcome

Bivalirudin may be an effective alternative anticoagulant to heparin for use in percutaneous peripheral interventions. We aimed to compare the safety and efficacy of bivalirudin versus heparin as the procedural anticoagulant agent in patients undergoing percutaneous peripheral intervention.. For this meta-analysis and systematic review, we conducted a search in PubMed, Medline, Embase, and Cochrane for all the clinical studies in which bivalirudin was compared to heparin as the procedural anticoagulant in percutaneous peripheral interventions. Outcomes studied included all-cause mortality, all-bleeding, major and minor bleeding, and access site complications.. Eleven studies were included in the analysis, totaling 20,137 patients. There was a significant difference favoring bivalirudin over heparin for all-cause mortality (risk ratio 0.58, 95% CI 0.39-0.87), all-bleeding (risk ratio 0.62, 95% CI 0.50-0.78), major bleeding (risk ratio 0.61, 95% CI 0.39-0.96), minor bleeding (risk ratio 0.66, 95% CI 0.47-0.92), and access site complications (risk ratio 0.66, 95% CI 0.51-0.84). There was no significant difference in peri-procedural need for blood transfusions (risk ratio 0.79, 95% CI 0.57-1.08), myocardial infarction (risk ratio 0.87, 95% CI 0.59-1.28), stroke (risk ratio 0.77, 95% CI 0.59-1.01), intracranial bleeding (risk ratio 0.77, 95% CI 0.29-2.02), or amputations (OR 0.75, 95% CI 0.53-1.05).. Our meta-analysis suggests that bivalirudin use for percutaneous peripheral interventions is associated with lower all-cause mortality, bleeding, and access site complications as compared to heparin. Further large randomized trials are needed to confirm the current results.

Topics: Aged; Anticoagulants; Antithrombins; Catheterization, Peripheral; Endovascular Procedures; Female; Hemorrhage; Heparin; Hirudins; Humans; Male; Peptide Fragments; Peripheral Arterial Disease; Recombinant Proteins; Risk Assessment; Risk Factors; Thrombosis; Treatment Outcome

Patients with chronic kidney disease (CKD) have elevated bleeding and ischemic outcomes. We aim to assess the short- and long-term efficacy and safety of bivalirudin compared to heparin plus glycoprotein IIb/IIIa inhibitors (GPIs) in coronary artery disease (CAD) patients with CKD.. Randomized trials were searched in PubMed, Cochrane, and Embase databases up to January 2017. Among the trials retrieved, efficacy endpoints were defined as mortality, myocardial infarction (MI), repeat revascularization, stent thrombosis, and major adverse cardiac events (MACEs). Safety endpoints were reported as non-coronary artery bypass grafting (CABG) related major bleeding and thrombolysis in myocardial infarction (TIMI) major bleeding. Risk ratio (RR) and 95% confidence interval (CI) were calculated for each outcome using a fixed effect model.. Five studies with a total of 3796 patients were included. In short-term follow up (30 days), bivalirudin significantly reduced non-CABG related major bleeding (p=0.0004) and TIMI major bleeding (p=0.007) compared to heparin plus GPIs. No significant differences were observed in rates of mortality, MI, repeat revascularization, stent thrombosis, and MACEs between the two groups in short- and long-term follow up (6 months to 3 years). In patients with ST elevated myocardial infarction (STEMI) with concurrent CKD, the decreased non-CABG related major bleeding (p=0.04) without increasing ischemic events was also observed after short-term follow up.. (1) Bivalirudin is safer than and as effective as heparin plus GPIs in CAD patients with CKD. (2) Impaired renal function does not affect the safety benefits of bivalirudin. (3) Similar efficacy profiles were identified between the two groups after both short- and long-term follow up in the CAD patients with CKD.

Topics: Aged; Anticoagulants; Coronary Artery Disease; Female; Follow-Up Studies; Hemorrhage; Heparin; Hirudins; Humans; Kidney Function Tests; Male; Middle Aged; Myocardial Infarction; Patient Safety; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Randomized Controlled Trials as Topic; Recombinant Proteins; Renal Insufficiency, Chronic; Thrombosis; Treatment Outcome

Topics: Antithrombins; Arginine; Cardiac Surgical Procedures; Hirudins; Humans; Peptide Fragments; Perioperative Care; Pipecolic Acids; Recombinant Proteins; Sulfonamides; Thrombosis

The efficacy and safety of bivalirudin in patients undergoing percutaneous coronary intervention (PCI) for treatment of acute coronary syndromes (ACS) remains controversial despite recent evidence from large randomized-controlled trials (RCTs). Thus, this systematic review and meta-analysis sought to investigate the efficacy and safety of bivalirudin as compared to heparin in patients with ACS undergoing PCI.. Medline/PubMed, Cochrane Central Register of Controlled Trials, and Clinical Trials.gov databases were searched for RCTs. Primary endpoint was MACE consisting of all-cause death, myocardial infarction, and stroke within 30 days. Secondary endpoints were components of the primary endpoint and stent thrombosis. The primary safety endpoint was major bleeding. We identified 12 RCTs comprising 33,844 patients. Between bivalirudin and heparin, there were no significant differences for MACE (OR 1.06; 95% CI 0.96-1.17; p = 0.24), death, myocardial infarction, and stent thrombosis. Similar results were seen following stratification by use of glycoprotein inhibitors (GPI). Major bleeding trended to be less frequent in patients treated with bivalirudin. However, no safety benefit for bivalirudin was seen when use of GPI was balanced between groups (OR 0.88; 95% CI 0.67-1.16; p = 0.35; p for heterogeneity < 0.01).. Compared with heparin, bivalirudin was associated with a similar incidence of ischemic events following PCI for ACS. An association of bivalirudin with decreased bleeding was not seen with balanced use of GPI.

Topics: Acute Coronary Syndrome; Antithrombins; Global Health; Hirudins; Humans; Incidence; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; Thrombosis; Treatment Outcome

This paper mainly focuses on the evidence above and gives brief discussion to the recent literature on anticoagulation in fibrinolytic therapy and advances in antiplatelet therapy.. To date, no robust evidence is available challenging unfractionated heparin as the primary choice for anticoagulation in patients presenting with ST-segment elevation myocardial infarction. Further research should include efforts to refine anticoagulation strategies on an individual patient level. For patients undergoing primary percutaneous coronary intervention, bivalirudin could be used as an alternative to unfractionated heparin, while enoxaparin or fondaparinux is an alternative agent for patients treated with fibrinolytic therapy.

Topics: Anticoagulants; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; ST Elevation Myocardial Infarction; Thrombolytic Therapy; Thrombosis; Treatment Outcome

Available options for the treatment of advanced heart failure have expanded to include the use of mechanical circulatory assist devices to improve quality of life in those both eligible and ineligible for heart transplant. Although there have been significant advancements in device technologies, anticoagulation protocols, and multidisciplinary team management, bleeding and thrombosis are the most common adverse effects. Management strategies for pump thrombosis and their outcomes vary considerably among mechanical circulatory support centers and include intensification of antithrombotic therapy (medical) and device exchange (surgical). We describe a successful case of medical therapy for pump thrombosis with bivalirudin monotherapy.

Topics: Antithrombins; Extracorporeal Circulation; Heart Failure; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Thrombosis

Bivalirudin is an alternative to unfractionated heparin (UFH) anticoagulation during percutaneous coronary intervention. Previously, we have reported clinical benefit on major bleeding in favor of bivalirudin compared with UFH monotherapy but inconclusive results on mortality. Controversial data have been reported in the last 2 years. We conducted an updated meta-analysis including randomized trials and observational studies, which evaluated ischemic and bleeding outcomes for bivalirudin compared with UFH-only during percutaneous coronary intervention. We included 18 observational studies and 12 randomized trials published from 2003 to 2015. Primary outcomes were major adverse cardiovascular events within 30 days including death, myocardial infarction, and urgent revascularization and stent thrombosis, major bleeding, and transfusion. Overall, we found a significant risk reduction with bivalirudin for major bleeding (odds ratio [OR] 0.59, 95% confidence interval [CI] 0.49 to 0.71, p <0.0001) and for transfusion (OR 0.79, 95% CI 0.66 to 0.95, p = 0.01) and similar risk for major adverse cardiovascular events (OR 0.98, 95% CI 0.86 to 1.12, p = 0.80). However, there was a substantial increased risk of stent thrombosis associated with bivalirudin (OR 1.52, 95% CI 1.11 to 2.08, p = 0.009). No impact on mortality was found. Meta-regression analyses on major bleeding suggested that bivalirudin was more effective than UFH at doses >60 IU/kg and independent of radial access. In conclusion, compared with UFH monotherapy, bivalirudin remains associated with less bleeding risk but higher stent thrombosis risk. Further study remains required to define its role in current antithrombotic armamentarium.

Topics: Antithrombins; Fibrinolytic Agents; Global Health; Heparin; Hirudins; Humans; Incidence; Myocardial Ischemia; Peptide Fragments; Percutaneous Coronary Intervention; Postoperative Hemorrhage; Recombinant Proteins; Thrombosis

The optimal antithrombotic therapy in patients with ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention (PCI) remains a matter of debate. This updated meta-analysis investigated the impact of (1) bivalirudin (with and without prolonged infusion) and (2) prolonged PCI-dose (1.75 mg/hg per hour) bivalirudin infusion compared with conventional antithrombotic therapy on clinical outcomes in patients undergoing primary PCI.. Eligible randomized trials were searched through MEDLINE, EMBASE, Cochrane database, and proceedings of major congresses. Prespecified outcomes were major bleeding (thrombolysis in myocardial infarction major and Bleeding Academic Research Consortium 3-5), acute stent thrombosis, as well as all-cause and cardiac mortality at 30 days. Six randomized trials (n=17 294) were included. Bivalirudin compared with heparin (+/- glycoprotein-IIb/IIIa inhibitor) was associated with reduction in major bleeding (odds ratio [OR]: 0.65, 95% CI: 0.48-0.88, P=0.006, derived from all 6 trials), increase in acute stent thrombosis (OR: 2.75, 95% CI: 1.46-5.18, P=0.002, 5 trials), and lower rate of all-cause mortality (OR: 0.81, 95% CI: 0.67-0.98, P=0.03, 6 trials) as well as cardiac mortality (OR: 0.69, 95% CI: 0.55-0.87, P=0.001, 5 trials). The incidence of acute stent thrombosis did not differ between the prolonged PCI-dose bivalirudin and comparator group (OR: 0.81, 95% CI: 0.27-2.46, P=0.71, 3 trials), whereas the risk of bleeding was reduced despite treatment with high-dose bivalirudin infusion (OR: 0.28, 95% CI: 0.13-0.60, P=0.001, 3 trials).. Bivalirudin (with and without prolonged infusion) compared with conventional antithrombotic therapy in ST-segment-elevation myocardial infarction patients undergoing primary PCI reduces major bleeding and death, but increases the rate of acute stent thrombosis. However, prolonging the bivalirudin infusion at PCI-dose (1.75 mg/kg per hour) for 3 hours eliminates the excess risk of acute stent thrombosis, while maintaining the bleeding benefits.

Topics: Antithrombins; Hemorrhage; Hirudins; Humans; Infusions, Intravenous; Odds Ratio; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; ST Elevation Myocardial Infarction; Stents; Thrombosis

The use of extracorporeal membrane oxygenation (ECMO) support for cardiac and respiratory failure has increased in recent years. Improvements in ECMO oxygenator and pump technologies have aided this increase in utilization. Additionally, reports of successful outcomes in supporting patients with respiratory failure during the 2009 H1N1 pandemic and reports of ECMO during cardiopulmonary resuscitation have led to increased uptake of ECMO. Patients requiring ECMO are a heterogenous group of critically ill patients with cardiac and respiratory failure. Bleeding and thrombotic complications remain a leading cause of morbidity and mortality in patients on ECMO. In this review, we describe the mechanisms and management of hemostatic, thrombotic and hemolytic complications during ECMO support.

Topics: Anticoagulants; Blood Coagulation; Blood Coagulation Tests; Cardiac Output, Low; Cardiac Tamponade; Extracorporeal Membrane Oxygenation; Hemolysis; Hemorheology; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Purpura, Thrombocytopenic, Idiopathic; Recombinant Proteins; Respiratory Insufficiency; Thrombosis; von Willebrand Diseases

Although bivalirudin has been shown to reduce bleeding events in patients undergoing percutaneous coronary intervention, residual concerns remain about a possible higher risk of early (within 30 days) stent thrombosis (ST). Therefore, we performed a meta-analysis of randomised trials reporting ST events with bivalirudin compared to other antithrombotic therapies (heparins ± glycoprotein IIb/IIIa inhibitors). A systematic literature search of electronic resources was performed through May, 2014. The primary endpoint was definite early ST, according to Academic Research Consortium criteria. Secondary endpoints included: all-cause death, myocardial infarction and major bleeding. A total of 11 trials, including 16,415 patients, were accrued. Compared to other regimens, bivalirudin significantly increased the risk of early ST (odds ratio [OR]=1.80; 95 % confidence interval [CI], 1.28-2.52; p=0.0007) and reduced the risk of major bleeding (OR [95 %CI]=0.64 [0.51-0.82], p=0.0003), with a comparable risk of mortality or myocardial infarction. The higher risk of early ST was mainly attributable to acute (OR [95 % CI] =4.33 [2.33-8.05], p < 0.001) than subacute (OR [95 % CI] =0.89 [0.53-1.50], p =0.67) ST events (p for interaction < 0.001). Non-fatal myocardial infarction was the most common presentation (83 %) of early ST events, while death occurred infrequently (about 5 %). In conclusion, in patients undergoing PCI, bivalirudin compared to heparins is associated with a higher risk of early ST, which is mainly related to more frequent acute events. Further studies are required to evaluate alternative strategies to mitigate this risk, without hampering the benefits derived from the reduction in bleeding events with bivalirudin.

Topics: Acute Disease; Drug Therapy, Combination; Fibrinolytic Agents; Hemorrhage; Heparin; Hirudins; Humans; Multicenter Studies as Topic; Myocardial Infarction; Odds Ratio; Peptide Fragments; Percutaneous Coronary Intervention; Randomized Controlled Trials as Topic; Recombinant Proteins; Risk; Stents; Thrombosis; Treatment Outcome

Bivalirudin has gained ground against unfractionated heparin (UFH) in percutaneous coronary interventions (PCI), due to a reported better safety profile. However, whether bivalirudin may provide also advantages in clinical outcome beyond the known benefits in major bleedings, is still a debated matter and was, therefore, the aim of present meta-analysis of randomized trials, evaluating efficacy and safety of bivalirudin as compared with UFH in PCI.. Literature archives (Pubmed, EMBASE, Cochrane) and main scientific sessions were scanned. Primary endpoint was overall mortality. Secondary endpoints were: 1) mortality within 30-days; 2) overall and within 30-days non fatal myocardial infarction; 3) overall and within 30-days stent thrombosis. Safety endpoints were major bleedings (per protocol definition or TIMI classification). A prespecified analysis was conducted according to clinical presentation (Elective, ACS, STEMI).. A total of 22 randomized clinical were finally included, involving 40156 patients randomized to bivalirudin (52.9%) or to UFH (47.1%). Death occurred in 1100 (2.8%) of patients, with no difference between bivalirudin and UFH (2.7% vs 2.8% OR[95%C]=0.94[0.83,-.06], p=0.32, phet=0.48). The results did not change according to clinical presentation. By meta-regression analysis, the effects on mortality were not related to patients risk profile (r=-0.38(-0.89-0.14), p=0.15) or the reduction in bleeding complications (r=-0.008(-0.86-0.85), p=0.98). A significant increase in short-term stent thrombosis was observed with bivalirudin (OR[95%CI]=1.42 [1.10-1.83], p=0.006). However, Bivalirudin significantly reduced bleedings according to both study protocol definition (OR[95%CI]=0.62[0.56-0.69],p<0.00001; phet=0.0003) or TIMI major criteria (OR[95%CI]=0.65[0.53-0.79],p<0.0001, phet=0.95).. In present meta-analysis, among patients undergoing PCI, bivalirudin, as compared with UFH, is associated with a significant reduction in major bleeding complications that, however, does not translate into mortality benefits. Furthermore, bivalirudin is associated with higher rate of 30-days stent thrombosis and recurrent MI among STEMI patients.

Topics: Anticoagulants; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Randomized Controlled Trials as Topic; Recombinant Proteins; Thrombosis

Percutaneous coronary intervention with bivalirudin plus bail-out glycoprotein IIb/IIIa inhibitors has been shown to be as effective as unfractionated heparin plus routine glycoprotein IIb/IIIa inhibitors in preventing cardiac ischemic events, but with a lower bleeding risk. It is unknown whether bivalirudin would have the same beneficial effects if compared with heparin when the use of glycoprotein IIb/IIIa inhibitors was similar between treatment arms. We searched the MEDLINE, Web of Science, and Cochrane databases from inception until March 2015 for randomized trials that compared bivalirudin to heparin in patients undergoing percutaneous coronary intervention. We required that the intended use of glycoprotein IIb/IIIa inhibitors was similar between the study groups. Summary estimates were principally constructed by the Peto method. Fifteen trials met our inclusion criteria, which yielded 25,824 patients. Bivalirudin versus heparin was associated with an increased hazard of stent thrombosis (odds ratio [OR] 1.49, 95% confidence interval [CI] 1.15-1.92, P = .002, I2 = 16.9%), with a similar hazard of myocardial infarction (OR 1.09, 95% CI 0.98-1.22, P = .11, I2 = 35.8%), all-cause mortality (OR 0.88, 95% CI 0.72-1.08, P = .21, I2 = 31.5%) and major adverse cardiac events (OR 1.04, 95% CI 0.94-1.14, P = .46, I2 = 53.9%). Bivalirudin was associated with a reduced hazard of major bleeding (OR 0.80, 95% CI 0.70-0.92, P = .001, I2 = 63.5%). The dose of heparin in the control arm modified this association; when the dose of unfractionated heparin in the control arm was ≥ 100 units/kg, bivalirudin was associated with a reduction in major bleeding (OR 0.55, 95% CI 0.45-0.68, P < .0001), but when the dose of unfractionated heparin was ≤ 75 units/kg, bivalirudin was not associated with reduction in bleeding (OR 1.09, 95% CI 0.91-1.31, P = .36). Among patients undergoing PCI, bivalirudin was associated with an increased hazard of stent thrombosis. Bivalirudin may be associated with a reduced hazard of major bleeding; however, this benefit was no longer apparent when compared with a dose of unfractionated heparin ≤ 75 units/kg.

Topics: Acute Coronary Syndrome; Dose-Response Relationship, Drug; Follow-Up Studies; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Randomized Controlled Trials as Topic; Recombinant Proteins; Stents; Thrombosis; Treatment Outcome

Bivalirudin is commonly used for patients undergoing percutaneous coronary intervention (PCI), but there have been recent concerns that it may be associated with an increased risk of stent thrombosis and provide no benefit regarding major bleeding compared with active control.. We searched PubMed, clinicaltrials.gov, and conference proceedings for randomized controlled trials of bivalirudin versus active control in patients undergoing PCI. The main outcomes of interest were definite stent thrombosis, myocardial infarction, major bleeding, and mortality. We used random-effects modeling to pool the data. We included 25 trials involving 41,243 patients. Overall, use of bivalirudin compared with active control was associated with an increased risk of definite stent thrombosis (11 trials; 16,864 patients; RR, 1.73; 95% CI, 1.24-2.40; P<0.001; I(2)=0%), similar risk of acute myocardial infarction (22 trials; 40,578 patients; RR, 1.00; 95% CI, 0.87-1.16; P=0.96; I(2)=43%), decreased risk of major bleeding (25 trials; 41,243 patients; RR, 0.59; 95% CI, 0.49-0.72; P<0.001; I(2)=31%) and of cardiac death (6 trials; 6,956 patients; RR, 0.72; 95% CI, 0.53-0.99; P=0.05; I(2)=0%), but no change in all-cause mortality (24 trials; 41,058 patients; RR, 0.96; 95% CI, 0.81-1.15; P=0.69; I(2)=0%). Results were consistent across a wide set of subgroup and sensitivity analyses.. Compared with active control, bivalirudin is associated with increased risk of stent thrombosis but lower risk of major bleeding, with no discernible impact on all-cause mortality.

Topics: Antithrombins; Hemorrhage; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; Risk; Stents; Thrombosis

Thrombotic complications are increasing at a steady and significant rate in children, resulting in the more widespread use of anticoagulation in this population. Anticoagulant drugs in children can be divided into the older multitargeted agents (heparin, low-molecular-weight heparin, and warfarin) and the newer targeted agents (argatroban, bivalirudin, and fondaparinux). This review will compare and contrast the multitargeted and targeted anticoagulants and suggest situations in which it may be appropriate to use argatroban, bivalirudin, and fondaparinux. The various agents differ in their pharmacokinetics, requirements for therapeutic drug monitoring, frequency of administration, efficacy, and adverse effects. The targeted anticoagulants have properties that may make them more attractive for use in specific clinical situations. Prospective clinical trial data are presented supporting the current and future use of these agents in children.

Topics: Adolescent; Anticoagulants; Arginine; Child; Clinical Trials as Topic; Fondaparinux; Hematology; Heparin; Heparin, Low-Molecular-Weight; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Polysaccharides; Recombinant Proteins; Sulfonamides; Thrombin; Thrombosis; Treatment Outcome; Warfarin

Patients treated with bivalirudin in randomized clinical trials of percutaneous coronary intervention generally have less bleeding but more acute stent thrombosis (ST) than do patients treated with heparin, but differences have varied among trials.. We modeled the risk of major hemorrhage and ischemic outcomes 30 days after percutaneous coronary intervention by treatment assignment and the use of adjunctive therapies in 18 randomized clinical trials enrolling 41,871 patients. Overall bivalirudin caused less major bleeding (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.53-0.76), more ST (OR, 1.58; 95% CI, 1.19-2.09), and no difference in mortality (OR, 0.93; 95% CI, 0.77-1.14) than heparin. A risk-benefit analysis identified 19 fewer bleeds and 5 more STs for every 1000 patients treated with bivalirudin in place of heparin. No significant bleeding advantage of bivalirudin over heparin could be identified in randomized clinical trials when transradial access (OR, 0.89; 95% CI, 0.57-1.41) and planned glycoprotein IIb/IIIa inhibitors were used with bivalirudin in the majority of patients (OR, 1.07; 95% CI, 0.87-1.31). The use of prasugrel or ticagrelor eliminated bleeding differences (OR, 0.80; 95% CI, 0.63-1.03) but did not reduce the risk of ST after bivalirudin (OR, 2.20; 95% CI, 1.48-3.27).. Substituting bivalirudin for heparin conferred a tradeoff between bleeding and ST. Transradial access, adjunctive glycoprotein IIb/IIIa inhibitors, and potent P2Y12 inhibitors attenuated the bleeding advantage of bivalirudin over heparin but had no apparent effect on early ST. New approaches to reduce bleeding and ischemic complications during percutaneous coronary intervention warrant further investigation.

Topics: Clinical Trials as Topic; Hemorrhage; Heparin; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Glycoprotein GPIIb-IIIa Complex; Purinergic P2Y Receptor Antagonists; Recombinant Proteins; Stents; Thrombosis

To investigate the relative benefits of unfractionated heparin, low molecular weight heparin(LMWH), fondaparinux, and bivalirudin as treatment options for patients with ST segment elevation myocardial infarction undergoing percutaneous coronary intervention (PCI).. Mixed treatment comparison and direct comparison meta-analysis of randomized trials in the era of stents and P2Y12 inhibitors.. A search of Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL) for randomized trials comparing unfractionated heparin plus glycoprotein IIb/IIIa inhibitor(GpIIb/IIIa inhibitor), unfractionated heparin, bivalirudin, fondaparinux, or LMWH plus GpIIb/IIIa inhibitor for patients undergoing primary PCI.. The primary efficacy outcome was short term (in hospital or within 30 days) major adverse cardiovascular event; the primary safety outcome was short term major bleeding.. We identified 22 randomized trials that enrolled 22,434 patients. In the mixed treatment comparison models, when compared with unfractionated heparin plus GpIIb/IIIa inhibitor, unfractionated heparin was associated with a higher risk of major adverse cardiovascular events (relative risk 1.49 (95% confidence interval 1.21 to 1.84), as were bivalirudin (relative risk 1.34 (1.01 to 1.78)) and fondaparinux (1.78 (1.01 to 3.14)). LMWH plus GpIIb/IIIa inhibitor showed highest treatment efficacy, followed (in order) by unfractionated heparin plus GpIIb/IIIa inhibitor, bivalirudin, unfractionated heparin, and fondaparinux. Bivalirudin was associated with lower major bleeding risk compared with unfractionated heparin plus GpIIb/IIIa inhibitor (relative risk 0.47 (0.30 to 0.74)) or unfractionated heparin (0.58 (0.37 to 0.90)). Bivalirudin, followed by unfractionated heparin, LMWH plus GpIIb/IIIa inhibitor, unfractionated heparin plus GpIIb/IIIa inhibitor, and fondaparinux were the hierarchy for treatment safety. Results were similar in direct comparison meta-analyses: bivalirudin was associated with a 39%, 44%, and 65% higher risk of myocardial infarction, urgent revascularization, and stent thrombosis respectively when compared with unfractionated heparin with or without GpIIb/IIIa inhibitor. However, bivalirudin was associated with a 48% lower risk of major bleeding compared with unfractionated heparin plus GpIIb/IIIa inhibitor and 32% lower compared with unfractionated heparin alone.. In patients undergoing primary PCI, unfractionated heparin plus GpIIb/IIIa inhibitor and LMWH plus GpIIb/IIIa inhibitor were most efficacious, with the lowest rate of major adverse cardiovascular events, whereas bivalirudin was safest, with the lowest bleeding. These relationships should be considered in selecting anticoagulant therapies in patients undergoing primary PCI.

Topics: Anticoagulants; Antithrombins; Fondaparinux; Hemorrhage; Heparin; Heparin, Low-Molecular-Weight; Hirudins; Humans; Integrin beta3; Myocardial Infarction; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Glycoprotein GPIIb-IIIa Complex; Polysaccharides; Purinergic P2Y Receptor Antagonists; Recombinant Proteins; Stents; Thrombosis; Treatment Outcome

This article describes the pharmacology of approved parenteral anticoagulants. These include the indirect anticoagulants, unfractionated heparin (UFH), low-molecular-weight heparins (LMWHs), fondaparinux, and danaparoid, as well as the direct thrombin inhibitors hirudin, bivalirudin, and argatroban. UFH is a heterogeneous mixture of glycosaminoglycans that bind to antithrombin via a unique pentasaccharide sequence and catalyze the inactivation of thrombin, factor Xa, and other clotting enzymes. Heparin also binds to cells and plasma proteins other than antithrombin causing unpredictable pharmacokinetic and pharmacodynamic properties and triggering nonhemorrhagic side effects, such as heparin-induced thrombocytopenia (HIT) and osteoporosis. LMWHs have greater inhibitory activity against factor Xa than thrombin and exhibit less binding to cells and plasma proteins than heparin. Consequently, LMWH preparations have more predictable pharmacokinetic and pharmacodynamic properties, have a longer half-life than heparin, and are associated with a lower risk of nonhemorrhagic side effects. LMWHs can be administered once daily or bid by subcutaneous injection, without coagulation monitoring. Based on their greater convenience, LMWHs have replaced UFH for many clinical indications. Fondaparinux, a synthetic pentasaccharide, catalyzes the inhibition of factor Xa, but not thrombin, in an antithrombin-dependent fashion. Fondaparinux binds only to antithrombin. Therefore, fondaparinux-associated HIT or osteoporosis is unlikely to occur. Fondaparinux exhibits complete bioavailability when administered subcutaneously, has a longer half-life than LMWHs, and is given once daily by subcutaneous injection in fixed doses, without coagulation monitoring. Three additional parenteral direct thrombin inhibitors and danaparoid are approved as alternatives to heparin in patients with HIT.

Topics: Antithrombins; Arginine; Chondroitin Sulfates; Dermatan Sulfate; Dose-Response Relationship, Drug; Evidence-Based Medicine; Fibrinolytic Agents; Fondaparinux; Heparin; Heparin, Low-Molecular-Weight; Heparitin Sulfate; Hirudins; Humans; Infusions, Intravenous; Peptide Fragments; Pipecolic Acids; Polysaccharides; Practice Guidelines as Topic; Recombinant Proteins; Societies, Medical; Sulfonamides; Thrombin; Thrombosis; United States

Limitations and contraindications of heparins and oral vitamin K antagonists have led to the development of new anticoagulant drugs over the last few years. Argatroban is an intravenous direct thrombin inhibitor currently indicated for the prophylaxis and treatment of thrombosis associated with heparin-induced thrombocytopenia (HIT) and for patients at risk of HIT undergoing percutaneous coronary intervention (PCI). The role of argatroban for the treatment of acute coronary syndrome (ACS) is under evaluation.. This article reviews the potential use of argatroban for the treatment of ACS and presents the pharmacokinetic data currently available. The authors also present the pharmacodynamic literature of agratroban in addition to highlighting the safety and tolerability of the drug.. Theoretically, argatroban's pharmacokinetics makes it an attractive alternative to heparin. Pharmacological advantages of argatroban over heparin include a more-predictable anticoagulant response and the absence of a risk of HIT. Furthermore, argatroban has a fast and predictable dose-dependent anticoagulant effect with low inter-individual variability. It is non-immugenic, not susceptible to degradation by proteases and it is cleared via the liver. These characteristics confer argotroban a different profile from other anticoagulants. Agatroban is an effective alternative for patients when heparin, lepirudin and bivalirudin cannot be used. Its utility in ACS and PCI in non-HIT patients has been evaluated but further studies are warranted to define its role in this context.

Topics: Acute Coronary Syndrome; Animals; Antithrombins; Arginine; Disease Models, Animal; Drug Evaluation; Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Pipecolic Acids; Randomized Controlled Trials as Topic; Recombinant Proteins; Sulfonamides; Thrombocytopenia; Thrombosis

Anticoagulants are the cornerstone of therapy for conditions associated with arterial and venous thrombosis. Direct thrombin inhibitors (DTIs) are anticoagulants that bind to thrombin and block its enzymatic activity. The bivalent parenteral DTIs hirudin and bivalirudin were based on the observation that the salivary extracts of medicinal leeches prevented blood from clotting. Key events that facilitated the subsequent development of small molecule active site inhibitors, such as argatroban, were the observation that fibrinopeptide A had antithrombotic properties and determination of the crystal structure of thrombin. Hirudin and argatroban have found their niche for the treatment of patients with heparin-induced thrombocytopenia, whereas bivalirudin is approved as an alternative to heparin for patients undergoing percutaneous coronary intervention. The development of orally active direct thrombin inhibitors was challenging because of the need to convert water-soluble, poorly absorbable, active site inhibitors into fat-soluble prodrugs that were then transformed back to the active drug after intestinal absorption. Dabigatran etexilate was the first new oral anticoagulant to be approved for long-term anticoagulant treatment in 6 decades. This Review highlights the development of DTIs as a translational success story; an example in which the combination of scientific ingenuity, structure-based design, and rigorous clinical trials has created a new class of anticoagulants that has improved patient care.

Topics: Anticoagulants; Antithrombins; Arginine; Hirudin Therapy; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Recombinant Proteins; Sulfonamides; Thrombosis; Translational Research, Biomedical

Antithrombotic therapy plays an integral role in percutaneous coronary intervention (PCI). Bivalirudin has been evaluated in elective procedures and across the spectrum of acute coronary syndromes and is associated with decreased bleeding events compared to unfractionated heparin (UFH) in combination with glycoprotein IIb/IIIa inhibitors (GPI) when used for the duration of PCI. The use of bivalirudin beyond the end of PCI is not as well established but is being explored as an option for specific patients.. A small increase in stent thrombosis and ischemic events has been identified in large clinical trials using bivalirudin for acute coronary syndromes (ACS). The reasons for this finding are unclear, but may be related to the short duration of bivalirudin or the timing and dose of antiplatelet therapies in the trials. Two small, single center trials have evaluated bivalirudin continued for 4 h beyond the end of PCI. These trials suggest that prolonged bivalirudin infusions result in less periprocedural myocardial infarction with no increase in bleeding compared to intraprocedural only bivalirudin. However, these studies were not powered to identify a difference in bleeding. Efforts to decrease periprocedural myocardial infarction should include the appropriate use of oral antiplatelet agents. An adequate and appropriately timed loading dose of thienopyridines plays a key role in decreasing complications of PCI.. The strategy of prolonging the bivalirudin infusion at a reduced infusion rate for 4 h after completion of the PCI procedure was explored and offers promising results.

Topics: Acute Coronary Syndrome; Angioplasty, Balloon, Coronary; Antithrombins; Dose-Response Relationship, Drug; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Stents; Thrombosis; Time Factors

Topics: Anticoagulants; Arginine; Autoantibodies; Chondroitin Sulfates; Dermatan Sulfate; Drug Monitoring; Fondaparinux; Heparin; Heparitin Sulfate; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Platelet Count; Platelet Factor 4; Polysaccharides; Recombinant Proteins; Sulfonamides; Thrombocytopenia; Thrombosis; Warfarin

Thrombocytopenia following heparin administration can be associated with an immune reaction, now referred to as heparin-induced thrombocytopenia (HIT). HIT is essentially a prothrombotic disorder mediated by an IgG antiplatelet factor 4/heparin antibody, which induces platelet, endothelial cell, monocyte, and other cellular activation, leading to thrombin generation and thrombotic complications. Indeed, HIT can also be regarded as a serious adverse drug effect. Importantly, HIT can be a life-threatening and limb-threatening condition frequently associated with characteristically severe and extensive thromboembolism (both venous and arterial) rather than with bleeding. This article provides an overview of HIT, with an emphasis on the clinical diagnosis and management.

Topics: Anticoagulants; Arginine; Chondroitin Sulfates; Dermatan Sulfate; Female; Heparin; Heparitin Sulfate; Hirudins; Humans; Male; Monitoring, Physiologic; Peptide Fragments; Pipecolic Acids; Platelet Aggregation Inhibitors; Platelet Count; Prognosis; Randomized Controlled Trials as Topic; Recombinant Proteins; Risk Factors; Safety Management; Severity of Illness Index; Sulfonamides; Survival Rate; Thrombocytopenia; Thrombosis; Time Factors

Diabetic patients with acute coronary syndromes (ACSs) are at a high risk for subsequent cardiovascular events but derive, at the same time, greater benefit from evidence-based therapy than non-diabetic individuals. State-of-the-art anti-thrombotic therapy includes a triple anti-platelet combination - aspirin, clopidogrel and glycoprotein (GP) IIb/IIIa receptor inhibitors - and unfractionated heparin or enoxaparin. For low- or medium-risk individuals, a treatment based on aspirin, clopidogrel and bivalirudin is a valuable alternative. Prasugrel, a new and more potent inhibitor of the platelet P2Y(12) receptor, has to be regarded as the most promising anti-thrombotic agent for diabetic patients with ACS. This agent may replace clopidogrel - and possibly GP IIb/IIIa inhibitors - in the future. In addition to aggressive anti-thrombotic therapy, diabetic patients should undergo systematic early invasive angiography if presenting with non-ST-segment elevation ACS, and immediate percutaneous coronary intervention if presenting with ST-segment elevation myocardial infarction. Indeed, the benefit derived from these strategies appears to be more pronounced in the diabetic population than in non-diabetic individuals. Despite the benefit, multiple surveys have demonstrated that, in the setting of ACS, diabetic patients receive evidence-based therapy less frequently than non-diabetic counterparts.

Topics: Acute Coronary Syndrome; Anticoagulants; Aspirin; Blood Glucose; Clopidogrel; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Enoxaparin; Hirudins; Humans; Hypoglycemic Agents; Peptide Fragments; Piperazines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Prasugrel Hydrochloride; Randomized Controlled Trials as Topic; Recombinant Proteins; Thiophenes; Thrombosis; Ticlopidine

Patients who present with acute coronary syndromes, particularly ST-segment elevation myocardial infarction (STEMI), have abnormalities in platelet size and function that predispose to thrombotic events. Both preprocedural platelet reactivity and mean platelet volume are directly correlated with the occurrence of adverse ischemic events and impaired microvascular reperfusion following primary percutaneous coronary intervention (PCI) for STEMI. The Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial demonstrated a similar ischemic event rate to 30 days with a significantly lower bleeding event rate (enhanced net clinical benefit) in favor of bivalirudin monotherapy (with provisional platelet glycoprotein [GP] IIb/IIIa receptor blockade) in comparison with unfractionated heparin plus GP IIb/IIIa blockade in patients undergoing primary PCI for STEMI. The bivalirudin monotherapy was associated with a highly significant greater incidence of acute stent thrombosis. This observation provides the opportunity for strategies that enhance periprocedural platelet inhibition to reduce stent thrombosis and to potentially improve the safety and efficacy of periprocedural adjunctive pharmacotherapy above that achieved by bivalirudin monotherapy alone.

Topics: Angioplasty, Balloon, Coronary; Anticoagulants; Chemotherapy, Adjuvant; Clopidogrel; Drug Therapy, Combination; Hemorrhage; Heparin; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Piperazines; Platelet Activation; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Prasugrel Hydrochloride; Randomized Controlled Trials as Topic; Recombinant Proteins; Risk Assessment; Thiophenes; Thrombosis; Ticlopidine; Time Factors; Treatment Outcome

With the availability of new data and the recent release of new European and US guidelines, contemporary care paradigms for the treatment of patients with non-ST-elevation acute coronary syndromes (NSTE ACS), including those undergoing percutaneous coronary intervention, are likely to undergo substantial changes. In recognition of this shifting landscape as well as the impact of new guidelines on care models for the treatment of patients with NSTE ACS, a roundtable was convened on October 25, 2007, to discuss the implications of these changes. The purpose of this review is to summarize the presentations and subsequent discussions from the roundtable, which examined the guidelines and evidence from a variety of perspectives, and to explore the best ways to incorporate new treatment paradigms into everyday clinical care. The multiple viewpoints expressed by the roundtable attendees illustrate the recognition that at this point, consensus has not been reached on the optimum algorithm for treatment of these patients. This article focuses on issues discussed during the roundtable from the perspective of the practicing cardiologist.

Topics: Acute Coronary Syndrome; Algorithms; Angioplasty, Balloon, Coronary; Anticoagulants; Aspirin; Cardiovascular Agents; Clinical Trials as Topic; Clopidogrel; Emergency Treatment; Evidence-Based Medicine; Fibrinolytic Agents; Hirudins; Humans; Peptide Fragments; Piperazines; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Postoperative Hemorrhage; Practice Guidelines as Topic; Prasugrel Hydrochloride; Recombinant Proteins; Risk Assessment; Stents; Thiophenes; Thrombosis; Ticlopidine

The options for drug-controlled anticoagulation are becoming noticeably more manifold. In the area of anaesthesiology and intensive care, there are furthermore special disease patterns, such as heparin-induced thrombocytopenia (HIT) to be known, diagnosed and treated. This article gives a review of the substance groups of the direct thrombin inhibitors (DTI) as alternative anticoagulants for HIT in combination with cardiovascular diseases. For the administration of DTIs, experience and the correct dose are the keys to success and are the deciding factors for the two sides of haemostasis: thrombosis and haemorrhage.

Topics: Anesthesia; Anticoagulants; Cardiovascular Surgical Procedures; Critical Care; Hemorrhage; Hemostasis; Heparin; Heparin Antagonists; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Thrombin; Thrombosis

Bivalirudin is a direct thrombin inhibitor (DTI) frequently used for anticoagulation in the setting of invasive cardiology, particularly percutaneous coronary intervention (PCI). Bivalirudin has a unique pharmacologic profile: unlike other marketed DTIs, it undergoes predominant non-organ elimination (proteolysis), and has the shortest half-life (approximately 25 min). Its affinity for thrombin is intermediate between that of lepirudin (highest) and argatroban (lowest)--this helps explain why it interferes with functional clotting assays to an extent intermediate between that achieved by these two other DTIs. This effect is best known for the PT (INR)--higher affinity for thrombin corresponds to lower molar DTI requirements to prolong the APTT; in turn, lower concentrations required for APTT prolongation (and, presumably, in-vivo effect) result in reduced PT (INR) prolongation. Bivalirudin is primarily used for its first FDA-approved indication, namely anticoagulation during percutaneous transluminal coronary angioplasty ("balloon angioplasty"), the most frequent type of PCI. Bivalirudin is also indicated for PCI with provisional use of glycoprotein IIb/IIIa antagonist therapy, and for patients with, or at risk of, heparin-induced thrombocytopenia (HIT), or HIT with thrombosis syndrome (HITTS), undergoing PCI. The bivalirudin development program has used a "quadruple" endpoint comprising a "triple" efficacy endpoint plus major bleeding - this approach anticipated the subsequent emphasis on strategies to improve clinical outcomes through bleeding reduction. Besides summarizing the key trials evaluating bivalirudin use for acute coronary syndrome (especially employing PCI), we review also the studies of bivalirudin as anticoagulant for "on-" and "off-pump" cardiac surgery, including both HIT and non-HIT situations.

Topics: Acute Coronary Syndrome; Amino Acid Sequence; Angioplasty, Balloon, Coronary; Animals; Anticoagulants; Blood Coagulation; Cardiac Surgical Procedures; Fibrinolytic Agents; Hemorrhage; Hemostasis, Surgical; Heparin; Hirudins; Humans; Molecular Sequence Data; Peptide Fragments; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Thrombocytopenia; Thrombosis

Patients with or at risk of heparin-induced thrombocytopenia (HIT) who are undergoing percutaneous coronary intervention (PCI) are at particular risk of thrombosis due to the prothrombotic nature of HIT and the endovascular disruption from PCI. Patients require aggressive anticoagulation during PCI, and alternative, nonheparin anticoagulation is recommended over heparin in patients with acute or previous HIT. Argatroban, bivalirudin, and lepirudin are nonheparin, fast-acting, parenteral direct thrombin inhibitors (DTIs). Multicenter, prospective studies have demonstrated that argatroban and lepirudin each reduce thrombosis in HIT and that argatroban and bivalirudin each provide adequate anticoagulation during PCI in patients with or at risk of HIT. We review current therapeutic practices with direct thrombin inhibitors in patients with or at risk of HIT during PCI, including individuals requiring periprocedural anticoagulation, and the factors influencing the choice of DTI in this setting.

Topics: Angioplasty, Balloon, Coronary; Antithrombins; Arginine; Drug Interactions; Economics, Pharmaceutical; Fibrinolytic Agents; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Platelet Aggregation Inhibitors; Recombinant Proteins; Sulfonamides; Thrombocytopenia; Thrombosis

Heparin-induced thrombocytopenia (HIT) is an immune-mediated adverse effect that typically manifests several days after the start of heparin therapy, although both rapid- and delayed-onset HIT have been described. Its most serious complication is thrombosis. Although not all patients develop thrombosis, it can be life threatening. The risk of developing HIT is related to many factors, including the type of heparin product administered, route of administration, duration of therapy, patient population, and previous exposure to heparin. The diagnosis of HIT is typically based on clinical presentation, exposure to heparin, and presence of thrombocytopenia with or without thrombosis. Antigen and activation laboratory assays are available to support the diagnosis of HIT. However, because of the limited sensitivity and specificity of these assays, bedside probability scales for HIT were developed. When HIT is suspected, prompt cessation of all heparin therapy is necessary, along with initiation of alternative anticoagulant therapy. Two direct thrombin inhibitors--argatroban and lepirudin--are approved for the management of HIT in the United States, and bivalirudin is approved for use in patients with HIT who are undergoing percutaneous coronary intervention. Other agents, although not approved to manage HIT, have also been used; however, their role in therapy requires further evaluation. A comprehensive HIT management strategy involves the evaluation of numerous factors. Many patients, including those undergoing coronary artery bypass surgery, those with acute coronary syndromes, those with hepatic or renal insufficiency, and children, require special attention. Clinicians must become familiar with the available information on this serious adverse effect and its treatment so that optimum patient management strategies may be formulated.

Topics: Anticoagulants; Antithrombins; Arginine; Heparin; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Recombinant Proteins; Sulfonamides; Thrombocytopenia; Thrombosis

Topics: Angina, Unstable; Anticoagulants; Azetidines; Benzimidazoles; Benzylamines; Brain Ischemia; Clinical Trials as Topic; Coumarins; Dabigatran; Factor Xa Inhibitors; Fibrinolytic Agents; Fondaparinux; Forecasting; Hemorrhage; Heparin; Heparin, Low-Molecular-Weight; Hirudins; Humans; Morpholines; Myocardial Infarction; Peptide Fragments; Polysaccharides; Prothrombin; Pyrazoles; Pyridines; Pyridones; Recombinant Proteins; Rivaroxaban; Thiophenes; Thrombin; Thrombophilia; Thrombosis; Warfarin

The anticoagulant properties of heparin were discovered in 1916, and by the 1930s researchers were evaluating its therapeutic use in clinical trials. Treatment of unstable angina with unfractionated heparin (UFH), in addition to aspirin, was introduced into clinical practice in the early 1980s. UFH was combined with aspirin to suppress thrombin propagation and fibrin formation in patients presenting with acute coronary syndromes (ACS) or patients undergoing percutaneous coronary intervention (PCI). However, UFH stimulates platelets, leading to both activation and aggregation, which may further promote clot formation. Clinical trials have demonstrated that newer agents, such as the low-molecular-weight heparins (LMWHs), are superior to UFH for medical management of unstable angina or non-ST-segment elevation myocardial infarction. Increasingly, the LMWHs have been used as the anticoagulant of choice for patients presenting with ACS. For patients undergoing PCI, LMWH provides no sub-stantial benefit over UFH for anticoagulation; however, direct thrombin inhibitors (DTIs) have demonstrated safety and efficacy in this setting. UFH is likely to be replaced by more effective and safer antithrombin agents, such as DTIs. DTIs have antiplatelet effects, anticoagulant action, and most do not bind to plasma proteins, thereby providing a more consistent dose-response effect than UFH. The FDA has approved 4 parenteral DTIs for various indications: lepirudin, argatroban, bivalirudin, and desirudin. The antiplatelet, anticoagulant, and pharmacokinetic properties of bivalirudin support its use as the anticoagulant of choice for both lower- and higher-risk patients, including those undergoing PCI.

Topics: Acute Disease; Angina Pectoris; Angina, Unstable; Angioplasty, Balloon, Coronary; Anticoagulants; Arginine; Fondaparinux; Hemorrhage; Heparin; Heparin, Low-Molecular-Weight; Hirudins; Humans; Models, Molecular; Molecular Structure; Myocardial Ischemia; Peptide Fragments; Pipecolic Acids; Platelet Activation; Polysaccharides; Recombinant Proteins; Sulfonamides; Syndrome; Thrombin; Thrombosis

The accumulation of evidence of efficacy and tolerance led to the FDA approval of bivalirudine in the United States and it has progressively replaced the use of unfractionated heparin in its traditional indication in the catheter laboratory of the Washington Hospital Center. This change has probably contributed to the reduction of bleeding complications observed in this institution. The experience acquired also showed a reduced risk of enzyme rises after the procedure. The use of bivalirudine in conditions comparable to those of the REPLACE II trial confirms that anti GPIIb/IIIa molecules should be reserved for extreme circumstances rather than be systematically associated with heparin, so significantly reducing the cost of the interventional procedures.

Topics: Angioplasty, Balloon, Coronary; Antithrombins; Fibrinolytic Agents; Hirudins; Humans; Peptide Fragments; Postoperative Hemorrhage; Recombinant Proteins; Stents; Thrombosis; Troponin I

Topics: Anticoagulants; Arginine; Cardiac Surgical Procedures; Cardiovascular Diseases; Chondroitin Sulfates; Dermatan Sulfate; Diagnosis, Differential; Fondaparinux; Heparin; Heparitin Sulfate; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Platelet Aggregation Inhibitors; Platelet Factor 4; Polysaccharides; Recombinant Proteins; Sensitivity and Specificity; Sulfonamides; Thrombocytopenia; Thrombosis

Clinical coagulation laboratory tests do not accurately reflect hemostasis and thrombosis in vivo. Thrombin generation in vivo occurs in 3 overlapping phases: initiation, priming, and propagation. During initiation, injury to the vessel wall exposes the cells to tissue factors, which lead to the production of small amounts of thrombin. During priming, the thrombin that is generated initially binds to platelets and activates them through protease-activated receptors. During the propagation phase, factor X is activated by the factor IXa/VIIIa complex that is assembled on the activated platelet surface. Subsequent formation of factor Xa/Va complexes on the platelet surface leads to a burst of thrombin and fibrin formation. Pharmacologic concentrations of a direct thrombin inhibitor, bivalirudin, inhibit thrombin-induced activation of platelets to a greater extent than pharmacologic concentrations of unfractionated heparin.

Topics: Anticoagulants; Blood Platelets; Fibrin; Heparin; Hirudins; Humans; Male; Peptide Fragments; Platelet Activation; Recombinant Proteins; Thrombin; Thromboplastin; Thrombosis

More than 1.2 million percutaneous coronary intervention (PCI) procedures are performed each year in the United States, with average hospital costs of more than $10,000 per procedure. Despite ongoing improvements in device technology and adjunct pharmacology, both ischemic complications (eg, periprocedural myocardial infarction) and bleeding complications remain relatively common and are associated with both increased costs (in the short term) and mortality (in the longer term). Recently, the Randomized Evaluation of PCI Linking Angiomax to Reduced Clinical Events (REPLACE)-2 clinical trial demonstrated that the use of the direct thrombin inhibitor, bivalirudin, with provisional glycoprotein (GP) IIb/IIIa inhibitor for selected patients in place of a conventional anticoagulation strategy of heparin and routine use of a GP IIb/IIIa inhibitor, resulted in comparable rates of ischemic complications and a significant reduction in the frequency of both major and minor bleeding complications. A prospectively designed economic analysis was performed using data from 4651 US patients who participated in REPLACE-2. In this analysis, patients who were assigned to the bivalirudin and provisional GP IIb/IIIa inhibitor strategy had anticoagulation costs during PCI that were approximately $400 per patient lower than those with heparin plus routine GP IIb/IIIa inhibition. Bivalirudin also produced corresponding decreases in total in-hospital costs and aggregate 30-day medical care costs. These cost savings derived both from the lower acquisition cost of the antithrombotic therapy and the reduced rate of bleeding complications, which accounted for approximately 20% of the cost offsets. These results suggest that for patients similar to those studied in REPLACE-2 (ie, low to moderate risk PCI procedures), use of bivalirudin and provisional GP IIb/IIIa inhibition compared with heparin and routine GP IIb/IIIa inhibition can result in similar rates of ischemic complications, reduced bleeding, and substantial cost savings to both hospitals and the healthcare system. Whether these benefits can be extended to higher risk patient subsets including patients with non-ST elevation or ST elevation myocardial infarction is currently under investigation.

Topics: Angioplasty, Balloon, Coronary; Anticoagulants; Antithrombins; Cardiac Catheterization; Drug Costs; Hirudins; Humans; Laboratories, Hospital; Myocardial Ischemia; Peptide Fragments; Recombinant Proteins; Thrombosis

The standard of care for patients with acute coronary syndrome is antithrombotic and antiplatelet therapies along with early percutaneous coronary intervention. Because of the limitations of heparin, there has been an interest in direct thrombin inhibitors, such as bivalirudin, which is now the anticoagulant of choice in percutaneous coronary intervention.

Topics: Acute Disease; Angioplasty, Balloon, Coronary; Anticoagulants; Coronary Disease; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Thrombosis

Bivalirudin is a member of the direct thrombin inhibitor group of anticoagulants. It has been evaluated as an alternative to unfractionated and low-molecular-weight heparins in the settings of percutaneous coronary intervention (PCI) and acute coronary syndrome (ACS). Results of clinical trials to date suggest bivalirudin is a viable alternative to the use of a heparin combined with a glycoprotein (GP) IIb/IIIa inhibitor in these settings. Thrombin has a central role in coagulation and platelet activation in ACS and during PCI. Its direct inhibition is an attractive target for therapy in these settings. Bivalirudin is a 20 amino acid polypeptide hirudin analog. It displays bivalent and reversible binding to the thrombin molecule, inhibiting its action. Direct inhibition of thrombin with bivalirudin has theoretical pharmacokinetic and pharmacodynamic advantages over the indirect anticoagulants. A reduction in rates of bleeding without loss of anti-thrombotic efficacy has been a consistent finding across multiple clinical trials. There may be economic benefits to the use ofbivalirudin if it permits a lower rate of use of the GP IIb/IIIa inhibitors. This article reviews the pharmacology of bivalirudin and clinical trial evidence to date. There are now data from multiple clinical trials and meta-analyses in the setting of ACS and PCI. Early results from the acute catheterization and urgent intervention strategy (ACUITY) trial are discussed.

Topics: Acute Disease; Angioplasty, Balloon, Coronary; Anticoagulants; Hemorrhage; Heparin; Hirudins; Humans; Myocardial Ischemia; Peptide Fragments; Platelet Aggregation Inhibitors; Recombinant Proteins; Secondary Prevention; Syndrome; Thrombin; Thrombosis

Topics: Anticoagulants; Arginine; Azetidines; Benzylamines; Blood Coagulation; Fondaparinux; Heparin; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Polysaccharides; Recombinant Proteins; Sulfonamides; Thrombin; Thrombosis; Warfarin

Topics: Acute Disease; Angioplasty, Balloon, Coronary; Anticoagulants; Arginine; Atrial Fibrillation; Azetidines; Benzylamines; Clinical Trials as Topic; Coronary Disease; Heparin; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Pipecolic Acids; Recombinant Proteins; Sulfonamides; Syndrome; Thrombin; Thromboembolism; Thrombosis; Venous Thrombosis

Classic anticoagulant drugs are very effective, save lives and have been used for more than 50 years. Nevertheless, some drawbacks are encountered in their routine clinical use. Recently, pharmaceutical research has developed new drugs, some of which are already on the market. This is the case of fondaparinux, a pentasaccharide which can interact with antithrombin, thus inhibiting factor Xa. Modification of its structure (idraparinux) has led to more stable binding with antithrombin and to an increase in its half-life allowing for once-a-week administration. Another important oral compound is ximelagatran which directly binds thrombin and blocks its catalytic site. There is no need for laboratory control, and phase II and phase III studies are encouraging. Thus, in the next few years, we may witness great changes in the treatment of patients with thromboembolic disorders.

Topics: Anticoagulants; Arginine; Azetidines; Benzylamines; Drug Design; Fibrinolytic Agents; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Platelet Aggregation Inhibitors; Prodrugs; Recombinant Proteins; Sulfonamides; Thrombosis

Coronary artery thrombosis is usually triggered by platelet-rich thrombus superimposed on a spontaneously or mechanically disrupted atherosclerotic plaque. Thrombin and platelets both play a role in this process. Unfractionated heparin and aspirin have served as cornerstones in the prevention and treatment of intracoronary thrombus, but unfractionated heparin has several limitations that necessitate the use of adjunctive therapies, such as glycoprotein IIb/IIIa receptor inhibitors and clopidogrel, in order to reduce the risk of ischemic events. These combination therapies, however, typically increase the risk for bleeding complications, as well as the cost and complexity of treatment. Bivalirudin (Angiomax, The Medicines Company), a thrombin-specific anticoagulant, does not share heparin's limitations. Bivalirudin appears to provide clinical advantages over unfractionated heparin therapy in acute coronary syndrome patients and those undergoing percutaneous coronary intervention, without increasing cost or complexity of treatment for most patients.

Topics: Acute Disease; Angioplasty, Balloon, Coronary; Anticoagulants; Clinical Trials as Topic; Coronary Disease; Heparin; Hirudins; Humans; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Randomized Controlled Trials as Topic; Recombinant Proteins; Syndrome; Thrombosis

Ximelagatran and bivalirudin are direct thrombin inhibitors that have been studied for the prevention and treatment of thrombosis and have potential advantages over the traditional indirect thrombin inhibitors (i.e., warfarin, unfractionated heparin and low molecular-weight heparin). They are both reversible inhibitors of thrombin and block both circulating and fibrin-bound thrombin. Ximelagatran and bivalirudin possess favourable pharmacokinetic and pharmacodynamic profiles including wider therapeutic indices, faster onsets of action and less interpatient variability compared to indirect thrombin inhibitors. Ximelagatran has shown favourable clinical trial results in venous thromboembolism prophylaxis and atrial fibrillation. Similarly, bivalirudin has shown positive results in patients with acute coronary syndromes, however, further investigation is needed. Ximelagatran and bivalirudin have shown promising results in the management of thrombosis and the results of future studies confirming their use for the aforementioned indications are anticipated.

Topics: Acute Disease; Administration, Oral; Antithrombins; Azetidines; Benzylamines; Clinical Trials, Phase III as Topic; Coronary Disease; Double-Blind Method; Hirudins; Humans; Peptide Fragments; Randomized Controlled Trials as Topic; Recombinant Proteins; Syndrome; Thrombosis

Topics: Angiography; Angioplasty, Balloon; Antithrombins; Heparin, Low-Molecular-Weight; Hirudins; Humans; Peptide Fragments; Peripheral Vascular Diseases; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Thrombosis

Our current understanding of hemostasis and the roles of coagulation and platelets has evolved in recent years from the old "coagulation cascade" and "platelet pathway" models to an inter-related, cell-based model that more accurately represents in-vivo processes and better reflects clinical observations. The new model makes it apparent that thrombin is a key effector and modulator of hemostasis, and that activation of coagulation and platelets cannot be viewed as separate processes. Thrombin is a potent platelet agonist, and recent data indicate that thrombin may be the most critical activator of tissue-factor-induced thrombosis. Minute quantities of thrombin generated at the site of plaque disruption or arterial injury activates platelets and amplifies its own production, resulting in an explosive burst of thrombin production after clot formation. Thrombin-induced activation of platelets and other cells may contribute to inflammatory processes that are increasingly recognized as playing an important role in acute coronary syndromes (ACS) and coronary interventions. Along with a clearer understanding of the biology of thrombosis and hemostasis, better methods for studying the mechanisms of coagulation and platelet activation and the interaction of these processes in vivo have provided a new understanding of the method by which antithrombotic agents work. The physiological basis of thrombosis and hemostasis has important implications for treatment strategies in ACS, and for outcomes of percutaneous coronary interventions (PCI). With this increased understanding, the limitations of heparin and the advantages of the direct thrombin inhibitor bivalirudin (Angiomax, The Medicines Company) become apparent--providing a mechanistic rationale for the clinical benefit recently demonstrated in the Randomized Evaluation of PCI Linking Angiomax to Reduced Clinical Events (REPLACE-2) PCI trial.

Topics: Animals; Antithrombins; Blood Coagulation; Blood Coagulation Factors; Blood Platelets; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Thrombin; Thrombosis

The chemistry and pharmacology, pharmacokinetics, pharmacodynamics, adverse effects, drug interactions, dosing and administration, and pharmacoeconomics of bivalirudin are reviewed; clinical trials of bivalirudin's application in percutaneous coronary intervention (PCI) are also discussed. Bivalirudin is a direct thrombin inhibitor approved for use in PCI. It reversibly binds to thrombin's catalytic site and substrate recognition site and blocks both circulating and fibrin-bound thrombin. Peak concentrations occur in less than 5 minutes after bolus-dose administration, and its half-life is approximately 25 minutes. It is primarily eliminated renally, and dosage reduction may be required in patients with severe renal dysfunction. Two clinical trials have demonstrated that bivalirudin is at least as effective as unfractionated heparin (UFH) in preventing ischemic complications in PCI. Other trials have shown that bivalirudin has beneficial ischemic and hemorrhagic outcomes in a more modern PCI setting (i.e., intracoronary stent placement, clopidogrel, and glycoprotein IIb/IIIa-receptor inhibitors). Bivalirudin combined with provisional glycoprotein IIb/IIIa inhibitors was noninferior to UFH with planned glycoprotein IIb/IIIa inhibitors and superior to UFH alone with respect to ischemic and hemorrhagic endopoints in PCI. Major bleeding with bivalirudin has occurred in approximately 3% of patients in clinical trials, and it is not known to have any interactions with the cytochrome P-450 isoenzyme system. The acquisition cost of bivalirudin in one study was less than the combination of UFH and glycoprotein IIb/IIIa inhibitors. Bivalirudin combined with provisional glycoprotein IIb/IIIa inhibitors appears to be an acceptable alternative to the standard of care and is superior to UFH alone in PCI.

Topics: Acute Disease; Angioplasty, Balloon, Coronary; Clinical Trials as Topic; Coronary Disease; Drug Interactions; Fibrinolytic Agents; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Thrombin; Thrombosis

Unfractionated heparin given during cardiopulmonary bypass is remarkably immunogenic, as 25% to 50% of postcardiac surgery patients develop heparin-dependent antibodies during the next 5 to 10 days. Sometimes, these antibodies strongly activate platelets and coagulation, thereby causing the prothrombotic disorder, heparin-induced thrombocytopenia. The risk of heparin-induced thrombocytopenia is 1% to 3% if unfractionated heparin is continued beyond the first postoperative week. When cardiac surgery is urgently needed for a patient with acute or subacute heparin-induced thrombocytopenia, options include an alternative anticoagulant (bivalirudin, lepirudin, or danaparoid) or combining unfractionated heparin with a platelet antagonist (epoprostenol or tirofiban). As heparin-induced thrombocytopenia antibodies are transient, unfractionated heparin alone is appropriate in a patient with previous heparin-induced thrombocytopenia whose antibodies have disappeared.

Topics: Anticoagulants; Cardiac Surgical Procedures; Diagnosis, Differential; Female; Heparin; Hirudin Therapy; Hirudins; Humans; Male; Peptide Fragments; Postoperative Complications; Recombinant Proteins; Thrombocytopenia; Thrombosis

The treatment of patients with acute coronary syndromes has changed dramatically over the last several years. Most patients now undergo some form of percutaneous coronary intervention (PCI), which includes either stent placement or percutaneous transluminal coronary angioplasty (PTCA). Along with new medical interventions for acute coronary syndromes comes the need for new antithrombotic therapies. Combination therapy with antiplatelet agents (aspirin, adenosine diphosphate inhibitors), glycoprotein (GP) IIb-IIIa receptor inhibitors, and anticoagulants (unfractionated heparin or low-molecular-weight heparins) is administered, depending on the type of intervention and severity of the coronary lesion. Bivalirudin is a direct thrombin inhibitor that recently was approved as an alternative to heparin in patients undergoing PTCA. Compared with unfractionated heparin, bivalirudin reduces the rate of death, myocardial infarction, or revascularization, with a concurrent reduction in bleeding. This agent offers promise as a replacement for unfractionated heparin in PCI and is being studied in comparison with unfractionated heparin plus GP IIb-IIIa receptor inhibitors in patients undergoing intracoronary stent placement.

Topics: Angioplasty, Balloon, Coronary; Hemorrhage; Heparin, Low-Molecular-Weight; Hirudins; Humans; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Postoperative Complications; Randomized Controlled Trials as Topic; Recombinant Proteins; Thrombin; Thrombocytopenia; Thrombosis; Treatment Outcome

Studies of the anticoagulant effects of hirudin, which is derived from the saliva of the leech Hirudo medicinalis, led to the development of compounds that can directly inhibit thrombin activity without the need for additional cofactors. One of these is the direct thrombin inhibitor bivalirudin, which has recently been approved by the US Food and Drug Administration for use as an anticoagulant in patients with unstable angina undergoing percutaneous transluminal coronary angioplasty.. This is a review of the pharmacologic properties, efficacy, tolerability, and potential cost-effectiveness of bivalirudin in the treatment of ischemic coronary syndromes.. Articles were identified by searches of MEDLINE (1966-September 2001), International Pharmaceutical Abstracts (1970-September 2001), and the Iowa Drug Information Service (1966-September 2001) using the terms bivalirudin and Hirulog. The reference lists of retrieved articles were also reviewed for relevant articles.. Bivalirudin is a synthetic polypeptide that directly inhibits thrombin by binding simultaneously to its active catalytic site and its substrate recognition site. After intravenous administration, peak plasma concentrations occur in 2 minutes. In patients given a 1.0-mg/kg bolus followed by a 2.5-mg/kg per hour infusion, a median activated clotting time of 346 seconds is achieved with little interpatient or intrapatient variability. Clearance of bivalirudin occurs through a combination of renal elimination and proteolytic cleavage, and doses may need to be decreased in the presence of renal dysfunction. In patients undergoing percutaneous coronary interventions, bivalirudin has been associated with equivalent efficacy but lower bleeding rates (P < 0.001) than unfractionated heparin (UFH). Data from the Hirulog Early Reperfusion/Occlusion-2 study suggest no reduction in mortality with bivalirudin compared with heparin when either is added to aspirin and streptokinase in patients with acute myocardial infarction, despite a lower reinfarction rate (P < 0.001). Experience with bivalirudin in patients with unstable angina and heparin-induced thrombocytopenia (HIT), as well as in patients receiving glycoprotein IIb/IIIla inhibitors, is limited. The differences in bleeding rates between bivalirudin and heparin in published clinical trials probably reflect differences in levels of anticoagulation achieved in comparator groups.. Given its high cost, bivalirudin should be reserved for use as an alternative to UFH, primarily in patients with HIT, until clinical trials have more clearly demonstrated its benefits in terms of efficacy or safety.

Topics: Angina, Unstable; Angioplasty, Balloon, Coronary; Anticoagulants; Antithrombins; Clinical Trials as Topic; Hirudin Therapy; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Recombinant Proteins; Thrombocytopenia; Thrombosis

Inhibiting thrombin as a key enzyme of the coagulation cascade is therapeutically useful in thromboembolic diseases. In coronary thrombosis, direct thrombin inhibitors promise to be useful for an efficacious therapy. Hirudin and recombinant or synthetic mimetics like hirulog, argatroban and melagatran have proven their efficacy in clinical studies.. Therapy with direct thrombin inhibitors such as hirudin and analogous substances reduces coronary events. Moreover, the agents are useful for therapy of thromboembolic diseases, especially in the case of heparin induced thrombocytopenia type II.

Topics: Acute Disease; Angina, Unstable; Angioplasty, Balloon, Coronary; Animals; Anticoagulants; Antithrombins; Arginine; Azetidines; Benzylamines; Fibrinolytic Agents; Glycine; Hirudin Therapy; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Pipecolic Acids; Platelet Aggregation Inhibitors; Rabbits; Recombinant Proteins; Sulfonamides; Syndrome; Thrombin; Thromboembolism; Thrombosis; Time Factors

Revascularization procedures and particularly percutaneous transluminal coronary angioplasty are being performed more and more often in patients with unstable coronary artery disease, despite the fact that these procedures are known to carry a higher risk in such patients than in those with stable disease. This article reviews studies that have investigated the potential of modern antithrombotic therapy -- low-molecular-weight heparin, anti-Xa agents, direct antithrombin inhibitors and glycoprotein IIb/IIIa inhibitors -- to reduce the post-procedural event rate in such patients. The results are promising.

Topics: Abciximab; Angina, Unstable; Angioplasty, Balloon, Coronary; Antibodies, Monoclonal; Anticoagulants; Aspirin; Clinical Trials as Topic; Combined Modality Therapy; Diabetes Complications; Drug Therapy, Combination; Eptifibatide; Factor Xa Inhibitors; Heparin, Low-Molecular-Weight; Hirudin Therapy; Hirudins; Humans; Immunoglobulin Fab Fragments; Myocardial Revascularization; Oligosaccharides; Peptide Fragments; Peptides; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Postoperative Complications; Randomized Controlled Trials as Topic; Recombinant Proteins; Risk Factors; Thrombocytopenia; Thrombosis; Time Factors; Tirofiban; Treatment Outcome; Tyrosine

Topics: Animals; Fibrinolytic Agents; Heparin; Hirudin Therapy; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Reperfusion; Streptokinase; Thrombin; Thrombosis

Topics: Animals; Fibrinolytic Agents; Hemostasis; Heparin; Heparin, Low-Molecular-Weight; Hirudins; Humans; Peptide Fragments; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Receptors, Purinergic P2; Recombinant Proteins; Thrombosis; Vitamin K

The quest for an orally active anticoagulant to replace warfarin sodium (Coumadin, Panwarfin, Sofarin) in long-term use has been disappointing. Most advances in oral anticoagulant therapy have involved more judicious and efficacious use of warfarin or one of its analogues. The area of heparin substitutes has experienced some exciting discoveries, with most current interest centered on low-molecular-weight heparins. Their efficacy, safety, and perhaps most important, clinical utility as a once- or twice-daily unmonitored medication have given them a meaningful role in current anticoagulation therapy. Third-generation anticoagulants, such as the direct thrombin inhibitors, are being investigated but are not ready for general clinical use. The role of ancrod (Arvin) from snake venom in patients with heparin-induced thrombocytopenic thrombosis has been clearly established. A practical issue that remains under discussion is the most suitable interaction between fiscal and clinical applications of these medications.

Topics: Ancrod; Anticoagulants; Antithrombins; Female; Fibrinolytic Agents; Heparin; Hirudin Therapy; Hirudins; Humans; Peptide Fragments; Pregnancy; Recombinant Proteins; Thrombosis

Topics: Amino Acid Sequence; Animals; Antithrombins; Blood Platelets; Hemorrhage; Hirudin Therapy; Hirudins; Humans; Molecular Sequence Data; Papio; Peptide Fragments; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Primates; Recombinant Proteins; Thrombin; Thrombosis

Topics: Amino Acid Chloromethyl Ketones; Amino Acid Sequence; Animals; Antithrombins; Blood Coagulation; Cricetinae; Hirudin Therapy; Hirudins; Mice; Models, Molecular; Molecular Sequence Data; Peptide Fragments; Rats; Receptors, Thrombin; Recombinant Proteins; Sequence Alignment; Sequence Homology, Amino Acid; Species Specificity; Substrate Specificity; Thrombin; Thrombosis

Topics: Animals; Anticoagulants; Antithrombin III; Antithrombin III Deficiency; Aprotinin; Blood Coagulation Tests; Cardiopulmonary Bypass; Heparin; Hirudin Therapy; Hirudins; Humans; Intraoperative Complications; Peptide Fragments; Postoperative Complications; Recombinant Proteins; Thrombin; Thrombosis; Warfarin

Hirudin is the most potent and specific known inhibitor of thrombin, the enzyme that plays a key regulatory function in hemostasis and blood coagulation. The importance of thrombosis in cardiovascular disease has recently highlighted the limitations of existing antithrombotic drugs and the potential value of direct thrombin inhibition as an effective approach to antithrombotic therapy. Hirudin and a small peptidomimetic analog--hirulog--are being developed as alternatives to heparin for the treatment of unstable angina, for prevention of abrupt closure and restenosis following coronary angioplasty, for prevention of deep vein thrombosis after major orthopedic surgery, and as an adjunct to fibrinolytic therapy. Direct thrombin inhibitors have several potential advantages over heparin: They can inhibit thrombin bound to clots or extracellular matrices, which are relatively resistant to heparin; they do not require antithrombin III as a cofactor, which may lead to a more predictable dose response; and they are not inhibited by activated platelets, which release platelet factor 4 and other molecules that neutralize heparin. The results of early clinical studies suggest that hirudin and hirulog may be more efficacious and more predictable and may have fewer bleeding complications than heparin for several clinical indications.

Topics: Heparin; Hirudin Therapy; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Structure-Activity Relationship; Thrombin; Thrombolytic Therapy; Thrombosis

Topics: Animals; Anticoagulants; Hirudin Therapy; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Thrombin; Thrombosis

Leeches have been used for various medicinal purposes since before written history. Bloodletting and leeching declined with the advent of modern medicine. Nevertheless, the European medicinal leech has made a comeback in reattachment and plastic surgery. The antithrombotic substance of this leech is the small protein, hirudin, which has recently been cloned and advanced as an antithrombotic. From speculating how hirudin interacted with thrombin and before knowledge of the crystallographic structures of hirudin-thrombin complexes, the bridge-binding double-ligand concept was born and led to the highly specific thrombin inhibitors of the hirulog class. Like heparin, hirulogs and recombinant hirudins are not orally active but should fill needs where heparin and its derivatives have shortcomings. On the other hand, they most likely will be supplanted by small-molecule thrombin inhibitors when sufficiently specific and nontoxic ones are found. Other approaches to antithrombotic therapy include modulating cellular functions of thrombin. Because thrombin has central bioregulatory functions in thrombosis and hemostasis, as well as wound healing, it is an attractive target for antithrombotic intervention.

Topics: Amino Acid Sequence; Animals; Fibrinolytic Agents; Hirudin Therapy; Hirudins; Humans; Leeches; Molecular Sequence Data; Peptide Fragments; Recombinant Proteins; Thrombin; Thrombosis

Previous randomised trials of bivalirudin versus heparin in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) have reported conflicting results, in part because of treatment with different pharmacological regimens. We designed a large-scale trial examining bivalirudin with a post-PCI high-dose infusion compared with heparin alone, the regimens that previous studies have shown to have the best balance of safety and efficacy.. BRIGHT-4 was an investigator-initiated, open-label, randomised controlled trial conducted at 87 clinical centres in 63 cities in China. Patients with STEMI undergoing primary PCI with radial artery access within 48 h of symptom onset who had not received previous fibrinolytic therapy, anticoagulants, or glycoprotein IIb/IIIa inhibitors were randomly assigned (1:1) to receive bivalirudin with a post-PCI high-dose infusion for 2-4 h or unfractionated heparin monotherapy. There was no masking. Glycoprotein IIb/IIIa inhibitor use was reserved for procedural thrombotic complications in both groups. The primary endpoint was a composite of all-cause mortality or Bleeding Academic Research Consortium (BARC) types 3-5 bleeding at 30 days. This trial is registered with ClinicalTrials.gov (NCT03822975), and is ongoing.. Between Feb 14, 2019, and April 7, 2022, a total of 6016 patients with STEMI undergoing primary PCI were randomly assigned to receive either bivalirudin plus a high-dose infusion after PCI (n=3009) or unfractionated heparin monotherapy (n=3007). Radial artery access was used in 5593 (93·1%) of 6008 patients. Compared with heparin monotherapy, bivalirudin reduced the 30-day rate of the primary endpoint (132 events [4·39%] in the heparin group vs 92 events [3·06%] in the bivalirudin group; difference, 1·33%, 95% CI 0·38-2·29%; hazard ratio [HR] 0·69, 95% CI 0·53-0·91; p=0·0070). All-cause mortality within 30 days occurred in 118 (3·92%) heparin-assigned patients and in 89 (2·96%) bivalirudin-assigned patients (HR 0·75; 95% CI 0·57-0·99; p=0·0420), and BARC types 3-5 bleeding occurred in 24 (0·80%) heparin-assigned patients and five (0·17%) bivalirudin-assigned patients (HR 0·21; 95% CI 0·08-0·54; p=0·0014). There were no significant differences in the 30-day rates of reinfarction, stroke, or ischaemia-driven target vessel revascularisation between the groups. Within 30 days, stent thrombosis occurred in 11 (0·37%) of bivalirudin-assigned patients and 33 (1·10%) of heparin-assigned patients (p=0·0015).. In patients with STEMI undergoing primary PCI predominantly with radial artery access, anticoagulation with bivalirudin plus a post-PCI high-dose infusion for 2-4 h significantly reduced the 30-day composite rate of all-cause mortality or BARC types 3-5 major bleeding compared with heparin monotherapy.. Chinese Society of Cardiology Foundation (CSCF2019A01), and a research grant from Jiangsu Hengrui Pharmaceuticals.

Topics: Drug Therapy, Combination; Hemorrhage; Heparin; Humans; Myocardial Infarction; Percutaneous Coronary Intervention; Platelet Glycoprotein GPIIb-IIIa Complex; ST Elevation Myocardial Infarction; Thrombosis

JNJ-64179375 (hereafter JNJ-9375) is a first-in-class, highly specific, large molecule, exosite 1 thrombin inhibitor. In preclinical studies, JNJ-9375 demonstrated robust antithrombotic protection with a wider therapeutic index when compared to apixaban. The purpose of the present study was to examine for the first time the antiplatelet, anticoagulant and antithrombotic effects of JNJ-9375 in a translational model of ex vivo human thrombosis.. Fifteen healthy volunteers participated in a double-blind randomized crossover study of JNJ-9375 (2.5, 25, and 250 μg/mL), bivalirudin (6 μg/mL; positive control), and matched placebo. Coagulation, platelet activation, and thrombus formation were determined using coagulation assays, flow cytometry, and an ex vivo perfusion chamber, respectively.JNJ-9375 caused concentration-dependent prolongation of all measures of blood coagulation (prothrombin time, activated partial thromboplastin time, and thrombin time; P < 0.001 for all) and agonist selective inhibition of thrombin (0.1 U/mL) stimulated platelet p-selectin expression (P < 0.001) and platelet-monocyte aggregates (P = 0.002). Compared to placebo, JNJ-9375 (250 μg/mL) reduced mean total thrombus area by 41.1% (95% confidence intervals 22.3 to 55.3%; P < 0.001) at low shear and 32.3% (4.9 to 51.8%; P = 0.025) at high shear. Under both shear conditions, there was a dose-dependent decrease in fibrin-rich thrombus (P < 0.001 for both) but not platelet-rich thrombus (P = ns for both).. Exosite 1 inhibition with JNJ-9375 caused prolongation of blood coagulation, selective inhibition of thrombin-mediated platelet activation, and reductions in ex vivo thrombosis driven by a decrease in fibrin-rich thrombus formation. JNJ-9375 represents a novel class of anticoagulant with potential therapeutic applications.

Topics: Adult; Antithrombins; Biomarkers; Blood Coagulation; Blood Coagulation Tests; Blood Platelets; Cross-Over Studies; Dose-Response Relationship, Drug; Double-Blind Method; Female; Fibrin; Healthy Volunteers; Hirudins; Humans; Male; P-Selectin; Peptide Fragments; Platelet Activation; Recombinant Proteins; Scotland; Thrombosis; Young Adult

The optimal anti-coagulation strategy for patients with non-ST-elevation myocardial infarction treated with percutaneous coronary intervention is unclear in contemporary clinical practice of radial access and potent P2Y12-inhibitors. The aim of this study was to investigate whether bivalirudin was superior to heparin monotherapy in patients with non-ST-elevation myocardial infarction without routine glycoprotein IIb/IIIa inhibitor use.. In a large pre-specified subgroup of the multicentre, prospective, randomised, registry-based, open-label clinical VALIDATE-SWEDEHEART trial we randomised patients with non-ST-elevation myocardial infarction undergoing percutaneous coronary intervention, treated with ticagrelor or prasugrel, to bivalirudin or heparin monotherapy with no planned use of glycoprotein IIb/IIIa inhibitors during percutaneous coronary intervention. The primary endpoint was the rate of a composite of all-cause death, myocardial infarction or major bleeding within 180 days.. Bivalirudin as compared to heparin during percutaneous coronary intervention for non-ST-elevation myocardial infarction did not reduce the composite of all-cause death, myocardial infarction or major bleeding in non-ST-elevation myocardial infarction patients receiving current recommended treatments with modern P2Y12-inhibitors and predominantly radial access.

Topics: Aged; Anticoagulants; Antithrombins; Female; Hemorrhage; Heparin; Hirudins; Humans; Male; Myocardial Infarction; Non-ST Elevated Myocardial Infarction; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Prasugrel Hydrochloride; Purinergic P2Y Receptor Antagonists; Recombinant Proteins; Stents; Sweden; Thrombosis; Ticagrelor

To compare bleeding and clinical events of patients with stable angina or silent ischemia undergoing percutaneous coronary intervention (PCI) treated with unfractionated heparin (UFH) or bivalirudin.. Few direct comparisons between UFH monotherapy versus bivalirudin exist for patients with stable ischemic heart disease undergoing PCI.. A prospective, investigator-initiated, single-center, single-blinded, randomized trial of UFH versus bivalirudin was conducted. The primary endpoint was all bleeding (major and minor) from index-hospitalization to 30 days post discharge. Secondary endpoints included major adverse cerebral and cardiovascular events (MACCE) and net adverse clinical events (NACE).. Two-hundred-sixty patients were randomized for treatment with either UFH (n = 123) (47%) or bivalirudin (n = 137) (53%) There were no significant differences in baseline clinical and angiographic characteristics between the two groups. Primary endpoint was similar in both groups (10.9% with bivalirudin vs 7.3% with UFH [P = 0.31]). Major bleeding rates were 5.8% and 2.4%, respectively (P = 0.17). There was a higher MACCE (3.5% vs 0%, P = 0.03) and NACE (8.8% vs 2.4%, P = 0.03) rate with bivalirudin compared to UFH, respectively. Bivalirudin had increased odds of NACE (OR = 3.65, 95% CI: 1.00-13.3.6). Death and stent thrombosis rates were low and similar in both groups. Radial access was associated with fewer bleeding events compared to femoral access but not statistically significant (P = 0.29).. Among patients with stable angina or silent ischemia, there was no difference between UFH and bivalirudin in bleeding rates up to 30-days post-PCI. MACCE and NACE were higher among the bivalirudin group. Radial access was associated with a numerically lower rate of bleeding compared with femoral access.

Topics: Aged; Anticoagulants; Coronary Artery Disease; Drug Monitoring; Female; Hemorrhage; Heparin; Hirudins; Humans; Male; Middle Aged; Myocardial Ischemia; Peptide Fragments; Percutaneous Coronary Intervention; Prospective Studies; Recombinant Proteins; Thrombosis; Treatment Outcome

Selection of valve type and procedural anticoagulant may impact bleeding and vascular complications in transfemoral transcatheter aortic valve replacement (TAVR). We sought to compare outcomes by valve [balloon expandable (BE) or non-BE] and anticoagulant [bivalirudin vs. unfractionated heparin (UFH)] type from the BRAVO-3 trial.. BRAVO-3 was a randomized multicenter trial including 500 BE-TAVR and 282 non-BE TAVR patients, randomized to bivalirudin versus UFH. Selection of valve type was at the discretion of the operator but randomization was stratified according to valve type. Total follow up was to 30 days. We examined the incidence of Bleeding Academic Research Consortium type ≥3b bleeding, major vascular complications and all ischemic outcomes at 30-days. Outcomes were adjusted using logistic regression analysis.. Of the trial cohort, 63.9% were treated with BE valves (n = 251 bivalirudin vs. n = 249 UFH) and 36.1% with non-BE valves (n = 140 bivalirudin vs. n = 142 UFH). Patients treated with non-BE valves were older, with higher euroSCORE I. At 30 days, there were nonsignificant differences between the two valve types for adjusted risk of all-cause death (HR 2.07, 95% CI 0.91-4.70, P = 0.084) and major vascular complications (HR 1.78, 95% CI 0.97-3.26, P = 0.062) with non-BE compared with BE valves, but all other outcomes were similar. A significant interaction was observed between valve and anticoagulant type, with lower risk of major vascular complications with bivalirudin compared with UFH in non-BE TAVR (P-interaction = 0.039).. Majority of patients in the BRAVO 3 trial received BE valves. At 30-days, adjusted risk of clinical outcomes was similar with non-BE vs. BE valves. A significant interaction was observed between valve type and procedural anticoagulant for lower risk of major vascular complications with bivalirudin versus UFH in non-BE TAVR.

Topics: Aged, 80 and over; Antithrombins; Aortic Valve; Aortic Valve Stenosis; Cause of Death; Dose-Response Relationship, Drug; Europe; Female; Fibrinolytic Agents; Follow-Up Studies; Heart Valve Prosthesis; Heparin; Hirudins; Humans; Incidence; Infusions, Intravenous; Male; Peptide Fragments; Practice Guidelines as Topic; Prosthesis Design; Recombinant Proteins; Retrospective Studies; Survival Rate; Thrombolytic Therapy; Thrombosis; Time Factors; Transcatheter Aortic Valve Replacement; Treatment Outcome; United States

Bivalirudin has been associated with reduced bleeding and mortality during primary percutaneous coronary intervention for ST-segment elevation myocardial infarction (STEMI). However, increased rates of acute stent thrombosis (AST) have been noted when bivalirudin is discontinued at the end of the procedure, which is perhaps related to this medication's short half-life.. To evaluate the clinical effect of procedure duration on AST when either bivalirudin or heparin plus glycoprotein IIb/IIIa receptor inhibitor (GPI) is used.. An ad hoc analysis of the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) clinical trial was performed between March 1, 2015, and April 30, 2016, on patients who underwent primary percutaneous coronary intervention with stents and were randomized 1:1 to bivalirudin or heparin plus GPI. Defined as the difference between the patient's arrival at the catheterization laboratory and the patient's final angiogram. Participants included 3602 patients with STEMI, aged 18 years or older, who were undergoing primary percutaneous coronary intervention and presenting less than 12 hours from symptom onset.. Clinical events committee-adjudicated definite AST (occurring ≤24 hours after percutaneous coronary intervention).. Among patients included in this analysis, procedure time was identified in 1286 receiving bivalirudin and 1412 receiving heparin plus GPI. Shorter procedures were defined as the lowest quartile of duration (<45 minutes). Patients undergoing shorter procedures were younger and less likely to be hypertensive and smokers. Shorter procedures were less complicated with fewer stents implanted, less multivessel stenting, less thrombus, and less no-reflow. An increased risk of definite AST was associated with shorter than with longer procedures with bivalirudin (7 [2.1%] vs 7 [0.7%]; relative risk, 2.87; 95% CI, 1.01-8.17; P = .04) but not with heparin plus GPI (0 vs 3 [0.3%]; P = .30).. Despite less procedural complexity, shorter primary percutaneous coronary intervention time was associated with an increased risk of AST in patients treated with bivalirudin but not patients treated with heparin plus GPI, possibly because of the rapid offset of bivalirudin's antithrombotic effect during a window of limited oral antiplatelet action.. clinicaltrials.gov Identifier: NCT00433966.

Topics: Acute Disease; Aged; Anticoagulants; Antithrombins; Drug Therapy, Combination; Female; Heparin; Hirudins; Humans; Male; Middle Aged; Operative Time; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Postoperative Complications; Recombinant Proteins; Risk Factors; ST Elevation Myocardial Infarction; Stents; Thrombosis

Early stent thrombosis (ST) within 30 days after primary percutaneous coronary intervention in ST-segment-elevation myocardial infarction is a serious event. We sought to determine the predictors of and risk of mortality after early ST according to procedural antithrombotic therapy.. In a patient-level pooled analysis from the Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) and European Ambulance Acute Coronary Syndrome Angiography (EUROMAX) trials, we examined 30-day outcomes in 4935 patients undergoing primary percutaneous coronary intervention with stent implantation at 188 international sites, randomized to either bivalirudin or heparin±a glycoprotein IIb/IIIa inhibitor (GPI). Early ST occurred in 100 patients (2.0%), 20 of whom (20.0%) died. Bivalirudin was associated with higher rates of early ST compared with heparin±GPI (2.5% versus 1.6%, P=0.04), because of more acute (≤24 h) ST (1.5% versus 0.2%, P<0.0001), with the risk limited to the first 4 hours after percutaneous coronary intervention. The rates of subacute (1-30 days) ST were similar with bivalirudin and heparin±GPI (1.0% versus 1.4%, P=0.24). Among patients with early ST, mortality within 30 days occurred in 4 of 60 (6.7%) bivalirudin-treated patients compared with 16 of 40 (40.0%) heparin±GPI-treated patients (adjusted hazard ratio, 0.12; 95% CI, 0.04-0.39; P=0.0004 and adjusted hazard ratio, 0.122; 95% CI, 0.04-0.39; P=0. 0004). Thus, 30-day mortality attributable to early ST occurred in 4 of 2479 (0.2%) bivalirudin-treated patients versus 16 of 2456 (0.7%) heparin±GPI-treated patients (P=0.007).. In the present large-scale pooled analysis from 2 multicenter randomized trials, early ST was more frequent in patients treated with bivalirudin compared with heparin±GPI because of increased ST within 4 hours after primary percutaneous coronary intervention. However, the mortality attributable to early ST was significantly lower after bivalirudin than after heparin±GPI.. URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00433966 (HORIZONS-AMI) and NCT01087723 (EUROMAX).

Topics: Aged; Blood Vessel Prosthesis Implantation; Electrocardiography; Female; Heparin; Hirudins; Humans; Male; Middle Aged; Myocardial Infarction; Patient Outcome Assessment; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Postoperative Complications; Recombinant Proteins; Stents; Survival Analysis; Thrombosis

Clinical trials have demonstrated an excess of acute stent thrombosis (AST) in acute coronary syndromes patients (ACS) undergoing percutaneous coronary intervention (PCI) with bivalirudin compared to heparin. We aimed to investigate the potential mechanisms responsible for thrombus formation under bivalirudin.. We compared heparin and bivalirudin during PCI for ACS in a prospective monocentre randomized study. Twenty patients were included after coronary angiography and received a loading dose (LD) of 180mg of ticagrelor at the time of PCI. They were randomly assigned to heparin (70UI/kg) intra-venous (IV) bolus or bivalirudin IV bolus of 0.75mg/kg followed by an infusion of 1.75mg/kg/h until the end of the PCI. The VASP index and thrombin generation test were used to assess the course of platelet reactivity (PR) and thrombin generation.. Thrombin generation and PR were identical in both groups at baseline. There was no difference in the course of PR following the LD over time. An optimal PR inhibition was reached 4h after the LD of ticagrelor. Heparin and bivalirudin infusion effectively inhibited thrombin generation during PCI. However, 4h after the end of bivalirudin infusion, thrombin generation had returned to its baseline value whereas in the heparin group it remained significantly inhibited compared to baseline and to the bivalirudin group 4h after the end of the infusion (p<0.01 and p<0.02 respectively).. The present study suggests that the short half-life of bivalirudin and the quick restoration of thrombin activity at a time when optimal PR is not reached may be responsible for acute stent thrombosis. Clinicaltrial.gov: NCT02428725.

Topics: Acute Coronary Syndrome; Administration, Intravenous; Adult; Aged; Aged, 80 and over; Antithrombins; Drug-Eluting Stents; Female; Follow-Up Studies; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Prospective Studies; Recombinant Proteins; Thrombosis

In the HORIZONS-AMI trial, bivalirudin compared to unfractionated heparin (UFH) plus a glycoprotein IIb/IIIa inhibitor (GPI) improved net clinical outcomes in patients undergoing primary percutaneous coronary intervention (PCI) at the cost of an increased rate of acute stent thrombosis. We sought to examine whether these effects are dependent on time to treatment.. The interaction between anticoagulation regimen and symptom onset to first balloon inflation time (SBT) on the 30-day and three-year rates of major adverse cardiac events (MACE) was examined in 3,199 randomised patients according to SBT ≤3 hours versus >3 hours. Among patients with an SBT ≤3 hours, bivalirudin resulted in higher 30-day rates of MACE compared to UFH plus a GPI. Non-significant differences were observed in patients with an SBT >3 hours. Similar results were found for MACE at three years and stent thrombosis and reinfarction at 30 days and three years. By multivariable analysis, bivalirudin was an independent predictor of MACE at 30 days and three years in patients with an SBT ≤3 hours, but not in patients with SBT >3 hours.. Bivalirudin compared to UFH plus a GPI is associated with an increased rate of stent thrombosis and MACE in patients with short SBTs, but not in those with longer SBTs.

Topics: Aged; Anticoagulants; Antithrombins; Cause of Death; Drug Therapy, Combination; Female; Graft Occlusion, Vascular; Heparin; Hirudins; Humans; Male; Middle Aged; Mortality; Myocardial Infarction; Myocardial Revascularization; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Glycoprotein GPIIb-IIIa Complex; Postoperative Complications; Recombinant Proteins; Recurrence; ST Elevation Myocardial Infarction; Stroke; Thrombosis; Time-to-Treatment; Treatment Outcome

Reinfarction after primary percutaneous coronary intervention in patients with ST-segment-elevation myocardial infarction has negative consequences. Little is known about reinfarction after drug-eluting stents and bivalirudin anticoagulation. We, therefore, sought to determine the incidence, predictors, and implications of reinfarction after primary percutaneous coronary intervention in the contemporary era.. Outcomes were assessed in 3202 patients undergoing stent implantation for ST-segment-elevation myocardial infarction in the Harmonizing Outcomes with RevascularIZatiON and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial. Independent predictors of reinfarction and mortality were identified by Cox proportional hazards modeling. The cumulative incidence of reinfarction was 1.8% at 30 days, 4.0% at 1 year, and 6.9% at 3 years. Definite stent thrombosis was responsible for 76.3% of reinfarctions occurring within 30 days and 52.0% of all reinfarctions within 3 years. Independent predictors of reinfarction were current smoking, Killip class ≥2, baseline thrombocytosis, multivessel disease, symptom onset-to-balloon time, and total stent length. Randomization to bivalirudin versus heparin plus a glycoprotein IIb/IIIa inhibitor and use of drug-eluting versus bare metal stents were not significant predictors of reinfarction. Reinfarction was a powerful independent predictor of subsequent cardiac mortality (hazard ratio [95% confidence interval]=7.65 [4.47-13.09]; P<0.0001) and all-cause mortality (hazard ratio [95% confidence interval]=2.88 [1.74-4.78]; P<0.0001).. Despite advances in pharmacotherapy and stents, reinfarction after primary percutaneous coronary intervention is not infrequent, in the contemporary era is most often attributable to stent thrombosis, and is strongly associated with subsequent cardiac and all-cause mortality. Further enhancements in drugs and devices to prevent reinfarction are needed to improve outcomes in high-risk patients with ST-segment-elevation myocardial infarction.. http://www.clinicaltrials.gov. Unique identifier: NCT00433966.

Topics: Acute Disease; Aged; Antithrombins; Drug-Eluting Stents; Electrocardiography; Female; Follow-Up Studies; Heparin; Hirudins; Humans; Incidence; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Glycoprotein GPIIb-IIIa Complex; Postoperative Complications; Prospective Studies; Recombinant Proteins; Recurrence; Risk Factors; Survival Analysis; Thrombosis; Treatment Outcome

The study sought to determine whether rapid access to medical care and reperfusion results in a better prognosis in patients with in-hospital compared with out-of-hospital stent thrombosis (ST) in patients with ST-segment elevation myocardial infarction (STEMI) in the HORIZONS-AMI (Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction) trial.. Whether the prognosis of in-hospital and out-of-hospital ST are similar is uncertain, with conflicting data reported from prior studies.. A total of 3,602 STEMI patients undergoing primary percutaneous coronary intervention (PCI) were randomized to bivalirudin (n = 1,800) versus unfractionated heparin (UFH) plus a glycoprotein IIb/IIIa inhibitor (GPI) (UFH+GPI; n = 1,802). Stents were implanted in 3,202 patients, 156 (4.9%) of whom developed Academic Research Consortium definite/probable ST during 3-year follow-up. We investigated the 1-year clinical outcomes after ST in 54 patients with in-hospital ST compared with 102 patients with out-of-hospital ST.. One year after the ST event, patients with in-hospital compared with out-of-hospital ST had significantly greater mortality (27.8% vs. 10.8%, p < 0.01); most deaths in both groups occurred within 1 week of the ST event. Patients with in-hospital ST also had higher rates of major bleeding (21.2% vs. 6.0%, p < 0.01), but a lower rate of myocardial infarction (56.6% vs. 77.5%, p < 0.01). Subgroup analysis within both in-hospital and out-of-hospital ST groups indicated that subacute ST had the highest mortality. By multivariable analysis, 1-year mortality was significantly increased in patients with in-hospital compared with out-of-hospital ST (adjusted hazard ratio: 4.62, 95% confidence interval: 1.98 to 10.77, p < 0.01). Additional correlates of increased mortality after an ST event included diabetes and randomization to UFH+GPI (vs. bivalirudin).. Following primary PCI for STEMI, more than one-third of all ST events during 3-year follow-up occurred during the index hospital phase. Mortality and major bleeding were significantly higher after in-hospital ST compared with out-of-hospital ST. (Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction; NCT00433966).

Topics: Aged; Female; Follow-Up Studies; Hirudins; Hospital Mortality; Hospitalization; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Stents; Thrombosis; Treatment Outcome

The standard of care for STEMI PCI for the past decade has been aspirin, clopidogrel, heparin, and a glycoprotein IIbIIIa receptor inhibitor (GPI). A bivalirudin strategy was shown to be superior to a GPI strategy in the HORIZONS AMI trial for net adverse clinical events (combined MACE and bleeding). An increased risk of acute stent thrombosis in the bivalirudin arm may have prevented broader adoption of bivalirudin for this indication. We hypothesized that acute stent thrombosis risk could be ameliorated by a 2 h infusion of bivalirudin following STEMI PCI. We implemented a multicenter, prospective registry for all STEMI patients in Vermont treated at a single PCI center. Each patient was routinely pre-loaded with dual antiplatelet therapy and 75% received an unfractionated heparin bolus prior to PCI. The utilization of bivalirudin bolus and continued 2 h infusion after PCI was routine with GPI bailout optional. 128 consecutive STEMI patients underwent primary PCI from October 1, 2008 to September 30, 2009. 92% of primary PCI patients received bivalrudin during and after the procedure with a 9% rate of bail out GPI. There was one case of probable or definite acute stent thrombosis (0.7%), and this single case occurred despite use of bailout GPI. Despite the prolonged infusion of bivalirudin, major bleeding occurred in only 1.7% of STEMI patients. In conclusion, prolonging bivalirudin for 2 h after STEMI PCI may be a promising method to alleviate acute stent thrombosis risk without losing the bleeding complication benefit of the bivalirudin strategy.

Topics: Aged; Antithrombins; Coronary Artery Bypass; Female; Hirudins; Humans; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Platelet Aggregation Inhibitors; Recombinant Proteins; Registries; Stents; Thrombosis; Time Factors

Pediatric physicians regularly face the problem of uncertain procedural anticoagulation in children, especially in neonates. We sought to evaluate the safety, plasma concentration (pharmacokinetics, PK), pharmacodynamics (PD), and dosing guidelines of bivalirudin when used as a procedural anticoagulant in pediatric percutaneous intravascular procedures.. Pediatric subjects undergoing percutaneous intravascular procedures for congenital heart disease were enrolled and received the current weight-based dose used in percutaneous coronary interventions (0.75 mg/kg bolus, 1.75 mg/kg/hr infusion). Blood samples for PK/PD analyses were drawn, and safety was evaluated by monitoring bleeding and thrombosis events. A total of 110 patients (11 neonates, 33 infants, 32 young children, and 34 older children) were enrolled; 106 patients received the protocol dose. The PK/PD response of bivalirudin was predictable and behaved in a manner similar to that in adults. Weight-normalized bivalirudin clearance rates were more rapid in neonates and decreased with increasing age. Bivalirudin concentrations were slightly lower in neonates, with a trend to an increase with age. Activating clotting time response was consistent with adult studies and prolonged in all age groups, and there was reasonable correlation between activating clotting time and bivalirudin plasma concentrations across all age groups. There were few major bleeding (2 of 110, 1.8%) or thrombotic events (9 of 110, 8.2%) reported.. PK/PD response of bivalirudin in the pediatric population is predictable and behaves in a manner similar to that in adults. Using adult dosing, bivalirudin safely provided the expected anticoagulant effect in the pediatric population undergoing intravascular procedures for congenital heart disease.

Topics: Adolescent; Age Factors; Anticoagulants; Cardiac Catheterization; Child; Child, Preschool; Female; Heart Defects, Congenital; Hemorrhage; Hirudins; Humans; Infant; Infant, Newborn; Male; Peptide Fragments; Prospective Studies; Recombinant Proteins; Risk Assessment; Risk Factors; Thrombosis; Treatment Outcome; United States

This study sought to investigate the impact of chronic kidney disease (CKD) in patients undergoing percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) with different antithrombotic strategies.. CKD is associated with increased risk of adverse ischemic and hemorrhagic events after primary PCI for STEMI.. HORIZONS-AMI (Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction) trial was a multicenter, international, randomized trial comparing bivalirudin monotherapy or heparin plus a glycoprotein IIb/IIIa inhibitor (GPI) during primary PCI in STEMI. CKD, defined as creatinine clearance <60 ml/min, was present at baseline in 554 of 3,397 patients (16.3%). Patients were followed for 3 years. Net adverse cardiac event (NACE) was defined as the composite of death, reinfarction, ischemia-driven target vessel revascularization (TVR), stroke or non-coronary artery bypass grafting (CABG)-related major bleeding.. Patients with CKD compared with patients without had higher rates of NACE (41.4% vs. 23.8%, p < 0.0001), death (18.7% vs. 4.4%, p < 0.0001), and major bleeding (19.3% vs. 6.7%, p < 0.0001). Multivariable analysis identified baseline creatinine as an independent predictor of death at 3 years (hazard ratio: 1.51, 95% confidence interval: 1.21 to 1.87, p < 0.001). Patients with CKD randomized to bivalirudin monotherapy versus heparin plus GPI had no significant difference in major bleeding (19.0% vs. 19.6%, p = 0.72) or death (19.0% vs. 18.4%, p = 0.88) at 3 years. In patients with CKD, there was no difference in the rates of TVR in bare-metal stents (BMS) versus drug-eluting stents (DES) at 3 years (14.1% vs. 15.1%, p = 0.8).. STEMI patients with CKD have significantly higher rates of death and major bleeding compared with those without CKD. In patients with CKD, there appears to be no benefit of bivalirudin compared with heparin + GPI, or DES versus BMS during primary PCI in improving clinical outcomes.

Topics: Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Anticoagulants; Chi-Square Distribution; Chronic Disease; Drug-Eluting Stents; Europe; Female; Fibrinolytic Agents; Hemorrhage; Heparin; Hirudins; Humans; Israel; Kaplan-Meier Estimate; Kidney Diseases; Male; Metals; Middle Aged; Myocardial Infarction; Peptide Fragments; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Proportional Hazards Models; Prospective Studies; Prosthesis Design; Recombinant Proteins; Recurrence; Risk Assessment; Risk Factors; Stents; Stroke; Thrombosis; Time Factors; Treatment Outcome; United States

We sought to determine whether a transradial (TR) approach compared with a transfemoral (TF) approach was associated with improved clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) in a post hoc analysis of the HORIZONS-AMI trial. There is a paucity of data comparing the TR approach with the TF approach in patients with STEMI treated with primary PCI and contemporary anticoagulant regimens.. In HORIZONS-AMI, primary PCI for STEMI was performed in 3,340 patients, either by the TR (n=200) or TF approach (n=3,134). Endpoints included the 30-day and one-year rates of major adverse cardiovascular events (MACE: death, reinfarction, stroke or target vessel revascularisation), non CABG-related major bleeding, and net adverse clinical events (NACE: MACE or major bleeding). TR compared to TF access was associated with significantly lower 30-day rates of composite death or reinfarction (1.0% vs. 4.3%, OR 0.23, 95% CI [0.06,0.94], p=0.02), non CABG-related major bleeding (3.5% vs. 7.6%, OR 0.45, 95% CI [0.21,0.95], p=0.03), MACE (2.0% vs. 5.6%, OR 0.35, 95% CI [0.13,0.95], p=0.02), and NACE (5.0% vs. 11.6%,OR 0.42, 95% CI [0.22,0.78], p<0.01). At one year, the TR group still had significantly reduced rates of death or reinfarction (4.0% vs. 7.8%, OR 0.51, 95% CI [0.25,1.02], p=0.05), non CABG-related major bleeding (3.5% vs. 8.1%, OR 0.42, 95% CI [0.20,0.89], p=0.02), MACE (6.0% vs. 12.4%, OR 0.47, 95% CI [0.26,0.83], p<0.01) and NACE (8.5% vs. 17.8%, OR 0.45, 95% CI [0.28,0.74], p<0.001). By multivariable analysis, TR access was an independent predictor of freedom from MACE and NACE at 30 days and one year.. In patients with STEMI undergoing primary PCI with contemporary anticoagulation regimens in the HORIZONS-AMI trial, a TR compared with a TF approach was associated with reduced major bleeding and improved event-free survival.

Topics: Aged; Angioplasty; Antithrombins; Female; Fibrinolytic Agents; Heparin; Hirudins; Humans; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Prospective Studies; Radial Artery; Recombinant Proteins; Thrombosis; Treatment Outcome

Replacing heparin with bivalirudin has been beneficial in patients undergoing coronary intervention and coronary artery bypass. The use of this alternative anticoagulant during peripheral bypass operations has not been studied. Concerns over distal thrombosis using this direct thrombin inhibitor (DTI) prompted a single-arm, open-label, pilot prospective trial of bivalirudin in patients undergoing lower extremity bypass to assess perioperative safety and efficacy.. Between 2006 and 2007, 18 patients met criteria for enrollment and underwent primary lower extremity bypass using bivalirudin. All patients had severe symptomatic atherosclerotic disease requiring lower extremity bypass. Bivalirudin at a bolus dose of 0.75 mg/kg and continuous infusion of 1.75 mg/kg/hr was used as the sole anticoagulant.. Patients (mean age, 67 years) underwent femoral-popliteal (n = 14) or femoral-tibial (n = 4) bypass preferentially using saphenous vein (83%). Mean operative time was 261 minutes, with bivalirudin infusion time of 95 +/- 26 minutes (mean +/- standard deviation). Reliable anticoagulation was achieved with weight-based dosing with activated clotting time values at baseline (systemic) of 131 +/- 92 seconds, during infusion (systemic) of 347 +/- 36 seconds, and from the distal vasculature (limb) of 345 +/- 66 seconds. Distal limb bivalirudin levels were stable at 9755 +/- 3860 ng/mL during clamp occlusion. Mean estimated blood loss was 332 +/- 191 mL with four patients (22%) requiring blood products. One patient required revision of the proximal anastomosis during the initial hospitalization. At 30 days, all bypass operations were patent with improvement of mean ankle-brachial index from 0.57 to 0.81. There were no deaths, myocardial infarctions, or amputations in the 30-day postoperative period. Based on the Thrombolysis in Myocardial Infarction classification for bleeding, one patient had major bleeding (>2 units of packed red blood cells), and three patients had minor bleeding within the first 30 days.. Bivalirudin is a safe and effective anticoagulant for lower extremity bypass operations. Thrombosis beyond the distal clamp was not seen. A comparative trial to standard anticoagulation is warranted.

Topics: Aged; Ankle Brachial Index; Anticoagulants; Arterial Occlusive Diseases; Blood Loss, Surgical; Hemorrhage; Hirudins; Humans; Infusions, Intravenous; Lower Extremity; Ohio; Peptide Fragments; Pilot Projects; Prospective Studies; Recombinant Proteins; Reoperation; Saphenous Vein; Thrombin; Thrombosis; Time Factors; Treatment Outcome; Vascular Patency; Vascular Surgical Procedures

General recommendations indicate that, during a carotid artery stenting (CAS), sufficient unfractionated heparin (UFH) has to be given to maintain the activated clotting time between 250 to 300 seconds. Bivalirudin use is able to reduce postprocedural bleedings in percutaneous interventions when compared with UFH. The study purpose was to evaluate, in a randomized study, the safety and efficacy of bivalirudin versus heparin during CAS, using proximal endovascular occlusion (PEO) as a distal protection device.. From January 2006 to December 2009, 220 patients undergoing CAS using PEO have been randomly assigned to one of the study arms (control arm: 100 UI/kg UFH or bivalirudin arm: 0.75 mg/kg intravenous bolus and intraprocedural infusion at 1.75 mg/kg/h).. Procedural success was achieved in all the patients. No episodes of intraprocedural thrombosis occurred. One major stroke occurred in the bivalirudin arm, and two minor strokes occurred, one in each group. A significant difference in the incidence of postprocedural bleedings was observed between the study groups; bivalirudin use was associated with reduced number of bleedings according to Thrombolysis In Myocardial Infarction criteria.. The use of bivalirudin should be considered a safe and effective anticoagulation regimen during CAS, using PEO as a distal protection device. Bivalirudin use is associated with a reduced incidence of bleedings.

Topics: Aged; Anticoagulants; Balloon Occlusion; Blood Loss, Surgical; Carotid Artery, Internal; Carotid Stenosis; Endovascular Procedures; Female; Heparin; Hirudins; Humans; Male; Peptide Fragments; Recombinant Proteins; Stents; Stroke; Thrombosis; Whole Blood Coagulation Time

Concomitant antithrombotic therapy is essential for the prevention of ischaemic events in percutaneous coronary intervention (PCI) and stenting. With new anticoagulant medications being developed and applied in PCI, this raises the question of possible interactions with platelet and leukocyte activation. We therefore sought to investigate the influence of bivalirudin and heparin in platelet and leukocyte activation in patients undergoing elective PCI. Forty-six patients were recruited consecutively in the setting of the Intracoronary Stenting and Antithrombotic Regimen-Rapid Early Action for Coronary Treatment (ISAR-REACT)-3 trial and were randomly assigned to receive either unfactionated heparin or bivalirudin during elective PCI. Surface expression of CD62P (P-Selectin), CD42b (GPIbalpha), CD40L, PAC-1 on circulating platelets and CD11b, CD14 and CD15 on circulating leukocytes were evaluated by flow cytometry. Cytokine levels of IL-12p70, tumour necrosis factor (TNF), IL-8, IL-6, IL-1beta and IL-10 were determined by cytometric bead array. Platelet surface expression of PAC-1, P-Selectin and GPIbalpha was significantly reduced after PCI in patients receiving bivalirudin as compared to heparin. Similarly, CD11b expression on CD14+ monocytes was diminished after bivalirudin. However, no differences were observed in cytokine levels between the bivalirudin and the heparin group, before or after PCI. In conclusion, our data suggest that bivalirudin may reduce platelet and monocyte activation in patients undergoing elective PCI. Thereby, bivalirudin might reduce periinterventional thrombotic complications.

Topics: Adult; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Anticoagulants; Antigens, CD; Coronary Angiography; Coronary Stenosis; Cytokines; Double-Blind Method; Female; Fibrinolytic Agents; Heparin; Hirudins; Humans; Male; Middle Aged; Monocytes; Peptide Fragments; Platelet Activation; Platelet Aggregation Inhibitors; Platelet Membrane Glycoproteins; Prospective Studies; Recombinant Proteins; Thrombosis; Time Factors; Treatment Outcome

This study sought to evaluate the impact of age on outcomes in patients with moderate- and high-risk non-ST-segment elevation acute coronary syndrome (NSTE-ACS) enrolled in the ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) trial.. Aging-associated changes in physiology and metabolism may alter the risk and benefit of therapeutic strategies from that observed in younger people.. We performed a pre-specified analysis of 30-day and 1-year outcomes in 4 age groups, overall and among those undergoing percutaneous coronary intervention (PCI).. Of 13,819 patients in the ACUITY trial, 3,655 (26.4%) were <55 years of age, 3,940 (28.5%) were 55 to 64 years of age, 3,783 (27.4%) were 65 to 74 years of age, and 2,441 (17.7%) were > or =75 years of age. Older patients had more cardiovascular risk factors and had a higher acuity at presentation. Patients age > or =75 years treated with bivalirudin alone had similar ischemic outcomes, but significantly lower rates of bleeding compared with those treated with heparin and glycoprotein IIb/IIIa inhibitors overall and in the PCI subset. The number needed to treat with bivalirudin alone to avoid 1 major bleeding event was lower in this age group (23 overall and 16 for PCI-treated patients) than in any other.. Ischemic and bleeding complications after NSTE-ACS increase with age. Although ischemic event rates are not statistically different with either bivalirudin alone or a heparin plus glycoprotein IIb/IIIa inhibitor, bleeding complications are significantly less frequent with bivalirudin alone. Because of the substantial risk of bleeding in patients age > or =75 years, the number needed to treat to avoid 1 major bleeding event using bivalirudin alone was the lowest in the elderly group, especially among those undergoing PCI.

Topics: Acute Coronary Syndrome; Aged; Aging; Angioplasty, Balloon, Coronary; Anticoagulants; Coronary Artery Bypass; Enoxaparin; Female; Fibrinolytic Agents; Hemorrhage; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Thrombosis; Treatment Outcome

In the HORIZONS-AMI trial, patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) who were treated with the thrombin inhibitor bivalirudin had substantially lower 30-day rates of major haemorrhagic complications and net adverse clinical events than did patients assigned to heparin plus a glycoprotein IIb/IIIa inhibitor (GPI). Here, we assess whether these initial benefits were maintained at 1 year of follow-up.. Patients aged 18 years or older were eligible for enrolment in this multicentre, open-label, randomised controlled trial if they had STEMI, presented within 12 h after the onset of symptoms, and were undergoing primary PCI. 3602 eligible patients were randomly assigned by interactive voice response system in a 1:1 ratio to receive bivalirudin (0.75 mg/kg intravenous bolus followed by 1.75 mg/kg per h infusion; n=1800) or heparin plus a GPI (control; 60 IU/kg intravenous bolus followed by boluses with target activated clotting time 200-250 s; n=1802). The two primary trial endpoints were major bleeding and net adverse clinical events (NACE; consisting of major bleeding or composite major adverse cardiovascular events [MACE; death, reinfarction, target vessel revascularisation for ischaemia, or stroke]). This prespecified analysis reports data for the 1-year follow-up. Analysis was by intention to treat. Patients with missing data were censored at the time of withdrawal from the study or at last follow-up. This trial is registered with ClinicalTrials.gov, number NCT00433966.. 1-year data were available for 1696 patients in the bivalirudin group and 1702 patients in the control group. Reasons for participant dropout were loss to follow-up and withdrawal of consent. The rate of NACE was lower in the bivalirudin group than in the control group (15.6%vs 18.3%, hazard ratio [HR] 0.83, 95% CI 0.71-0.97, p=0.022), as a result of a lower rate of major bleeding in the bivalirudin group (5.8%vs 9.2%, HR 0.61, 0.48-0.78, p<0.0001). The rate of MACE was similar between groups (11.9%vs 11.9%, HR 1.00, 0.82-1.21, p=0.98). The 1-year rates of cardiac mortality (2.1%vs 3.8%, HR 0.57, 0.38-0.84, p=0.005) and all-cause mortality (3.5%vs 4.8%, HR 0.71, 0.51-0.98, p=0.037) were lower in the bivalirudin group than in the control group.. In patients with STEMI undergoing primary PCI, anticoagulation with bivalirudin reduced the rates of net adverse clinical events and major bleeding at 1 year compared with treatment with heparin plus a GPI. This finding has important clinical implications for the selection of optimum treatment strategies for patients with STEMI.. Cardiovascular Research Foundation, with unrestricted grant support from Boston Scientific Corporation and The Medicines Company.

Topics: Adult; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Anticoagulants; Female; Follow-Up Studies; Hemorrhage; Heparin; Hirudins; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Proportional Hazards Models; Recombinant Proteins; Stents; Survival Rate; Thrombosis; Treatment Outcome

Our study sought to evaluate mechanisms of the current strategies for optimal anticoagulation during percutaneous coronary intervention (PCI).. Thirty-two high risk acute coronary syndrome patients were randomised to bivalirudin and provisional GPIIb/IIIa inhibition (GPIIb/IIIa) or unfractionated heparin (UFH) and mandatory GPIIb/IIIa. Flow cytometric measurements immediately after anticoagulation showed that, unlike UFH, bivalirudin did not activate platelets as indicated by P-selectin expression and fibrinogen binding while decreasing platelet-monocyte aggregates and monocyte expression of tissue factor. UFH released tissue factor pathway inhibitor (TFPI) during and immediately after PCI while bivalirudin (irrespective of GP IIb/IIIa) did not. Lower levels of TFPI with bivalirudin were seen during and immediately after PCI (P<0.01). Thrombin generation as indicated by prothrombin fragment F 1+2 levels was reduced during PCI in the UFH group (P<0.01) but not with bivalirudin. Soluble CD40 ligand is associated with thrombosis and levels were higher in the bivalirudin group irrespective of GPIIb/IIIa at the same stages (P<0.05).. Bivalirudin has some early advantages on platelet activation when compared to UFH. However, there are significant limitations in its mechanism of action, particularly a lack of release of tissue factor pathway inhibitor.

Topics: Acute Coronary Syndrome; Aged; Angioplasty, Balloon, Coronary; Anticoagulants; Aspirin; Biomarkers; Blood Coagulation; CD40 Ligand; Clopidogrel; Drug Therapy, Combination; Female; Fibrinogen; Heparin; Hirudins; Humans; Lipoproteins; Male; Membrane Glycoproteins; Middle Aged; Monocytes; Peptide Fragments; Platelet Activation; Platelet Adhesiveness; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Prothrombin; Recombinant Proteins; Thromboplastin; Thrombosis; Ticlopidine; Treatment Outcome

We assessed the incidence, predictors, and outcomes of gastrointestinal bleeding (GIB) in patients with acute coronary syndromes (ACS).. GIB is a potential hemorrhagic complication in patients with ACS treated with antithrombotic and/or antiplatelet medications. The clinical outcomes associated with GIB in this setting have not been systematically studied.. In the ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) trial, 13,819 patients with moderate- and high-risk ACS, enrolled at 450 centers in 17 countries between August 2003 and December 2005, were randomized to the open-label use of 1 of 3 antithrombin regimens (heparin plus a glycoprotein IIb/IIIa inhibitor, bivalirudin plus a glycoprotein IIb/IIIa inhibitor, or bivalirudin monotherapy).. GIB within 30 days occurred in 178 patients (1.3%). Older age, baseline anemia, longer duration of study drug administration before angiogram, smoking, ST-segment deviation>or=1 mm, and diabetes were identified as independent predictors of GIB. On multivariable analysis, GIB was strongly associated with 30-day all-cause mortality (hazard ratio [HR]: 4.87 [interquartile range (IQR) 2.61 to 9.08], p<0.0001), cardiac mortality (HR: 5.35 [IQR 2.71 to 10.59], p<0.0001), and composite ischemia (HR: 1.94 [IQR 1.14 to 3.30], p=0.014), as well as with 1-year all-cause mortality (HR: 3.97 [IQR 2.64 to 5.99], p<0.0001), cardiac mortality (HR: 3.77 [IQR 2.14 to 6.63], p<0.0001), myocardial infarction (HR: 1.74 [IQR 1.01 to 3.02], p=0.047), and composite ischemia (HR: 1.90 [IQR 1.37 to 2.64], p=0.0001). Patients who experienced GIB had significantly higher rates of stent thrombosis compared with patients without GIB (5.8% vs. 2.4%, p=0.009).. GIB is a serious condition in the scenario of ACS and is independently associated with mortality and ischemic complications.

Topics: Acute Coronary Syndrome; Age Factors; Aged; Angioplasty, Balloon, Coronary; Anticoagulants; Clopidogrel; Coronary Artery Bypass; Female; Gastrointestinal Hemorrhage; Heparin; Hirudins; Humans; Incidence; Ischemia; Length of Stay; Male; Middle Aged; Multivariate Analysis; Myocardial Infarction; Peptide Fragments; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Risk Assessment; Sex Factors; Stents; Thrombosis; Ticlopidine

Advances in coronary angioplasty and adjunct pharmacology have improved patient outcomes after primary percutaneous coronary intervention (PCI) in acute myocardial infarction (AMI). However, several areas for improvement remain. Hemorrhagic complications, which are common in patients receiving intense anticoagulant and antiplatelet agents during primary PCI to suppress ischemia, have been strongly associated with early and late mortality. Moreover, restenosis after bare-metal stents (BMSs) frequently results in symptom recurrence and the need for repeat rehospitalization and revascularization procedures. Newer pharmacologic agents and drug-eluting stents may address both of these issues.. In the HORIZONS-AMI trial, 3,602 patients with AMI undergoing primary PCI were prospectively randomized to unfractionated heparin plus routine use of glycoprotein (GP) IIb/IIIa inhibitors versus the direct thrombin inhibitor bivalirudin plus provisional use of GP IIb/IIIa inhibitors reserved for predefined thrombotic complications. In a second randomization, 3,011 eligible patients were randomly assigned to either a polymer-based paclitaxel-eluting stent or to an otherwise identical BMS. The study was powered for the assessment of sequential safety and efficacy end points for each specific randomization, with clinical end points assessed at 30 days, 1 year, and then annually for 5 years.. The ongoing HORIZONS-AMI trial will determine whether bivalirudin monotherapy reduces bleeding complications and improves overall event-free survival compared with unfractionated heparin plus the routine use of GP IIb/IIIa inhibitors in patients undergoing primary PCI for AMI. Furthermore, this study will determine whether paclitaxel-eluting stents safely reduce rates of ischemic target lesion revascularization compared with BMSs in the setting of primary PCI.

Topics: Adult; Aged; Angioplasty, Balloon, Coronary; Anticoagulants; Combined Modality Therapy; Coronary Angiography; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug-Eluting Stents; Follow-Up Studies; Heparin, Low-Molecular-Weight; Hirudins; Humans; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Probability; Prospective Studies; Recombinant Proteins; Reference Values; Research Design; Risk Assessment; Stents; Survival Rate; Thrombosis; Time Factors

Whether bivalirudin is superior to unfractionated heparin in patients with stable or unstable angina who undergo percutaneous coronary intervention (PCI) after pretreatment with clopidogrel is unknown.. We enrolled 4570 patients with stable or unstable angina (with normal levels of troponin T and creatine kinase MB) who were undergoing PCI after pretreatment with a 600-mg dose of clopidogrel at least 2 hours before the procedure; 2289 patients were randomly assigned in a double-blind manner to receive bivalirudin, and 2281 to receive unfractionated heparin. The primary end point was the composite of death, myocardial infarction, urgent target-vessel revascularization due to myocardial ischemia within 30 days after randomization, or major bleeding during the index hospitalization (with a net clinical benefit defined as a reduction in the incidence of the end point). The secondary end point was the composite of death, myocardial infarction, or urgent target-vessel revascularization.. The incidence of the primary end point was 8.3% (190 patients) in the bivalirudin group as compared with 8.7% (199 patients) in the unfractionated-heparin group (relative risk, 0.94; 95% confidence interval [CI], 0.77 to 1.15; P=0.57). The secondary end point occurred in 134 patients (5.9%) in the bivalirudin group and 115 patients (5.0%) in the unfractionated-heparin group (relative risk, 1.16; 95% CI, 0.91 to 1.49; P=0.23). The incidence of major bleeding was 3.1% (70 patients) in the bivalirudin group and 4.6% (104 patients) in the unfractionated-heparin group (relative risk, 0.66; 95% CI, 0.49 to 0.90; P=0.008).. In patients with stable and unstable angina who underwent PCI after pretreatment with clopidogrel, bivalirudin did not provide a net clinical benefit (i.e., it did not reduce the incidence of the composite end point of death, myocardial infarction, urgent target-vessel revascularization, or major bleeding) as compared with unfractionated heparin, but it did significantly reduce the incidence of major bleeding. (ClinicalTrials.gov number, NCT00262054.)

Topics: Aged; Angina Pectoris; Angina, Unstable; Angioplasty, Balloon, Coronary; Anticoagulants; Clopidogrel; Double-Blind Method; Female; Hemorrhage; Heparin; Hirudins; Humans; Incidence; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Platelet Aggregation Inhibitors; Premedication; Recombinant Proteins; Recurrence; Risk; Stents; Thrombosis; Ticlopidine

Bivalirudin, a direct thrombin inhibitor binds specifically and reversibly to both fibrin-bound and unbound thrombin. Bivalirudin is approved for use as an anticoagulant in patients undergoing percutaneous coronary intervention. The OASIS-5 trial presented a significant increase in cardiac catheter thrombosis for the pentasaccharid fondaparinux compared to enoxaparin. Catheter thrombosis has never been reported in any trial using bivalirudin. Our study compared the development of catheter thrombosis for bivalirudin, enoxaparin, and unfractionated heparin in a controlled in-vitro environment. Ten healthy male volunteers were pretreated with aspirin 500 mg 2 hours before venesection of 50 ml of blood. The seven groups of anticoagulant combinations tested were: UFH, UFH + eptifibatide, enoxaparin, enoxaparin + eptifibatide, bivalirudin bolus, bivalirudin + eptifibatide, bivalirudin bolus + continuous infusion. The blood/anticoagulant mix continuously circulated through a cardiac guiding catheter for 60 minutes or until the catheter became blocked with thrombus. Thrombus development was assessed by weighing each catheter before and after the procedure. Electron microscopy was used to quantify the degree of erythrocyte, platelet and fibrin deposition. Following anticoagulation with bolus dose bivalirudin, the catheter was invariably occluded with thrombus after 33 minutes of circulation. However, a continuous infusion of Bivalirudin prevented the development of occlusive catheter thrombosis. In the bolus bivalirudin group the mean thrombus weight was significantly greater than in all other groups (p-value < 0.01 in all analyses). Bivalirudin given as a bolus was not sufficient to prevent cardiac catheter thrombosis in our in-vitro study. However, a continuous infusion of bivalirudin had similar anti-thrombotic efficacy compared to other treatment strategies.

Topics: Anticoagulants; Aspirin; Cardiac Catheterization; Enoxaparin; Eptifibatide; Erythrocytes; Fibrin; Fibrinolytic Agents; Heparin; Hirudins; Humans; In Vitro Techniques; Male; Microscopy, Electron, Scanning; Peptide Fragments; Peptides; Perfusion; Platelet Aggregation Inhibitors; Recombinant Proteins; Thrombosis

This study sought to determine if the efficacy of bivalirudin alone versus heparin plus a glycoprotein (GP) IIb/IIIa inhibitor is dependent upon the duration of clopidogrel pre-treatment in patients undergoing percutaneous coronary intervention (PCI) in the ACUITY (Acute Catheterization and Urgent Intervention Triage strategY) trial.. The administration of a clopidogrel loading dose several hours before PCI reduces the risk of periprocedural thrombotic events.. Patients with an acute coronary syndrome were randomized to heparin plus a GP IIb/IIIa inhibitor (control), bivalirudin plus a GP IIb/IIIa inhibitor, or bivalirudin alone. Dose and timing of clopidogrel were left to the investigator's discretion.. Of 13,819 patients randomized, 7,789 underwent PCI. When clopidogrel was initiated at any time before angiography or within 30 min after PCI, randomization to bivalirudin alone (n = 2,284) or control (n = 2,189) was associated with similar ischemic outcomes (8.2% vs. 8.3%, risk ratio: 0.98, 95% confidence interval: 0.81 to 1.20). Those patients who received clopidogrel >30 min after PCI or not at all experienced an increase in ischemic events when randomized to bivalirudin alone (n = 290) versus control (n = 317) (14.1% vs. 8.5%, risk ratio: 1.66, 95% confidence interval: 1.05 to 2.63). Major bleeding was significantly less frequent in patients treated with bivalirudin alone.. This post-hoc analysis suggests that in acute coronary syndrome patients, as long as clopidogrel is administered before or within 30 min of PCI treatment with bivalirudin alone is similarly effective to heparin plus a GP IIb/IIIa inhibitor in suppressing 30-day ischemic events with significantly less bleeding. If it is anticipated that clopidogrel will be given late or not at all after PCI, bivalirudin alone may be associated with worse ischemic outcomes. (Comparison of Angiomax Versus Heparin in Acute Coronary Syndromes; NCT00093158).

Topics: Acute Coronary Syndrome; Adult; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Anticoagulants; Clopidogrel; Coronary Angiography; Drug Administration Schedule; Drug Therapy, Combination; Female; Hemorrhage; Heparin; Hirudins; Humans; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Risk Assessment; Thrombosis; Ticlopidine; Time Factors; Treatment Outcome; Troponin; Young Adult

Treatment with the direct thrombin inhibitor bivalirudin, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, results in similar suppression of ischemia while reducing hemorrhagic complications in patients with stable angina and non-ST-segment elevation acute coronary syndromes who are undergoing percutaneous coronary intervention (PCI). The safety and efficacy of bivalirudin in high-risk patients are unknown.. We randomly assigned 3602 patients with ST-segment elevation myocardial infarction who presented within 12 hours after the onset of symptoms and who were undergoing primary PCI to treatment with heparin plus a glycoprotein IIb/IIIa inhibitor or to treatment with bivalirudin alone. The two primary end points of the study were major bleeding and combined adverse clinical events, defined as the combination of major bleeding or major adverse cardiovascular events, including death, reinfarction, target-vessel revascularization for ischemia, and stroke (hereinafter referred to as net adverse clinical events) within 30 days.. Anticoagulation with bivalirudin alone, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, resulted in a reduced 30-day rate of net adverse clinical events (9.2% vs. 12.1%; relative risk, 0.76; 95% confidence interval [CI] 0.63 to 0.92; P=0.005), owing to a lower rate of major bleeding (4.9% vs. 8.3%; relative risk, 0.60; 95% CI, 0.46 to 0.77; P<0.001). There was an increased risk of acute stent thrombosis within 24 hours in the bivalirudin group, but no significant increase was present by 30 days. Treatment with bivalirudin alone, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, resulted in significantly lower 30-day rates of death from cardiac causes (1.8% vs. 2.9%; relative risk, 0.62; 95% CI, 0.40 to 0.95; P=0.03) and death from all causes (2.1% vs. 3.1%; relative risk, 0.66; 95% CI, 0.44 to 1.00; P=0.047).. In patients with ST-segment elevation myocardial infarction who are undergoing primary PCI, anticoagulation with bivalirudin alone, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, results in significantly reduced 30-day rates of major bleeding and net adverse clinical events. (ClinicalTrials.gov number, NCT00433966 [ClinicalTrials.gov].).

Topics: Adult; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Anticoagulants; Antithrombins; Combined Modality Therapy; Drug Therapy, Combination; Female; Hemorrhage; Heparin; Hirudins; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Recurrence; Stents; Stroke; Thrombosis

The coronary artery bypass grafting (CABG) heparin-induced thrombocytopenia thrombosis syndrome (HITTS) on- and off-pump safety and efficacy (CHOOSE-ON) trial was designed as a safety and efficacy trial of bivalirudin for use in anticoagulation during cardiopulmonary bypass (CPB) in patients with confirmed or suspected HIT and (or) antiplatelet factor 4/heparin (anti-PF4/H) antibodies.. In an open-label, multicenter trial, 50 patients were enrolled prospectively. The primary study endpoint was in-hospital acute procedural success, defined as the absence of death, Q-wave myocardial infarction (MI), repeat operation for coronary revascularization, and stroke at day seven after surgery or hospital discharge, whichever occurred first. The secondary study endpoints were procedural success, defined as the absence of death, Q-wave MI, repeat operation for coronary revascularization, and stroke, at 30 days and 12 weeks after surgery. Perioperative blood loss, transfusions, and the incidence of major bleeding events were also captured.. There were 49 patients treated with bivalirudin of which 43 had acute HIT and thrombosis syndrome (HITTS) with antibodies at time of surgery. Procedural success in-hospital or at 7 days was achieved in 46 (94%) patients. At day 30 procedural success was achieved in 42 (86%) patients, and after 12 weeks in 40 (82%) patients. Mean intraoperative blood loss was 575 +/- 524 mL, and mean 24-hour postoperative blood loss was 998 +/- 595 mL. Forty-one (84%) patients received transfusions before day 7 or discharge with a mean of 5.6 +/- 3.8 units of red blood cells, 8.6 +/- 7.2 units of platelets, and 6.0 +/- 4.7 units of fresh frozen plasma. No differences in outcome among bivalirudin-treated patients were observed between those in the overall group and those with moderately impaired renal function (n = 10).. The current investigation expands the experience of safe and effective anticoagulation with bivalirudin during CPB to patients with confirmed or suspected HIT and anti-PF4/H antibodies, including in the setting of impaired renal function.

Topics: Acute Disease; Aged; Aged, 80 and over; Antibodies; Anticoagulants; Blood Loss, Surgical; Cardiopulmonary Bypass; Erythrocyte Transfusion; Female; Heparin; Hirudins; Humans; Intraoperative Care; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Syndrome; Thrombocytopenia; Thrombosis; Time Factors; Treatment Outcome

Thrombosis is not uncommon in children with serious medical conditions. Unfractionated heparin, the most commonly used anticoagulant in the acute management of thrombosis, has significant pharmacologic limitations, especially in infants. Newer anticoagulants have improved properties relative to heparin, and this may enhance the outcome in children.. To determine dosing, and to assess the safety and efficacy of bivairudin for infants with thrombosis.. Infants <6 months old were chosen for this pilot study as they may most benefit from a direct thrombin inhibitor because of their physiologically low antithrombin levels. This was an open label, dose-finding and safety study. Patients received one of three bolus doses and one of two initial infusion doses with subsequent dosing adjusted utilizing the activated partial thromboplastin time. Safety was assessed by specific bleeding endpoints. Efficacy was determined by reassessing the initial imaging study at 48-72 h and by measurement of molecular markers of thrombin generation.. Sixteen patients completed the study. All three bolus doses resulted in therapeutic anticoagulation, as did both initial infusion doses. A dose-response effect was noted for the continuous infusion but not the bolus dosing. Two patients met the study criteria for major bleeding, both with gross hematuria, which resolved with a reduction in the bivalirudin infusion rate. In terms of efficacy, 37.5% of patients had complete or partial resolution of their thrombosis by 48-72 h. There was a significant decrease in all three molecular markers of thrombin generation.. This study demonstrates the potential utility of bivalirudin in the pediatric population.

Topics: Anticoagulants; Female; Hirudins; Humans; Infant; Infant, Newborn; Male; Partial Thromboplastin Time; Peptide Fragments; Pilot Projects; Prospective Studies; Recombinant Proteins; Thrombosis; Treatment Outcome

Platelet-leukocyte aggregates have been implicated in atherogenesis. This study was designed to determine the influence in vivo of a direct thrombin inhibitor, bivalirudin, compared with unfractionated heparin (UFH) plus the GP IIb-IIIa inhibitor eptifibatide (E) on platelet reactivity, the formation of platelet-leukocyte aggregates, and leukocyte activation.. Blood was taken before and after percutaneous coronary intervention (PCI) from 60 patients randomized to UFH+E (n=26) or bivalirudin (n=34). Platelet function and the formation in vivo of platelet-monocyte aggregates (PMA) and platelet-neutrophil aggregates (PNA) were assessed with the use of flow cytometry. Myeloperoxidase (MPO) elaborated during leukocyte activation was measured by ELISA.. Compared with those treated with bivalirudin, patients treated with UFH+E exhibited a 45% decrease in the capacity of platelets to bind fibrinogen (p=0.006) but a 2-fold increase in platelet surface expression of P-selectin (p=0.04) in samples taken from the coronary ostium before PCI. Platelet-leukocyte aggregation in vivo was greater (PMA=2-fold, p=0.04; PNA=3-fold, p=0.006) with UFH+E as was the concentration in blood of MPO (1.5-fold, p=0.007).. Increased platelet surface expression of P-selectin, augmented platelet-leukocyte aggregation in vivo, and consequent activation of leukocytes was seen before PCI in blood from patients treated with UFH+E compared with bivalirudin. Benefits associated with decreased platelet aggregation when PCI is performed with UFH plus GP IIb-IIIa inhibition may be partially offset by increased platelet-leukocyte aggregation.

Topics: Anticoagulants; Cells, Cultured; Drug Combinations; Eptifibatide; Female; Heparin; Hirudins; Humans; Leukocytes; Male; Middle Aged; P-Selectin; Peptide Fragments; Peptides; Platelet Aggregation; Platelet Aggregation Inhibitors; Recombinant Proteins; Thrombosis

Unfractionated heparin and its antidote, protamine sulfate, allow for rapid and reversible anticoagulation during cardiac surgery with cardiopulmonary bypass, yet limitations exist, including a variable dose-response, dependence on a cofactor for anticoagulant effect, and antigenic potential. This trial was performed to evaluate the safety and efficacy of bivalirudin as an alternative to heparin with protamine reversal in on-pump cardiac surgery.. We conducted a randomized, open-label, multicenter trial comparing heparin with protamine reversal to bivalirudin in patients undergoing cardiac surgery with cardiopulmonary bypass. The primary objective was to demonstrate comparable rates of in-hospital procedural success defined as freedom from death, Q-wave myocardial infarction, stroke, or repeat revascularization. Twenty-one institutions enrolled 101 patients randomized to bivalirudin and 49 patients to heparin treatment.. The primary end point of procedural success was not significantly different between the bivalirudin arm and the heparin/protamine arms at 7 days, 30 days, or 12 weeks' follow-up. Adequate anticoagulation was achieved in all patients. Secondary end points including mortality, 24-hour blood loss, overall incidence of transfusions, and duration of surgery were similar between the two arms.. Bivalirudin is a safe and effective anticoagulant for patients undergoing a wide range of cardiac surgical procedures with cardiopulmonary bypass. Procedural success rates with bivalirudin were similar to rates in patients receiving heparin anticoagulation, with no difference in mortality. Avoidance of blood stasis and attention to the intraoperative medical management of patients is critical for successful use of bivalirudin during cardiopulmonary bypass.

Topics: Aged; Anticoagulants; Cardiopulmonary Bypass; Female; Heparin; Heparin Antagonists; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Postoperative Complications; Protamines; Recombinant Proteins; Thrombocytopenia; Thrombosis

Patients with diabetes who undergo percutaneous coronary intervention (PCI) are at high risk for thrombotic complications following the procedure. We sought to compare the anti-thrombotic effect of bivalirudin to that of eptifibatide plus unfractionated heparin in diabetic patients undergoing elective PCI. Thirty diabetic patients were randomized to receive during PCI either bivalirudin (bivalirudin group, n=15) or eptifibatide plus heparin (eptifibatide group, n=15) at standard dosing regimens. The drugs were continued for 20 minutes (bivalirudin) or 18 hours (eptifibatide) after PCI. Blood thrombogenicity was assessed using the Badimon ex vivo perfusion chamber. Each patient underwent two perfusion studies - at baseline (on aspirin and clopidogrel) and 15-20 minutes following PCI. Perfusion studies were performed at rheologic conditions of low and high shear rates (LSR, HSR). Porcine aortic tunica media served as the thrombogenic substrate. Aortic specimens were stained for total platelet-thrombus and fibrin deposition. Thrombus area was measured using computerized planimetry. There were no differences in clinical characteristics or baseline thrombus area between the two groups. Total platelet-thrombus area was reduced significantly in both groups, but the degree of reduction was lower in the bivalirudin group compared with the eptifibatide group (HSR: 69.5% vs. 89.3% reduction, respectively, P=0.04; LSR: 50.6% vs. 73.2%, P=0.03). Fibrin deposition was reduced in both groups by 47-49%. In conclusion, both bivalirudin and the combination of eptifibatide plus heparin, given to diabetic patients during PCI, achieved marked reductions in total thrombus formation and fibrin deposition. However, glycoprotein IIb/IIIa inhibition by eptifibatide caused a more pronounced reduction in thrombus formation.

Topics: Aged; Angioplasty, Balloon, Coronary; Anticoagulants; Diabetes Complications; Drug Therapy, Combination; Eptifibatide; Female; Fibrinolytic Agents; Heparin; Hirudins; Humans; Male; Middle Aged; P-Selectin; Peptide Fragments; Peptides; Platelet Aggregation Inhibitors; Recombinant Proteins; Thromboplastin; Thrombosis

Bivalirudin (Angiomax) is increasingly used as a substitute for heparin in a variety of percutaneous coronary interventions, and data on its usage in saphenous vein graft interventions are limited. This retrospective, observational study evaluated the efficacy and safety of bivalirudin compared with heparin as an antithrombotic regimen in patients who underwent saphenous vein graft intervention with distal protection devices. We found that bivalirudin use is clinically safe and feasible, with fewer vascular and ischemic complications compared with heparin.

Topics: Aged; Aged, 80 and over; Anticoagulants; Antithrombins; Coronary Artery Disease; Female; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Postoperative Complications; Recombinant Proteins; Retrospective Studies; Saphenous Vein; Stents; Thrombosis; Treatment Outcome

This study evaluated differences in efficacy and safety outcomes with bivalirudin compared with unfractionated heparin (UFH) in patients with cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation (VA ECMO). We performed a retrospective study at an academic medical center that included patients greater than 18 years of age supported with VA ECMO due to cardiogenic shock from January 2009 to February 2021. The primary endpoint was ECMO-associated thrombotic events normalized to duration of ECMO support. Secondary safety endpoints included major bleeding (per ELSO criteria) and blood product administration. Overall, 143 patients were included in our analysis with 54 having received bivalirudin and 89 having received UFH. Median duration of ECMO support was 92 (interquartile range, 56-172) hours. ECMO-associated thrombotic events per ECMO day were significantly less among those that received bivalirudin ( P < 0.001). In adjusted regression, bivalirudin was independently associated with an increased time to thrombosis when compared with UFH (Exp[B] -3.8; 95% confidence interval, 1.7-8.8; P = 0.002). Patients receiving bivalirudin experienced less major bleeding events ( P = 0.02) with less total red blood cell and fresh frozen plasma administration ( P = 0.04 and P = 0.03, respectively). Bivalirudin is a safe and efficacious alternative to UFH in patients requiring VA ECMO for cardiogenic shock.

Topics: Antithrombins; Extracorporeal Membrane Oxygenation; Hemorrhage; Heparin; Humans; Retrospective Studies; Shock, Cardiogenic; Thrombosis

Topics: Anticoagulants; Extracorporeal Membrane Oxygenation; Heparin; Humans; Peptide Fragments; Pulmonary Embolism; Recombinant Proteins; Retrospective Studies; Thrombocytopenia; Thrombosis

VA-ECMO is commonly used for patients in cardiogenic shock (CS) or refractory cardiac arrest (CA) undergoing PCI for ACS. In this setting at high risk of both thrombotic and hemorrhagic complications, optimal anti-thrombotic therapy remains ill-defined. We hypothesized that an anti-thrombotic therapy comprising a parenteral anticoagulant (bivalirudin) and a parenteral anti-platelet agent (cangrelor) may prove safe and effective in this scenario. From November 2019 to December 2021, 14 patients received at least one dose of cangrelor (starting dose: 0.125 μg/kg/min) plus bivalirudin, without background aspirin, in the context of PCI and VA-ECMO for ACS-related CS/CA, and were included in this study. Efficacy endpoint was occurrence of thrombotic events and safety endpoint was major bleeding occurrence. Median age was 58 years. The majority (64%) presented with refractory CA. A thrombotic event occurred in 14%, while major bleeding occurred in 21% patients. One patient experienced arterial thrombosis after VA-ECMO arterial cannula removal, another experienced ischemic cerebellar stroke without functional sequelae. Bleeding events were: 29% BARC 3a, 14% BARC 3b, and 7% BARC 5b. Overall in-hospital mortality was 50%. Cangrelor was continued for 5 (4-10) days; temporary discontinuation was necessary in 36%, either for VA-ECMO cannula removal or for bleeding events. A low dose of cangrelor, associated with standard-intensity anticoagulation with bivalirudin was a feasible anti-thrombotic strategy in patients undergoing PCI during VA-ECMO support for ACS-related CS/CA. Bleeding events rates outweighed thrombotic events rates in this critically-ill population, although the observed rates were lowest among available studies.

Topics: Extracorporeal Membrane Oxygenation; Hemorrhage; Humans; Middle Aged; Percutaneous Coronary Intervention; Retrospective Studies; Shock, Cardiogenic; Thrombosis; Treatment Outcome

Topics: Anticoagulants; Antithrombins; Cardiovascular Diseases; Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; Stents; Thrombosis; Treatment Outcome

Direct thrombin inhibitors (DTIs) are usually monitored with the activated partial thromboplastin time (aPTT) or activated clotting time (ACT). Both are complex assays with multiple enzymatic steps, and performance may be influenced by physiologic and pathologic factors unrelated to the DTI. Simpler systems, such as clot-based dilute thrombin time (dTT) and chromogenic anti-factor IIa assays, have been developed for monitoring DTIs, but there is limited data on their performance in clinical settings.. Medical records of patients who received bivalirudin between March 2020 and April 2022 at a single institution were reviewed for demographic data and adverse outcomes. Plasma samples drawn for aPTT testing were analyzed with chromogenic anti-IIa and dTT bivalirudin assays. Results were compared to bivalirudin dosing.. Results of aPTT assays from 32 patients were compared with the chromogenic (n = 136) and dTT (n = 120) bivalirudin assays. Correlations between the aPTT and the chromogenic and dTT assays were poor (Spearman coefficients 0.55 and 0.62, respectively). There was a stronger correlation when results of the chromogenic and dTT assays were compared to each other (Spearman coefficient 0.92). When assay results were compared to bivalirudin dose, there were stronger correlations with the chromogenic and dTT assays than with the aPTT (Spearman coefficients 0.51, 0.63 and 0.22, respectively).. There was considerable variation between results of specific bivalirudin assays and the aPTT. While bivalirudin assay results correlated better with administered drug dose, suggesting improving reliability, more studies are needed to determine if there is correlation between testing and clinical outcomes.

Topics: Antithrombins; Blood Coagulation; Hirudins; Humans; Reproducibility of Results; Thrombosis

Extracorporeal membrane oxygenation (ECMO) contributes to coagulopathy, necessitating systemic anticoagulation to prevent thrombosis. Traditionally, unfractionated heparin (UFH) has been the anticoagulant of choice, however, due to many inadequacies new evidence suggests benefit with the use of direct thrombin inhibitors. This retrospective cohort sought to evaluate the safety and efficacy of bivalirudin compared to UFH in ECMO patients. Primary endpoints included incidence of bleeding and thrombosis. Percent time in therapeutic range (TR), time to achieve TR and number of dose titrations required to maintain TR were calculated to assess efficacy of institutional protocols. Overall incidence of thrombosis was low, with one event in the bivalirudin group and no events in the UFH group. No difference was found in rates of bleeding between groups (6% vs . 10%, P = 0.44). Bivalirudin yielded higher percent time in TR (86% vs. 33%, P < 0.001), faster time to TR (2 vs . 18 hr, P < 0.001) and required fewer dose adjustments to maintain TR (2 vs . 11, P < 0.001) compared to UFH. These results suggest bivalirudin and UFH are associated with similar rates of bleeding and thrombosis in patients requiring ECMO support. Our results demonstrate the favorable pharmacokinetic profile of bivalirudin, and its ability to consistently maintain TR when compared to UFH.

Topics: Adult; Anticoagulants; Antithrombins; Extracorporeal Membrane Oxygenation; Fibrinolytic Agents; Hemorrhage; Heparin; Hirudin Therapy; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombosis; Treatment Outcome

To assess the effectiveness and safety of bivalirudin compared with heparin monotherapy in elderly patients undergoing percutaneous coronary intervention (PCI).. Bivalirudin is recommended for periprocedural use in patients undergoing PCI who are of high bleeding risk. However, its safe and efficacious use in elderly patients, a typical high bleeding risk cohort, in real world practice is yet to be reported.. In this single center, real-world observational study, 4736 consecutive elderly patients who underwent PCI were enrolled. Of these, 1240 were treated with bivalirudin and 3496 with heparin according to the periprocedural anticoagulation strategies of PCI. The primary outcome was 12-month net adverse clinical events (NACE) defined as a composite of cardiac death, myocardial infarction, stroke, revascularization, or any bleeding. Propensity score matching (PSM) was used to balance baseline characteristics between groups.. After PSM, bivalirudin was found to be associated with lower rates of NACE (19.1% vs. 24.7%, p = 0.002), cardiac death (2.7% vs. 4.3%, p = 0.038), and any bleeding (10.0% vs. 12.9%, p = 0.023) compared to heparin monotherapy. No differences were found in the incidences of myocardial infarction, stroke, revascularization, stent thrombosis (0.1% vs. 0.1%, p = 1.000), and major bleedings (0.5% vs. 0.5%, p = 1.000) between the two patient groups.. In this real-world observational study, periprocedural use of bivalirudin in elderly patients who underwent PCI was associated with less cardiac death and any bleeding compared to heparin monotherapy, without increased risk of stent thrombosis.

Topics: Aged; Anticoagulants; Coronary Artery Disease; Death; Hemorrhage; Heparin; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; Stroke; Thrombosis; Treatment Outcome

Heparin-induced thrombocytopenia (HIT) is an immune-mediated adverse drug reaction associated with thrombosis. Clinical scoring systems and the presence of anti-platelet factor 4 (anti-PF4)/heparin antibodies determine the diagnosis.. The clinical presentation of intraventricular and multiple arterial thrombi is remarkable. SARS-CoV-2 infection likely contributed to a hypercoagulable state. The management of patients with HIT undergoing cardiac surgery is challenging. If surgery cannot be delayed, then treatment with bivalirudin is recommended. Additionally, this drug is recommended for PCI. Bivalirudin is safe and well-tolerated in both procedures.

Topics: Acenocoumarol; Anticoagulants; Arginine; COVID-19; COVID-19 Drug Treatment; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Percutaneous Coronary Intervention; Pipecolic Acids; Recombinant Proteins; SARS-CoV-2; Sulfonamides; Thrombocytopenia; Thrombosis

Bivalirudin is a direct thrombin inhibitor that is being increasingly used for anticoagulation in children after ventricular assist device (VAD) implantation. While the data on bivalirudin use in pulsatile flow VADs are growing, reports on its use in patients on continuous flow (CF) VAD as well as comparisons of associated outcomes with unfractionated heparin (UFH) remain limited.. Retrospective cohort study.. Single tertiary-quaternary referral center.. All patients less than 21 years old on CF-VAD support who received bivalirudin or UFH for anticoagulation between the years 2016 and 2020.. Not applicable.. Clinical characteristics compared between the cohorts included time to target range of anticoagulation, markers of hemolysis, and prevalence of hemocompatibility-related adverse events such as major hemorrhagic complications, ischemic stroke, and pump thrombosis. In 42 unique patients (41 HeartWare HVAD [Medtronic, Minneapolis, MN], one HeartMate 3 LVAD [Abbott Laboratories, Abbott Park, IL]) during the study period, a total of 67 encounters of IV anticoagulation infusions (29 UFH and 38 bivalirudin) were retrospectively reviewed. In comparison with use of UFH, bivalirudin was associated with lesser odds of major bleeding complications (odds ratio [OR], 0.29; 95% CI, 0.09-0.97; p = 0.038). We failed to identify any difference in odds of major thrombotic complications (OR, 2.53; 95% CI, 0.47-13.59; p = 0.450). Eight of the patients (28%) on UFH were switched to bivalirudin due to hemorrhagic or thrombotic complications or inability to achieve therapeutic anticoagulation, while two of the patients (5%) on bivalirudin were switched to UFH due to hemorrhagic complications. Bivalirudin was used for a "washout" in eight cases with concern for pump thrombosis-six had resolution of the pump thrombosis, while two needed pump exchange.. Use of bivalirudin for anticoagulation in patients on CF-VAD support was associated with lesser odds of hemorrhagic complications compared with use of UFH. Bivalirudin "washout" was successful in medical management of six of eight cases of possible pump thrombosis.

Topics: Adult; Anticoagulants; Antithrombins; Child; Heart-Assist Devices; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombosis; Treatment Outcome; Young Adult

Unfractionated heparin is the most commonly utilized anticoagulant in extracorporeal membrane oxygenation (ECMO) due to clinician familiarity, ease of reversal, and low cost compared to alternative agents. However, heparin's anticoagulant effect can be unpredictable and its use accompanies a risk of heparin induced thrombocytopenia (HIT). Successful use of bivalirudin as an alternative to heparin in non-HIT ECMO patients has previously been described. However, there is a paucity of data regarding its utilization in patients with confirmed HIT on ECMO.. This single-center retrospective chart review at Cleveland Clinic Main Campus included 12 ECMO patients who were managed with bivalirudin for a new diagnosis of HIT. Descriptive statistical analyses were performed utilizing median with interquartile range and number with percent as appropriate.. Of the 12 patients included, median ECMO duration was 328.5 (218.8-502.1) h and venoarterial ECMO was the most common configuration. No patients experienced the primary outcome of in-circuit thrombosis while on bivalirudin. One patient developed a deep vein thrombosis 22.5 h after switching from heparin to bivalirudin. Major bleeding occurred during bivalirudin therapy in 8 (66.7%) patients.. Overall, our study results suggest that bivalirudin is effective for the management of HIT and did not show evidence of in-circuit thrombosis. A high incidence of major bleeding was observed with bivalirudin use within this study. Clinicians should view bivalirudin as an acceptable agent for the treatment of HIT in the ECMO population, but must consider bleeding risk given the lack of effective reversal agents.

Topics: Anticoagulants; Extracorporeal Membrane Oxygenation; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombocytopenia; Thrombosis

Topics: Animals; Antithrombins; Blood Vessel Prosthesis; Carotid Arteries; Carotid Artery Injuries; Cell Proliferation; Coated Materials, Biocompatible; Disease Models, Animal; Endothelial Cells; Hirudins; Indoles; Male; Peptide Fragments; Polymers; Polytetrafluoroethylene; Recombinant Proteins; Swine; Swine, Miniature; Thrombosis; Wettability

Topics: Amblyomma; Animals; Antibodies; Anticoagulants; Antidotes; Antithrombins; Aspirin; Drug Development; Drug Discovery; Female; Fibrinolytic Agents; Gene Library; Heparin; Hirudins; Humans; Male; Peptide Fragments; Percutaneous Coronary Intervention; Proteomics; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Swine; Thrombin; Thrombosis; Ticks; Transcriptome

There is a paucity of data regarding the use of direct thrombin inhibitors such as bivalirudin for children on extracorporeal life support (ECLS). We sought to compare the outcomes of children on ECLS anticoagulated with bivalirudin versus heparin. Patients transitioned from heparin to bivalirudin were treated as a separate group. A single-institution, retrospective review of all consecutive children (neonate to 18 years) placed on ECLS in the cardiac or pediatric intensive care units was performed (June 2018-December 2019). Data collected included demographics, anticoagulation strategy, number of circuit interventions, blood product use on ECLS, survival to decannulation, and survival to discharge. Fifty-four children were placed on ECLS for a total of 56 runs. Demographics and venovenous versus venoarterial ECLS were similar. The bivalirudin group had longer median duration of support compared to the heparin group--11.0 days [IQR 6.2, 23.1] versus 3.3 days [2.1, 6.2], P < .001. Patients switched from heparin to bivalirudin had a similar duration of support (10.3 days [8.3, 18.3]) as those on bilvalirudin alone. However, there was no difference in red blood cell, fresh frozen plasma, or platelet transfusions. There was no difference in the number of circuit interventions, survival to decannulation or discharge. The freedom to first circuit intervention was longer with bivalirudin compared to heparin. Our data suggest that even with longer pediatric ECLS runs on bivalirudin, there were no differences in the outcomes between the heparin and bivalirudin groups, with longer freedom from first circuit intervention with bivalirudin. While this is the largest reported series comparing children on ECLS anticoagulated with heparin versus bivalirudin, larger studies are needed to determine the optimal anticoagulation strategy for this diverse and complicated group of children.

Topics: Adolescent; Anticoagulants; Blood Coagulation; Child; Child, Preschool; Critical Illness; Drug Substitution; Extracorporeal Membrane Oxygenation; Female; Hemorrhage; Heparin; Hirudins; Hospitals, High-Volume; Humans; Infant; Intensive Care Units, Pediatric; Male; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Stroke; Thrombosis

Although heparin has previously been the anticoagulant of choice during mechanical circulatory support (MCS), there is a lack of consistency in dose-response in pediatric patients. Bivalirudin offers more consistent dose-response in adults; however, there are limited data for pediatrics use.. The purpose was to characterize the usage, dosage, and safety profile of bivalirudin when used for pediatric MCS in a tertiary care pediatric hospital.. A retrospective review of pediatric patients receiving bivalirudin for extracorporeal membrane oxygenation/ventricular assist device (ECMO/VAD) anticoagulation was conducted. The primary outcome was the average dose of bivalirudin. Additional outcomes included initial and maximum bivalirudin dose, time to first therapeutic activated partial thromboplastin time (aPTT), time within goal aPTT range, bleeding and clotting complications, and cost. Data were compared between ECMO and VAD patients.. Thirty-four patients were included. The median dose of bivalirudin was 0.37 mg/kg/h (interquartile range [IQR] = 0.21-0.56), with a maximum dose of 0.62 mg/kg/h (IQR = 0.33-0.91). VAD patients had a higher median and maximum dose as compared with ECMO patients. Patients achieved their therapeutic goal in a median of 6.1 hours and averaged 61.9% time within therapeutic aPTT. One patient had significant hemorrhage, whereas 3 patients had clotting requiring a circuit change. Bivalirudin acquisition cost was higher than heparin.. Bivalirudin dosing in ECMO and VAD patients is consistent with dosing seen in previous reports but may be higher in VAD patients. Comparative studies between heparin and bivalirudin are necessary to compare cost-effective outcomes for pediatric patients.

Topics: Adult; Anticoagulants; Blood Coagulation; Child; Child, Preschool; Cost-Benefit Analysis; Dose-Response Relationship, Drug; Extracorporeal Membrane Oxygenation; Female; Heart-Assist Devices; Hirudins; Humans; Male; Partial Thromboplastin Time; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombosis

In its severe manifestation, coronavirus disease 2019 (COVID-19) compromises oxygenation in a manner that is refractory to maximal conventional support and requires escalation to extracorporeal membrane oxygenation (ECMO). Maintaining ECMO support for extended durations requires a delicately balanced anticoagulation strategy to maintain circuit viability by preventing thrombus deposition while avoiding excessive anticoagulation yielding hemorrhage-a task that is complicated in COVID-19 secondary to an inherent hypercoagulable state. Bivalirudin, a member of the direct thrombin inhibitor drug class, offers potential advantages during ECMO, including to its ability to exert its effect by directly attaching to and inhibiting freely circulating and fibrin-bound thrombin. Herein, the successful use of an anticoagulation strategy using the off-label use of a continuous infusion of bivalirudin in a case of severe hypoxemic and hypercarbic respiratory failure caused by COVID-19 requiring venovenous ECMO is reported. Importantly, therapeutic anticoagulation intensity was achieved rapidly with stable pharmacokinetics, and there was no need for any circuit interventions throughout the patient's 27-day ECMO course. In COVID-19, bivalirudin offers a potential option for maintaining systemic anticoagulation during ECMO in a manner that may mitigate the prothrombotic nature of the underlying pathophysiologic state.

Topics: Aged; Anticoagulants; Antithrombins; COVID-19; COVID-19 Nucleic Acid Testing; Extracorporeal Membrane Oxygenation; Female; Hirudins; Humans; Peptide Fragments; Polymerase Chain Reaction; Recombinant Proteins; Respiratory Insufficiency; SARS-CoV-2; Thrombosis; Treatment Outcome

Antithrombogenicity, anti-inflammation, and rapid re-endothelialization are central requirements for the long-term success of cardiovascular stents. In this work, a plant-inspired phenolic-amine chemistry strategy was developed to combine the biological functions of a plant polyphenol, tannic acid (TA), and the thrombin inhibitor bivalirudin (BVLD) for tailoring the desired multiple surface functionalities of cardiovascular stents. To realize the synergistic modification of TA and BVLD on a stent surface, an amine-bearing coating of plasma polymerized allylamine was firstly prepared on the stent surface, followed by the sequential conjugation of TA and BVLD in alkaline solution based on phenolic-amine chemistry (i.e., Michael addition reaction). TA and BVLD were successfully immobilized onto the stent surface with considerable amounts of 330 ± 12 and 930 ± 80 ng/cm

Topics: Amines; Antithrombins; Hirudins; Humans; Inflammation; Peptide Fragments; Polyphenols; Recombinant Proteins; Stents; Tannins; Thrombosis

An early-term infant with uncomplicated perinatal history was found to have a large thrombus in the aortic arch after he failed regular newborn critical congenital heart defect screen. He responded well to bivalirudin thrombolytic and tissue-plasminogen activator (tPA) combination therapy, with a significant resolution of the thrombus. The infant tolerated hospital admission well with no significant complications. He was discharged home on daily aspirin at 2 weeks of life. To our knowledge, the combination therapy approach with bivalirudin and tPA is the first one reported in the literature in the neonatal age group.

Topics: Age Factors; Antithrombins; Aorta, Thoracic; Aortic Diseases; Hirudins; Humans; Infant, Newborn; Male; Peptide Fragments; Recombinant Proteins; Thrombolytic Therapy; Thrombosis

Extracorporeal membrane oxygenation is a life-sustaining therapy for severe respiratory failure. Extracorporeal membrane oxygenation circuits require systemic anticoagulation that creates a delicate balance between circuit-related thrombosis and bleeding-related complications. Although unfractionated heparin is most widely used anticoagulant, alternative agents such as bivalirudin have been used. We sought to compare extracorporeal membrane oxygenation circuit thrombosis and bleeding-related outcomes in respiratory failure patients receiving either unfractionated heparin or bivalirudin for anticoagulation on venovenous extracorporeal membrane oxygenation support.. Retrospective cohort study.. Single-center, cardiothoracic ICU.. Consecutive patients requiring venovenous extracorporeal membrane oxygenation who were maintained on anticoagulation between 2013 and 2020.. IV bivalirudin or IV unfractionated heparin.. Primary outcomes were the presence of extracorporeal membrane oxygenation in-circuit-related thrombotic complications and volume of blood products administered during extracorporeal membrane oxygenation duration. One hundred sixty-two patients receiving unfractionated heparin were compared with 133 patients receiving bivalirudin for anticoagulation on venovenous extracorporeal membrane oxygenation. In patients receiving bivalirudin, there was an overall decrease in the number of extracorporeal membrane oxygenation circuit thrombotic complications (p < 0.005) and a significant increase in time to circuit thrombosis (p = 0.007). Multivariable Cox regression found that heparin was associated with a significant increase in risk of clots (Exp[B] = 2.31, p = 0.001). Patients who received bivalirudin received significantly less volume of packed RBCs, fresh frozen plasma, and platelet transfusion (p < 0.001 for each). There was a significant decrease in the number major bleeding events in patients receiving bivalirudin, 40.7% versus 11.7%, p < 0.001.. Patients receiving bivalirudin for systemic anticoagulation on venovenous extracorporeal membrane oxygenation experienced a decrease in the number of extracorporeal membrane oxygenation circuit-related thrombotic events as well as a significant decrease in volume of blood products administered.

Topics: Adult; Anticoagulants; Antithrombins; Erythrocyte Transfusion; Extracorporeal Membrane Oxygenation; Female; Hemorrhage; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Plasma; Platelet Transfusion; Recombinant Proteins; Retrospective Studies; Thrombosis

Localized drug delivery with sustained elution characteristics from nanocarrier coated stents represents a viable therapeutic approach to circumvent concerns related to coronary stent therapy. We fabricated a Sirolimus (SRL) and Bivalirudin (BIV) releasing nanoparticles (NPs) coated stent for concurrent mitigation of vascular restenosis and acute stent thrombosis. SRL NPs were prepared by nanoprecipitation method whereas the BIV vesicles were generated using hydrophobic ion pair approach followed by micellization phenomenon. MTT assay and confocal microscopic analysis indicated superior anti-proliferative activity and higher cellular uptake of SRL NPs into human coronary artery smooth muscle cells, respectively. DSC and ATR-FTIR techniques confirmed the formation of complex between BIV and phosphatidylglycerol via some weak physical interactions. More than 2 fold rise in log P value was obtained for DSPG-BIV at 3:1 M ratio compared with native BIV solution. The SAXS analysis indicated formation of oligolamellar vesicles of DSPG-BIV complex which was preferentially entrapped into lipophilic lamellae of vesicles. APTT, PT, and TT tests revealed that the BIV vesicles caused significant prolongation of clotting time compared to native BIV solution. The SEM analysis showed uniform and defect free stent coating. In vitro release study demonstrated that SRL and BIV were eluted in a sustained manner from coated stents.

Topics: Coronary Restenosis; Drug-Eluting Stents; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Scattering, Small Angle; Sirolimus; Stents; Thrombosis; X-Ray Diffraction

The efficacy and safety of bivalirudin in percutaneous coronary intervention (PCI) has always been a hot topic in perioperative antithrombotic therapy, but there are still some controversies. So studies are needed to provide more evidence, especially the real world study which includes patients excluded from previous RCT studys. Our study aimed to investigate these information and analyze the independent predictors of postoperative adverse events.A retrospective study enrolled 1416 patients underwent PCI in Tianjin Chest Hospital from May 2016 to October 2017. The incidence of stent-thrombosis and net clinical adverse events, including all-cause death, myocardial infarction, stroke, urgent target-vessel revascularization and bleeding, were followed up for 30 days and 1 year. Logistic regression and COX regression were respectively used to analyze independent predictors of bleeding events within 30-days, and independent predictors of Major adverse cardiovascular and cerebrovascular events (MACCE) in patients with stent implantation within 1-year.Seven hundred six patients were treated with bivalirudin while 710 with unfractionated heparin (UFH). The proportions of diabetes, hypertension, anemia, myocardial-infarction history, PCI history, moderate-to-severe renal-impairment, gastrointestinal-bleeding history in the bivalirudin group were significantly higher (P < .05). Women, anemia were independent risk factors for bleeding within 30-days (P < .05). Among 682 patients with stent implantation in bivalirudin group, anemia, Body Mass Index (BMI) >25 kg/m2, KILLIP ≥2, ejection fraction (EF) <45%, eGFR <60 ml/minutes were independent risk factors for MACCE, while Statins, proton pump inhibitor (PPI) were independent protective factors for MACCE with-in 1-year (P < .05).Bivalirudin have good anticoagulant effect and lower bleeding risk during PCI, especially in patients with higher bleeding risk. In patients treated with bivalirudin, female, anemia were independent predictors of bleeding within 30-days, BMI >25 kg/m2, anemia, KILLIP ≥2, EF <45%, eGFR <60 ml/minutes were independent risk factors and Statins, PPI were independent protective factors of MACCE within 1-year.

Topics: Aged; Aged, 80 and over; Antithrombins; Coronary Disease; Female; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Percutaneous Coronary Intervention; Perioperative Care; Postoperative Hemorrhage; Recombinant Proteins; Retrospective Studies; Risk Factors; Sex Factors; Stents; Thrombosis; Treatment Outcome

Early hepatic artery thrombosis (HAT) after liver transplantation is a serious complication that frequently results in graft loss and the need for retransplantation. Although studies have reported on various operative and endovascular treatment approaches, pharmacologic strategies for the prevention or management of HAT are not well defined. Patients with blood clotting disorders, those with a contraindication to heparin, and those who have previously developed HAT represent unique challenges in management.. We present the case of a 9-month-old male with a hypercoagulable state who developed early HAT after two liver transplants, despite the use of postoperative therapeutic heparin infusion.. The patient successfully underwent a third liver transplant using intraoperative and postoperative bivalirudin infusion, a direct thrombin inhibitor. Rotational thromboelastometry (ROTEM) was used to guide anticoagulation and blood product administration in the perioperative period. At 1.5 years post-transplant, the patient has good graft function with patent hepatic vasculature. This case demonstrates the innovative use of bivalirudin anticoagulant therapy and viscoelastic methodologies to improve outcomes in hypercoagulable liver transplant recipients.

Topics: Antithrombins; Hepatic Artery; Hirudins; Humans; Infant; Liver Transplantation; Male; Ornithine Carbamoyltransferase Deficiency Disease; Peptide Fragments; Postoperative Complications; Recombinant Proteins; Thrombosis

Ventricular assist devices (VADs) are an increasingly common therapy for end-stage heart failure across all ages as a bridge to recovery or transplant and more recently as destination therapy. With increasing experience and difficulties with establishing therapeutic heparin levels, we have begun to explore the effectiveness of direct thrombin inhibitors in this patient population. This is a retrospective review of all long-term VAD patients, both adult and pediatric, who were anticoagulated with bivalirudin between January 2009 and January 2016. The starting dose was 0.3 mg/kg/hr, and dose was titrated for a goal partial thromboplastin time (PTT) of 70-100. There were 14 patients (13 males, 5 ≤18 years) with 17 episodes of bivalirudin therapy. The median age on initiation was 45 years (range, 15 days-67 years) with 10 episodes associated with a HeartWare HVAD, five a HeartMate II, and two with a Berlin Heart EXCOR. The predominant indication of bivalirudin therapy was suspected pump thrombosis (13/17). The median time from VAD insertion to initiation of bivalirudin was 116 days (range, 3-1,870) with the median duration of therapy being 21 days (range, 3-113). In patients with pump thrombosis, the mean baseline lactate dehydrogenase (LDH) was 229 ± 64 U/L, peak 690 ± 380 U/L, and decreased to 330 ± 243 U/L when bivalirudin was stopped. The outcomes following suspected pump thrombosis included: transitioned to warfarin (n = 7), death in two destination therapy patients who did not undergo pump exchange, transplantation (n = 2), and pump exchange (n = 2). A major bleeding complication occurred in only one patient. Our experience highlights the potential use of bivalirudin in a heterogenous VAD population. Although these initial results suggest some potential role for direct thrombin inhibitors for use in long-term VADs, larger prospective studies are required to support these preliminary observations and to determine who may benefit from direct thrombin inhibitors (DTIs) and the side effect profile in this patient population.

Topics: Adult; Aged; Antithrombins; Blood Coagulation; Child; Child, Preschool; Female; Heart Failure; Heart-Assist Devices; Hirudins; Humans; Infant, Newborn; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombosis; Treatment Outcome; Young Adult

Venous thromboembolism has increasing significance in hospitalized pediatric patients. Patients who have life-threatening or limb-threatening thrombotic events require thrombolysis in addition to anticoagulation. In patients who show signs of heparin resistance or heparin-induced thrombocytopenia, it is imperative to identify alternative therapeutic options. We present a child in whom bivalirudin was used for systemic anticoagulation during catheter-directed thrombolysis along with tissue plasminogen activator (Alteplase

Topics: Antithrombins; Catheterization; Child, Preschool; Drug Resistance; Fibrinolytic Agents; Heparin; Hirudins; Humans; Male; Peptide Fragments; Prognosis; Recombinant Proteins; Thrombolytic Therapy; Thrombosis; Tissue Plasminogen Activator

Pump thrombosis is a serious left ventricular assist device complication, though there are no guidelines regarding its treatment. The main aim of this study was to describe a strategy of intravenous anticoagulation as the initial treatment in these patients and then to compare intravenous heparin with bivalirudin.. All consecutive patients who received a HeartWare left ventricular assist device from July 2009 to March 2019 were retrospectively analysed. Patients developing a pump thrombosis were selected, and treatment, outcomes and complications were recorded.. During this period of time (116 months), 220 patients underwent HeartWare left ventricular assist device implantation and 57 developed pump thrombosis, with an incidence rate of first pump thrombosis of 0.17 events per patient-year of support (incidence rate of all episodes of pump thrombosis: 0.30 events per patient-year of support). All the patients were initially treated medically, predominantly with either intravenous heparin (n = 26) or bivalirudin (n = 16). Patients treated with bivalirudin during the first pump thrombosis episode had less subsequent re-thrombosis episodes (18.7% vs 57.7%, p < 0.05). In addition, percentage time in therapeutic range was greater for bivalirudin compared with heparin (68.5% ± 16.9% vs 37.4% ± 31.0%, p < 0.01). During the first pump thrombosis episode, 26.3% of the patients needed surgery (left ventricular assist device exchange (n = 8), transplant (n = 6) or decommissioning (n = 1)). The overall survival at 1 year was 61.4%, and there was no significant difference in survival.. Left ventricular assist device thrombosis is a serious life-threatening complication; hence, we propose an initial conservative management of pump thrombosis with enhanced intravenous anticoagulation with either intravenous heparin or bivalirudin, with surgery reserved for refractory cases.

Topics: Adult; Antithrombins; Conservative Treatment; Female; Heart Failure; Heart-Assist Devices; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombosis

Extracorporeal membrane oxygenation (ECMO) induces hemostatic alterations that may contribute to hematological complications. Unfractionated heparin (UFH) is the mainstay antithrombotic in ECMO and depends on antithrombin III (AT III) to exhibit its actions. However, it bears the risk for heparin-induced thrombocytopenia. Bivalirudin is a direct thrombin inhibitor and is inherently not dependent on AT III.. To assess the efficacy and safety profiles of UFH compared with bivalirudin during ECMO support.. We retrospectively reviewed 52 adult patients who were supported by ECMO from 1 January 2013 to 1 September 2018. Among them, 33 received UFH and 19 received bivalirudin. We analyzed their 7-day rate of composite thrombotic, bleeding, and mortality episodes while on anticoagulation.. There were no statistical differences in the 7-day rate of composite thrombosis (33.3% vs 26.3%; P = 0.60), major bleeding (18.2% vs 5.3%; P = .24), 30-day mortality, (42.4% vs 26.3%; P = .37), or in-hospital mortality (45.5% vs 36.8%; P = .58). The percentage of time activated partial thromboplastin time (aPTT) was within the therapeutic range was higher with bivalirudin (50% vs 85.7%; P = .007).. This study suggests that UFH and bivalirudin are associated with similar rates of thrombosis, major bleeding, and mortality events in patients supported by ECMO. However, it was observed that bivalirudin consistently maintained aPTT within the therapeutic range in comparison to UFH.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anticoagulants; Extracorporeal Membrane Oxygenation; Female; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombocytopenia; Thrombosis; Young Adult

Thrombotic and bleeding complications have historically been major causes of morbidity and mortality in pediatric ventricular assist device (VAD) support. Standard anticoagulation with unfractionated heparin is fraught with problems related to its heterogeneous biochemical composition and unpredictable pharmacokinetics. We sought to describe the utilization and outcomes in children with paracorporeal VAD support who are treated with direct thrombin inhibitors (DTIs) antithrombosis therapy. Retrospective multicenter review of all pediatric patients (aged <19 years) treated with a DTI (bivalirudin or argatroban) on paracorporeal VAD support, examining bleeding and thrombotic adverse events. From May 2012 to 2018, 43 children (21 females) at 10 centers in North America, median age 9.5 months (0.1-215 months) weighing 8.6 kg (2.8-150 kg), were implanted with paracorporeal VADs and treated with a DTI. Diagnoses included cardiomyopathy 40% (n = 17), congenital heart disease 37% (n = 16; single ventricle n = 5), graft vasculopathy 9% (n = 4), and other 14% (n = 6). First device implanted included Berlin Heart EXCOR 49% (n = 21), paracorporeal continuous flow device 44% (n = 19), and combination of devices in 7% (n = 3). Adverse events on DTI therapy included; major bleeding in 16% (n = 7) (2.6 events per 1,000 patient days of support on DTI), and stroke 12% (n = 5) (1.7 events per 1,000 patient days of support on DTI). Overall survival to transplantation (n = 30) or explantation (n = 8) was 88%. This is the largest multicenter experience of DTI use for anticoagulation therapy in pediatric VAD support. Outcomes are encouraging with lower major bleeding and stroke event rate than that reported in literature using other anticoagulation agents in pediatric VAD support.

Topics: Adolescent; Antithrombins; Arginine; Child; Child, Preschool; Female; Heart-Assist Devices; Hemorrhage; Hirudins; Humans; Infant; Male; North America; Peptide Fragments; Pipecolic Acids; Recombinant Proteins; Retrospective Studies; Stroke; Sulfonamides; Thrombosis; Treatment Outcome

This study aimed to evaluate the antithrombotic efficacy between bivalirudin and unfractionated heparin (UFH) on radial artery thrombosis (RAT) during transradial coronary intervention (TRI) by optical coherence tomography (OCT).. We consecutively reviewed a total of 307 patients who underwent radial artery OCT inspection after TRI in our centre from October 2017 to January 2019; afterwards, 211 screened patients were divided into the UFH group (. In this present study, the use of bivalirudin was associated with a higher risk of RAT than UFH. It highlighted UFH should be a more considerable choice to prevent radial artery access thrombosis in TRI.

Topics: Catheterization, Peripheral; Female; Fibrinolytic Agents; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Percutaneous Coronary Intervention; Radial Artery; Recombinant Proteins; Risk Adjustment; Thrombosis; Tomography, Optical Coherence; Treatment Outcome

Use of optical coherence tomography (OCT) adds an assessment of thrombus burden remaining on stents after PCI for acute coronary syndromes. Potential variations in stent-related thrombus burden can be documented by OCT as a function of peri-procedural pharmacology supporting the use of OCT in future hypothesis testing. Bivalirudin remains a reliable and expensive alternative to heparin in cases of HIT or patients at high bleeding risk during transfemoral PCI.

Topics: Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; Stents; Thrombosis; Tomography, Optical Coherence; Treatment Outcome

This study aimed to assess the efficacy and safety of bivalirudin compared with UFH in high bleeding risk patients with ACS undergoing PCI in current practice.. All consecutive high-bleeding-risk patients who underwent PCI for ACS at the First Affiliated Hospital of Zhengzhou University from January to September 2019 were retrospectively analyzed. The 30-day primary outcome was a composite of major bleeding, myocardial infarction, all-cause death, or stroke (net adverse clinical events [NACEs]), and the secondary outcomes at 30 days included a composite of myocardial infarction, stoke, or all-cause death (major adverse cardiovascular events [MACEs]), each component of the primary outcome, target vessel revascularization (TVR) and stent thrombosis (ST). Besides, we assessed angina-related health status at 30 days, the length of hospital stay, and hospitalization costs. A logistic regression model was used to adjust for baseline differences. Consistency of the treatment effect of bivalirudin for NACEs and MACEs compared with UFH was evaluated in 15 prespecified subgroups.. From January to September 2019, 823 patients (361 treated with bivalirudin and 462 treated with UFH) were enrolled in the study. GPIs, novel P2Y. The treatment of bivalirudin showed better efficacy and safety as compared to UFH among patients with ACS undergoing PCI at high risk of bleeding in contemporary practice.

Topics: Acute Coronary Syndrome; Anticoagulants; Disease Management; Hemorrhage; Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Practice Patterns, Physicians'; Recombinant Proteins; Risk Assessment; Risk Factors; Thrombosis; Treatment Outcome

Bivalirudin is associated with an increased risk of acute stent thrombosis (AST) compared to unfractionated heparin (UFH) in acute coronary syndrome patients (ACS) during short-duration percutaneous coronary intervention (PCI). The mechanisms involved are unknown. We aimed to investigate the antithrombotic efficacy of bivalirudin compared to UFH during PCI. In a monocenter study, we prospectively enrolled 30 patients undergoing PCI for a non-ST elevation ACS. They were randomly assigned to a single intravenous (IV) bolus of UFH (70 IU/kg) or an IV bolus of bivalirudin 0.75 mg/kg followed by a 1.75 mg/kg/h infusion during PCI. All patients received a loading dose (LD) of 180 mg of ticagrelor at the time of PCI. The VASP index and activated partial thromboplastin time (aPTT) were used to assess the course of platelet reactivity (PR) and antithrombotic activity. The two groups were similar regarding baseline, angiographic, and interventional characteristics. There was no difference between the two groups in the course of PR following ticagrelor LD. An optimal PR inhibition was obtained 4 h after the LD of ticagrelor. The level of antithrombotic activity was significantly lower in the bivalirudin group compared to the UFH group (p < 0.001) during PCI but similar at 2 and 4 h post-PCI. We observed that, in ACS undergoing PCI, the antithrombotic efficacy of an IV bolus of bivalirudin is significantly lower than that of a 70-IU/kg UFH bolus. This could contribute to the excess in thrombotic acute events observed during short-duration PCI.

Topics: Acute Coronary Syndrome; Aged; Blood Coagulation; Blood Platelets; Female; Fibrinolytic Agents; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Aggregation; Recombinant Proteins; Risk Factors; Thrombosis

To compare prolonged bivalirudin infusion vs. an intra-procedural only bivalirudin infusion administration in subjects with ST-segment elevation myocardial infarction (STEMI) regarding residual stent strut thrombosis.. Multivessel STEMI patients undergoing primary percutaneous coronary intervention (PPCI) and scheduled for a staged percutaneous coronary intervention (PCI) before hospital discharge were selected among those allocated to either prolonged bivalirudin or intra-procedural only bivalirudin infusion in the MATRIX (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and angioX) Treatment-Duration study. Optical coherence tomography (OCT) of the infarct-related artery was performed at the end of PPCI and 4-5 days thereafter during staged intervention. The predefined endpoint was the percentage difference in the number of stent cross-sections with a thrombotic area >5% at the end of PPCI and at the time of staged PCI (ΔThCS). Between September 2013 and November 2015, 137 were randomized to either intra-procedural only bivalirudin infusion (N = 64) or prolonged bivalirudin (N = 73) at 16 European sites. Mean stent area, minimum lumen area, percentage of malapposed struts, and mean percent thrombotic area were comparable after index or staged PCI. The difference in the proportion of frames with percent thrombotic area >5% (ΔTh > 5%) were -7.7 (-22.1 to 5.1) in the intra-procedural bivalirudin infusion group and -8.8 (-23.1 to 2.6) in the prolonged infusion group (P = 0.994). Time from index to follow-up OCT imaging and the infarct vessel artery did not affect this OCT-based endpoint.. A strategy of prolonged bivalirudin infusion after PPCI did not reduce residual stent strut thrombosis when compared with intra-procedural only bivalirudin infusion administration (funded by The Medicines Company and Terumo; MATRIX ClinicalTrials.gov number, NCT01433627).

Topics: Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; ST Elevation Myocardial Infarction; Stents; Thrombosis; Tomography, Optical Coherence; Treatment Outcome

Topics: Heparin; Hirudins; Humans; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; ST Elevation Myocardial Infarction; Stents; Thrombosis; Treatment Outcome

Pump thrombosis remains a serious complication of implantable ventricular assist device therapy and is associated with increased risk of morbidity and mortality. Optimal management strategies remain controversial and are guided largely by limited literature and expert opinion. Medical management of pump thrombosis, including the use of direct thrombin inhibitors, has been associated with mixed results. The purpose of this study is to report the outcomes associated with bivalirudin therapy in LVAD patients with suspected pump thrombosis. A single-center, retrospective observational study of 15 patients with suspected pump thrombosis that were all treated with bivalirudin therapy was conducted. The majority of subjects' initial treatment courses were unsuccessful [9/15 (60%)]; however, 6/15 (40%) achieved an initial improvement in serum lactate dehydrogenase (LDH) levels and were stabilized to be successfully discharged from the hospital. Of the subjects discharged, there was a high rate of recurrence of pump thrombosis within 6 months [5/6 (83.3%)]. Bivalirudin therapy was not associated with a consistent reduction in LDH among all subjects studied, and clinical responses to therapy appear to be associated with high rates of thrombosis recurrence. This study analyzes the largest cohort to date of LVAD patients with pump thrombosis treated with bivalirudin therapy, and suggests that alternative therapies should be considered in management.

Topics: Adult; Aged; Heart Ventricles; Heart-Assist Devices; Hirudins; Humans; L-Lactate Dehydrogenase; Middle Aged; Peptide Fragments; Recombinant Proteins; Recurrence; Retrospective Studies; Thrombosis; Treatment Outcome

Thrombotic complications are increasing at a steady and significant rate in children resulting in the more widespread use of anticoagulation in this population. Anticoagulant drugs in children can be divided into the standard agents (heparin, low molecular weight heparin, and vitamin K antagonists) and alternative agents (argatroban, bivalirudin, and fondaparinux). This review will compare and contrast the standard and alternative anticoagulants and suggest situations in which it may be appropriate to use argatroban, bivalirudin, and fondaparinux. Clearly, the standard anticoagulants all have significant shortcomings including variable pharmacokinetics, issues with therapeutic drug monitoring, frequency of administration, efficacy, and adverse effects. The alternative anticoagulants have properties which overcome these shortcomings and prospective clinical trial data are presented supporting the current and future use of these agents in place of the standard anticoagulants.

Topics: Anticoagulants; Arginine; Blood Coagulation; Child; Drug Monitoring; Fondaparinux; Heparin; Hirudins; Humans; Peptide Fragments; Pipecolic Acids; Polysaccharides; Recombinant Proteins; Sulfonamides; Thrombosis; Venous Thromboembolism; Warfarin

Topics: Anticoagulants; Antithrombins; Blood Coagulation Tests; Cardiomyopathies; Cardiopulmonary Bypass; Disease Management; Female; Fibrinolytic Agents; Heart Transplantation; Heparin; Hirudins; Humans; Kidney Transplantation; Middle Aged; Peptide Fragments; Recombinant Proteins; Renal Insufficiency, Chronic; Thrombocytopenia; Thrombosis

Heparin-induced thrombocytopenia (HIT) results in platelet consumption and a virulent thrombotic state, which generally responds to cessation of heparin and initiation of anticoagulation. Rarely, delayed HIT can occur and/or persist after heparin is discontinued.. A 47-year-old male developed delayed HIT with severe thrombocytopenia and thrombosis after cardiac surgery. Thrombocytopenia developed and persisted after heparin cessation and did not improve despite sequential use of argatroban followed by bivalirudin. Treatment with intravenous immunoglobulin (IVIg) was well tolerated and resulted in rapid resolution of thrombocytopenia.. There are few case reports on the management of delayed HIT with severe and prolonged thrombocytopenia. The risk for thrombosis and bleeding in the setting of an undefined time course increases uncertainty in management.. This case, along with others accumulating in the literature, suggest that IVIg may be effective in treating delayed HIT with persistent thrombocytopenia.

Topics: Arginine; Cardiac Surgical Procedures; Heparin; Hirudins; Humans; Immunoglobulins, Intravenous; Male; Middle Aged; Peptide Fragments; Pipecolic Acids; Postoperative Complications; Recombinant Proteins; Sulfonamides; Thrombocytopenia; Thrombosis

Dialysis patients are at a higher risk of bleeding after percutaneous coronary intervention (PCI); however, due to their exclusion from randomized clinical trials, the optimal antithrombotic regimen for this population remains unknown. We sought to evaluate the comparative safety and effectiveness of bivalirudin monotherapy versus unfractionated heparin (UFH) monotherapy in dialysis patients undergoing PCI.. We included dialysis patients who underwent PCI in a multicenter registry between January 2010 and September 2015 at 47 Michigan hospitals. We compared in-hospital outcomes between bivalirudin versus UFH; excluding those treated with glycoprotein IIb/IIIa inhibitors. Optimal full matching was used to account for the nonrandom use of these drugs.. Of 177,963 patients who underwent PCI, 4,303 (2.4%) were on dialysis. Among those, 1,257 (29.2%) received bivalirudin monotherapy and 2,112 (49.1%) received UFH monotherapy. Patients treated with bivalirudin had fewer comorbidities. After matching, there were no significant differences in outcomes between those who received bivalirudin versus UFH: bleeding (adjusted odds ratio: 0.67; 95% confidence interval: 0.41-1.07; P = 0.093); major bleeding (0.81; 0.19-3.50; P = 0.77); transfusion (1.01; 0.77-1.33; P = 0.96); repeat PCI (0.57; 0.14-2.24; P = 0.42); stent thrombosis (0.56; 0.05-5.83; P = 0.63); and death (0.84; 0.46-1.51; P = 0.55).. We found no significant differences in in-hospital outcomes between bivalirudin and UFH monotherapy among dialysis patients undergoing PCI. Randomized clinical trials are needed to determine the optimal anticoagulant regimen for this population. © 2017 Wiley Periodicals, Inc.

Topics: Aged; Anticoagulants; Antithrombins; Blue Cross Blue Shield Insurance Plans; Comparative Effectiveness Research; Coronary Artery Disease; Female; Hemorrhage; Heparin; Hirudins; Humans; Logistic Models; Male; Michigan; Middle Aged; Odds Ratio; Peptide Fragments; Percutaneous Coronary Intervention; Propensity Score; Recombinant Proteins; Registries; Renal Dialysis; Renal Insufficiency, Chronic; Retrospective Studies; Risk Factors; Stents; Thrombosis; Time Factors; Treatment Outcome

Heparin-induced thrombocytopenia (HIT) is an uncommon problem in hemodialysis (HD) patients. There have been a few reports on the use of lepirudin, argatroban, or danaparoid in the management of extracorporeal thrombosis (ECT) during dialysis in these patients, because heparin is contraindicated. Here, we report the first long-term use of bivalirudin to prevent ECT. Our study was conducted at Fahd Bin Jassim Kidney Center in Doha, Qatar. All patients diagnosed with HIT were included. A bivalirudin treatment protocol was developed with the initial dosage and dosage adjustments based on the value of activated partial thromboplastin time (aPTT), the risk of bleeding, and the recurrence of ECT. Eight patients were positive for HIT AB. Among them, three were excluded: two due to the use of warfarin for atrial fibrillation and one due to a negative repeat HIT AB test with no ECT. Five patients who were positive for HIT AB and experienced recurrent ECT events during dialysis were included. These patients were monitored while on bivalirudin protocol for a mean of 4.6 ± 2 months, during which they received a mean number of HD treatments of 66 ± 24. There were no bleeding events or adverse reactions related to bivalirudin during the study. Here, we report the first long-term successful use of a bivalirudin protocol to prevent ECT in ambulatory HD patients with HIT. This protocol allowed for a simple dosing initiation with easy adjustment based on weight, aPTT, and recurrence of ECT events. The protocol provided excellent safety.

Topics: Adult; Aged; Antithrombins; Clinical Protocols; Female; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Renal Dialysis; Thrombocytopenia; Thrombosis

Prolonging infusions may abrogate the acute stent thrombosis (ST) associated with bivalirudin use during primary PCI but at an increased cost. We hypothesized that continuing the bivalirudin infusion commenced during the procedure at the PCI recommended dose until infusion end would prevent excess early ST.. Baseline demographics, procedural data and outcomes were gathered prospectively on 1395 consecutive patients undergoing primary PCI. The choice of bivalirudin versus heparin was at the cardiologist's discretion. Local protocol recommended continuation of the procedural bivalirudin at the PCI dose until infusion end.. Patients' mean age was 62.8 ± 13.1years with 11.4% presenting with shock. The majority of patients underwent PCI using bivalirudin with fewer using heparin (87.7 vs. 12.3%, P < 0.0001). Glycoprotein inhibitor bailout rates were 6.1% with bivalirudin and 36.3% with heparin (P < 0.0001). Calculated on an individual patient basis the median intra-procedure duration of the bivalirudin infusion was 30(IQR 21-43) minutes and post-procedure 49(32-66) minutes. The acute (<24-hours) ST rates were 4/1224 with bivalirudin ± GPI (0.3%) and 0/171 with heparin ± GPI (0%, P = 0.41). The sub-acute (24-hours to 30-days) ST rates were 3/1224 for bivalirudin ± GPI (0.3%) and 2/171 with heparin ± GPI (1.2%, P = 0.11). In total the early (<30-days) ST rates were 7/1224 for bivalirudin ± GPI (0.6%) and 2/171 with heparin ± GPI (1.2%, P = 0.31). Acute ST was significantly more likely to occur in clopidogrel-loaded patients than prasugrel/ticagrelor patients (2.7 vs. 0.5%, P = 0.003).. Continuing the bivalirudin infusion commenced during the procedure at the PCI recommended dose until infusion end combined with potent P2 Y12 inhibitors ameliorates excess early stent thrombosis.

Topics: Aged; Aged, 80 and over; Antithrombins; Female; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; Stents; Survival Rate; Thrombosis

We aimed to assess the association of bivalirudin with post-procedural Thrombolysis In Myocardial Infarction (TIMI) flow, acute (≤24 hours) and 30-day stent thrombosis (ST), and one-year mortality.. The study included 11,623 patients undergoing percutaneous coronary intervention (PCI). The primary outcomes were post-procedural TIMI flow grade ≤2 and definite acute ST. In groups treated with bivalirudin (n=3,135), abciximab plus unfractionated heparin (UFH; n=3,539) and UFH alone (n=4,949), post-procedural TIMI was ≤2 in 5.2%, 3.2% and 3.2% of patients, respectively (adjusted odds ratio [OR]=1.96 [95% confidence interval] 1.47-2.56 for bivalirudin versus abciximab plus UFH and OR=1.56 [1.20-2.04] for bivalirudin versus UFH). Definite acute ST occurred in two patients (0.06%) treated with bivalirudin, two patients (0.06%) treated with abciximab plus UFH, and seven patients (0.14%) treated with UFH (p=0.47). Bivalirudin was not associated with increased risk of 30-day ST (hazard ratio [HR]=1.20 [0.59-2.43] versus abciximab plus UHF, and HR=0.93 [0.48-1.82] versus UFH) or one-year mortality (HR=0.95 [0.70-1.28] versus abciximab plus UHF, and HR=1.05 [0.78-1.41] versus UFH).. Bivalirudin was associated with higher risk of suboptimal post-PCI TIMI flow but not with increased risk of acute or 30-day definite ST or one-year mortality compared with abciximab plus UFH or UFH alone.

Topics: Abciximab; Aged; Antibodies, Monoclonal; Anticoagulants; Antithrombins; Female; Heparin; Hirudins; Humans; Immunoglobulin Fab Fragments; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Recombinant Proteins; Risk; Stents; Thrombosis

The direct thrombin inhibitor bivalirudin is an option for anticoagulation in patients with heparin induced thrombocytopenia (HIT) requiring cardiopulmonary bypass (CPB). There are a limited number of reports of pediatric patients in which bivalirudin has been used for anticoagulation for CPB. We present the case of an 11 year old male with acute onset heart failure secondary to idiopathic dilated cardiomyopathy that developed heparin induced thrombocytopenia with thrombosis (HITT). The patient was anticoagulated in the operating room with bivalirudin and placed on CPB for insertion of a HeartWare(®) Ventricular Assist Device (Heartware(®)). Modified techniques were utilized. This included use of the Terumo CDI 500 (Terumo Cardiovascular Systems, Inc.) in-line blood gas monitor which contains a heparin coated arterial shunt sensor. We flushed this sensor with buffered saline preoperatively and noted no significant decrease in platelet count postoperatively. The patient was successfully placed on the ventricular assist device and was subsequently listed for heart transplantation.

Topics: Anticoagulants; Cardiomyopathy, Dilated; Cardiopulmonary Bypass; Child; Heart Failure; Heart Transplantation; Heart-Assist Devices; Heparin; Hirudins; Humans; Male; Peptide Fragments; Recombinant Proteins; Thrombocytopenia; Thrombosis

Intracoronary thrombus is a common finding in acute coronary syndromes and often correlates with adverse prognosis and complications during percutaneous coronary interventions (PCIs). Bivalirudin, a direct thrombin inhibitor, is one of the recommended antithrombotic treatments for PCI in ST-elevation myocardial infarction (STEMI). The intracoronary administration of a bivalirudin loading dose, even if off-label, offers theoretical advantages over the standard intravenous route, providing a very high drug concentration in the infarct-related artery without increasing the total dose of the drug administered. After the description in case reports of such an approach, a larger scale experience was recently reported in a large cohort of patients with STEMI treated during primary PCI with a bivalirudin intracoronary loading dose followed by the standard intravenous maintenance infusion. As a control group, a propensity score-matched cohort of patients undergoing primary PCI treated with intravenous bivalirudin in the same institution was selected. Compared with the intravenous bolus, the intracoronary administration of bivalirudin was associated with improved ST-segment resolution, lower post-procedural peak CK-MB levels, and better Thrombolysis in Myocardial Infarction (TIMI) frame count values, without difference in bleeding rates. Thus, this new promising antithrombotic strategy, based on the intracoronary administration of a bivalirudin loading dose during primary PCI, appeared safe, improved myocardial reperfusion, and mitigated enzymatic myocardial infarct size compared with the standard intravenous protocol. Randomized trials are warranted to confirm these results and evaluate the possible long-term clinical benefits.

Topics: Angioplasty, Balloon, Coronary; Anticoagulants; Antithrombins; Electrocardiography; Hemorrhage; Hirudins; Humans; Injections, Intravenous; Myocardial Infarction; Myocardial Reperfusion; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Recombinant Proteins; Thrombosis

Bivalirudin is a direct thrombin inhibitor used in the cardiac intensive care unit when heparin is contraindicated due to heparin-induced thrombocytopenia. Since it is not a commonly used drug, clinical experience with its dosing is sparse. In earlier work [1], we developed a dynamic system model that accurately predicts the effect of bivalirudin given dosage over time and patient physiological characteristics. This paper develops adaptive dosage controllers that regulate its effect to desired levels. To that end, and in the case that bivalirudin model parameters are available, we develop a Model Reference Control law. In the case that model parameters are unknown, an indirect Model Reference Adaptive Control scheme is applied to estimate model parameters first and then adapt the controller. Alternatively, direct Model Reference Adaptive Control is applied to adapt the controller directly without estimating model parameters first. Our algorithms are validated using actual patient data from a large hospital in the Boston area.

Topics: Antithrombins; Computer Simulation; Drug Monitoring; Drug Therapy, Computer-Assisted; Feedback, Physiological; Hirudins; Humans; Infusions, Intravenous; Intensive Care Units; Models, Cardiovascular; Peptide Fragments; Recombinant Proteins; Thrombosis

A pediatric patient requiring venovenous (VV) extracorporeal membrane oxygenation (ECMO) as a bridge to lung transplantation developed heparin-induced thrombocytopenia. Unfractionated heparin was discontinued, and a bivalirudin infusion was started. During the lung transplant evaluation, he was found to have allosensitization, requiring treatment with plasma exchange along with pulse methylprednisolone, rituximab, bortezomib, and pooled immunoglobulin infusion. We describe our experience with successful plasma exchange for allosensitization during bivalirudin anticoagulation on VV ECMO in a pediatric patient.

Topics: Antithrombins; Extracorporeal Membrane Oxygenation; Fatal Outcome; Heparin; Hirudins; Humans; Infant; Lung Transplantation; Male; Peptide Fragments; Plasma Exchange; Preoperative Care; Recombinant Proteins; Thrombocytopenia; Thrombosis

A 74-year-old female had urgent surgery with replacement of the ascending aorta for acute type A dissection. Postprocedure, the electrocardiogram showed an ST-segment elevation myocardial infarction in the antero-lateral leads. Angiography revealed a thrombotic occlusion of the left anterior descending artery, treated successfully with bivalirudin administration, thrombus aspiration and a balloon angioplasty. This case involves the rare coexistence of acute type A aortic dissection and myocardial infarction due to coronary plaque thrombosis.

Topics: Acute Disease; Aged; Angioplasty, Balloon, Coronary; Aorta; Aortic Aneurysm; Aortic Dissection; Coronary Angiography; Coronary Vessels; Electrocardiography; Female; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Recombinant Proteins; Thrombectomy; Thrombosis; Treatment Outcome

Bivalirudin and heparin are the major available parenteral anticoagulants for percutaneous coronary intervention (PCI) in ST-segment-elevation myocardial infarction. Even though hard clinical outcomes are comparable with both drugs, bivalirudin appears to be safer (less bleeding events) at the expense of lower short-term efficacy (more acute stent thrombosis events). The selection of anticoagulation during PCI in ST-segment-elevation myocardial infarction should be individualized, taking into account the patient's ischemic and bleeding risk. In patients with increased bleeding risk, bivalirudin might be preferable to heparin, whereas in complex PCI with increased risk for stent thrombosis, heparin is preferable. Further clinical studies are needed to elucidate the role of these drugs in PCI for ST-segment-elevation myocardial infarction in the era of radial approaches, new potent antiplatelet agents and the use of glycoprotein IIb/IIIa inhibitors.

Topics: Administration, Intravenous; Antithrombins; Electrocardiography; Hemorrhage; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; Risk Assessment; Stents; Thrombosis

We aimed to compare safety and efficacy of the direct thrombin inhibitor bivalirudin with unfractionated heparin (UFH) during transcatheter aortic valve implantation (TAVI).. In this retrospective analysis, 461 patients underwent TAVI between 2007 and 2012; 339 patients received bivalirudin, and 122 patients received UFH. In the bivalirudin group, the Sapien XT valve was implanted in 159 (46.9%) patients, and 180 (53.1%) received a Medtronic CoreValve. In the UFH group, only the Medtronic CoreValve was implanted. The primary outcome of interest was the incidence of any bleeding. Secondary outcomes of interest were all-cause mortality and cardiovascular mortality at 72 hours after the procedure and at 30 days.. No significant difference between the groups was observed for life-threatening bleeding (2.4% for bivalirudin vs 3.3% for UFH; P = 0.59), major bleeding (8.3% vs 8.2%, respectively; P = 0.98) and minor bleeding (8.3% vs 7.4%, respectively; P = 0.76). At 72 hours after the procedure, all-cause mortality was 3.0% in the bivalirudin group and 3.3% for the UFH group (P = 0.88), whereas cardiovascular mortality was 3.0% in the bivalirudin group and 2.5% in the heparin group (P = 0.77). At 30 days, all-cause mortality was 5.3% vs 4.1% in the bivalirudin and heparin groups (P = 0.57) and cardiovascular mortality was 4.4% vs 2.5% (P = 0.33). Device success (Valve Academic Research Consortium 2 composite end point) was 94.0% in the bivalirudin-treated and 92.6% in the UFH-treated patients (P = 0.60). The early safety at 30 days was 85.3% in the bivalirudin-treated group compared with 83.6% in the UFH-treated group (P = 0.65).. Bivalirudin has a safety and efficacy profile similar to weight-adjusted UFH during the TAVI procedure.

Topics: Aged, 80 and over; Anticoagulants; Antithrombins; Aortic Valve Stenosis; Female; Follow-Up Studies; Heparin; Hirudins; Humans; Male; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombosis; Transcatheter Aortic Valve Replacement; Treatment Outcome

Anticoagulation with unfractionated heparin (UFH) in critically ill cardiac surgery patients has several limitations, including the risk of heparin-induced thrombocytopenia. The use of a direct thrombin inhibitor, such as bivalirudin, might either treat this complication or completely eliminate it. The aim of the present study was to analyze the use of bivalirudin in this setting, as either a secondary drug switching from heparin or as the primary anticoagulant, and to evaluate clinical outcomes.. Propensity-matching retrospective analysis.. A cardiac surgery intensive care unit.. One hundred propensity-matched patients who received heparin or bivalirudin.. Bivalirudin was administered as a first-line or second-line drug after heparin discontinuation in case of thrombocytopenia and suspicion of heparin-induced thrombocytopenia. Twenty-six patients (52%) received bivalirudin as a primary anticoagulant, while 24 patients (48%) received bivalirudin after switching from heparin.. Bivalirudin treatment was associated with a reduction of major bleeding (p=0.05) compared with the control group. Interestingly, in an intention-to-treat analysis, patients receiving primary bivalirudin showed significant reductions in minor bleeding (p=0.04), and mortality (p=0.01) compared with the secondary bivalirudin group and, similarly, compared with the rest of the study population (UFH and secondary bivalirudin patients, p=0.01 and p=0.05, respectively). Predictors of hospital mortality by multivariate analysis included urgent admission (odds ratio [OR]=2.7; 95 confidence interval [CI], 1.03-7.2; p=0.04), ;septic shock (OR=8.0; 95 CI, 2.26-28.7; p<0.005) and primary therapy with UFH (OR=19.2; 95 CI, 2.2-163.9; p=0.007).. Novel anticoagulant strategies might play a crucial role in critically ill cardiac surgery patients. In a propensity-matched population, results of the present study showed that primary bivalirudin anticoagulation may reduce bleeding complications and mortality.

Topics: Antithrombins; Cardiac Surgical Procedures; Critical Illness; Dose-Response Relationship, Drug; Female; Follow-Up Studies; Hirudins; Humans; Injections, Intravenous; Italy; Male; Middle Aged; Peptide Fragments; Postoperative Complications; Propensity Score; Recombinant Proteins; Retrospective Studies; Survival Rate; Thrombosis

The use of bivalirudin versus unfractionated heparin monotherapy in patients without ST-segment-elevation myocardial infarction is not well defined.. The study population consisted of patients enrolled in the Evaluation of Drug-Eluting Stents and Ischemic Events (EVENT) registry with either non-ST-segment-elevation acute coronary syndromes or stable ischemic heart disease, who underwent percutaneous coronary intervention with either unfractionated heparin or bivalirudin monotherapy. Propensity score matching was used to adjust for baseline characteristics. The primary bleeding (in-hospital composite bleeding-access site bleeding, thrombolysis in myocardial infarction major/minor bleeding, or transfusion) and primary (in-hospital death/myocardial infarction) and secondary ischemic outcomes (death/myocardial infarction/unplanned repeat revascularization at 12 months) were evaluated. Propensity score matching yielded 1036 patients with non-ST-segment-elevation acute coronary syndromes and 2062 patients with stable ischemic heart disease. For the non-ST-segment-elevation acute coronary syndrome cohort, bivalirudin use was associated with lower bleeding (difference, -3.3% [-0.8% to -5.8%]; P=0.01; number need to treat=30) without increase in either primary (difference, 1.2% [4.1% to -1.8%]; P=0.45) or secondary ischemic outcomes, including stent thrombosis (difference, 0.0% [1.3% to -1.3%]; P=1.00). Similarly, in the stable ischemic heart disease cohort, bivalirudin use was associated with lower bleeding (difference, -1.8% [-0.4% to -3.3%]; P=0.01; number need to treat=53) without increase in either primary (difference, 0.4% [2.3% to -1.5%]; P=0.70) or secondary ischemic outcomes, including stent thrombosis (difference, 0.0% [0.7% to -0.7%]; P=1.00) when compared with unfractionated heparin monotherapy.. Among patients with non-ST-segment-elevation acute coronary syndromes or stable ischemic heart disease undergoing percutaneous coronary intervention, bivalirudin use during percutaneous coronary intervention when compared with unfractionated heparin monotherapy was associated with lower bleeding without significant increase in ischemic outcomes or stent thrombosis.

Topics: Acute Coronary Syndrome; Aged; Anticoagulants; Cohort Studies; Electrocardiography; Female; Follow-Up Studies; Hemorrhage; Heparin; Hirudins; Humans; Incidence; Male; Middle Aged; Myocardial Ischemia; Peptide Fragments; Percutaneous Coronary Intervention; Prospective Studies; Recombinant Proteins; Registries; Risk Factors; Thrombosis; Treatment Outcome

Optimal anticoagulation plays a pivotal role in successful outcome of extracorporeal membrane oxygenation (ECMO). Heparin has been the anticoagulant of choice owing to its advantages like easy monitoring and reversibility. However, if heparin resistance is encountered, one has to decide whether to treat heparin resistance with fresh-frozen plasma or antithrombin concentrates or to choose one of the heparin alternatives for anticoagulation. We report a case of heparin resistance resulting from antithrombin III deficiency in a patient on venovenous ECMO, in which anticoagulation was managed with bivalirudin. The dose of bivalirudin for anticoagulation in ECMO has not been standardized and different authors have reported different doses. We found a bivalirudin dose of .1-.2 mg/kg/h to be adequate to maintain a target activated clotting time of 200-220 seconds. Platelet counts were stable throughout and no major bleeding or thrombotic complications took place. We found bivalirudin to be a feasible and effective anticoagulant and safe to use for long durations in ECMO without any major complications.

Topics: Antithrombins; Extracorporeal Membrane Oxygenation; Hemofiltration; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Thrombocytopenia; Thrombosis; Treatment Outcome

Aptamers are nucleic acid based molecular recognition elements with a high potential for the theranostics. Some of the aptamers are under development for therapeutic applications as promising antithrombotic agents; and G-quadruplex DNA aptamers, which directly inhibit the thrombin activity, are among them. RA-36, the 31-meric DNA aptamer, consists of two thrombin binding pharmacophores joined with the thymine linker. It has been shown earlier that RA-36 directly inhibits thrombin in the reaction of fibrinogen hydrolysis, and also it inhibits plasma and blood coagulation. Studies of both inhibitory and anticoagulation effects had indicated rather high species specificity of the aptamer. Further R&D of RA-36 requires exploring its efficiency in vivo. Therefore the development of a robust and adequate animal model for effective physiological studies of aptamers is in high current demand. This work is devoted to in vivo study of the antithrombotic effect of RA-36 aptamer. A murine model of thrombosis has been applied to reveal a lag and even prevention of thrombus formation when RA-36 was intravenous bolus injected in high doses of 1.4-7.1 µmol/kg (14-70 mg/kg). A comparative study of RA-36 aptamer and bivalirudin reveals that both direct thrombin inhibitors have similar antithrombotic effects for the murine model of thrombosis; though in vitro bivalirudin has anticoagulation activity several times higher compared to RA-36. The results indicate that both RA-36 aptamer and bivalirudin are direct thrombin inhibitors of different potency, but possible interactions of the thrombin-inhibitor complex with other components of blood coagulation cascade level the physiological effects for both inhibitors.

Topics: Animals; Anticoagulants; Antithrombins; Aptamers, Nucleotide; Blood Coagulation; Disease Models, Animal; Drug Evaluation, Preclinical; Fibrinogen; Fibrinolytic Agents; G-Quadruplexes; Hirudins; Male; Mice; Mice, Inbred C57BL; Peptide Fragments; Recombinant Proteins; Thrombin; Thrombosis

We report the case of a 27-year-old woman with signs of heparin-induced thrombocytopenia and thrombosis (HITT) and left heart failure presenting for urgent implantation of a left ventricular assist device (LVAD). HITT can occur in 4.2-6.1% of patients with LVADs. If the patient remains hemodynamically stable, implantation can be delayed for several months until the heparin/PF-4 antibodies decline allowing the use of heparin on cardiopulmonary bypass, However, in most cases related to cardiogenic shock, surgery cannot be delayed. We present the case of a patient who underwent implantation of a HeartMate II LVAD and discuss management strategy using bivalirudin during cardiopulmonary bypass.

Topics: Adult; Anticoagulants; Antithrombins; Cardiopulmonary Bypass; Combined Modality Therapy; Female; Heart Diseases; Heart Ventricles; Heart-Assist Devices; Heparin; Hirudins; Humans; Peptide Fragments; Prosthesis Implantation; Recombinant Proteins; Thrombocytopenia; Thrombosis; Treatment Outcome

Heparin-induced thrombocytopenia presents a challenge for anticoagulation techniques during cardiac surgery and ventricular assist device implantation. Bivalirudin is currently recommended for use during cardiopulmonary bypass for patients with heparin-induced thrombocytopenia but requires the use of special techniques to avoid blood stagnation. We report the successful use of bivalirudin during cardiopulmonary bypass for implantation of the Total Artificial Heart with late operative bleeding likely resulting from heavy cell saver use.

Topics: Adult; Antithrombins; Cardiopulmonary Bypass; Heart, Artificial; Hirudins; Humans; Male; Peptide Fragments; Premedication; Prosthesis Implantation; Recombinant Proteins; Thrombosis; Treatment Outcome

Application of anticoagulants remains the primary strategy for prevention and treatment of thrombosis. However, high rate of bleeding complications limits their use. The peptide anticoagulant bivalirudin has been reported to exhibit a lower rate of bleeding complications than heparin, and it also has the advantage of not causing thrombocytopenia, which is a problem with heparin. Nonetheless, hemorrhage is the most common complication of bivalirudin therapy, and there is no effective antidote. Here we use a thrombus-binding peptide, CR(NMe)EKA, to accomplish selective delivery of the bivalirudin-carrying micellar nanocarrier to sites of thrombosis. Bivalirudin and CR(NMe)EKA, each with a PEG-lipid tail, spontaneously assembled into 30 nm micelles, which almost completely retained the anticoagulant activity of bivalirudin. The micellar formulations exhibited high stability both in vitro and in vivo. In a thromboplastin-induced mouse thrombosis model, the targeted micelles accumulated in lung thrombi 10-fold more than nontargeted micelles. Moreover, the micellar formulation significantly prolonged the half-life and thereby increased the bioavailability of bivalirudin. The micellar bivalirudin had significantly higher anticoagulant activity than free bivalirudin in both the lung thrombosis model and a ferric chloride-induced carotid artery thrombosis model. The specific targeting of thrombi demonstrated here makes it possible to increase the efficacy of bivalirudin as an anticoagulant. Alternatively, the dose could be reduced without loss of efficacy to lower the systemic exposure and improve safety.

Topics: Animals; Anticoagulants; Half-Life; Hirudins; Mice; Mice, Inbred C57BL; Micelles; Peptide Fragments; Recombinant Proteins; Thrombosis

After on-pump coronary artery bypass graft surgery, a patient had acute heparin-induced thrombocytopenia with thoracic arterial and venous thrombus formations. Complex emergency surgery with cardiopulmonary bypass and deep hypothermic circulatory arrest using bivalirudin anticoagulation was performed.

Topics: Aged; Anticoagulants; Antithrombins; Blood Coagulation; Cardiopulmonary Bypass; Circulatory Arrest, Deep Hypothermia Induced; Coronary Artery Bypass; Coronary Artery Disease; Dose-Response Relationship, Drug; Heparin; Hirudins; Humans; Male; Peptide Fragments; Recombinant Proteins; Thrombectomy; Thrombocytopenia; Thrombosis

Here we present our attempt at off pump HeartMate II left ventricular assist device (LVAD) implantation using the anticoagulant bivalirudin in a patient with heparin induced thrombocytopenia, which resulted in thrombosis within the LVAD device. This required that our procedure be converted to on pump, and a new HeartMate II LVAD device to be implanted. In our view, this thrombotic event may have been caused by a number of factors that include bivalirudin's (1) short half-life of about 20 minutes, (2) decreased activity with blood stasis, (3) inability to prevent clot propagation, and (4) uncertainty with real-time monitoring of therapeutic levels. To prevent future thrombotic events, it may be beneficial to immediately deair the LVAD device prior to the coring of the left ventricle during off pump LVAD placement. In addition, a solution other than blood may be used for priming. If blood is used for priming of the LVAD device, the duration of blood stasis should not exceed 20 minutes when bivalirudin is being used for anticoagulation. Furthermore, this case emphasizes the importance of having a backup LVAD device available and ready to use during surgical procedures.

Topics: Aged; Anticoagulants; Antithrombins; Blood Coagulation; Female; Heart Ventricles; Heart-Assist Devices; Heparin; Hirudins; Humans; Peptide Fragments; Recombinant Proteins; Thoracic Surgical Procedures; Thrombocytopenia; Thrombosis

In patients with acute heparin-induced thrombocytopenia (HIT) needing urgent cardiac surgery, bivalirudin is recommended as a first-line strategy for intraoperative anticoagulation. However, due to the unique elimination process of bivalirudin, careful adjustment of the perfusion and surgical strategy is mandatory as blood stasis in the circuit or prolonged interruption of areas or compartments containing blood from the systemic circulation may result in thrombus formation. We report here a modified surgical strategy for the implantation of the HeartWare™ left ventricular assist device, which avoids prolonged disconnection of the blood-filled device from the systemic blood flow, so that bivalirudin can be safely used as anticoagulant.

Topics: Anticoagulants; Blood Coagulation; Heart Failure; Heart-Assist Devices; Heparin; Hirudins; Humans; Peptide Fragments; Prosthesis Design; Prosthesis Implantation; Recombinant Proteins; Thrombocytopenia; Thrombosis; Treatment Outcome; Ventricular Function, Left

Bivalirudin has emerged as a suitable alternative anticoagulant to unfractionated heparin and low-molecular-weight heparins during percutaneous coronary intervention (PCI) procedures in the management of coronary artery disease and acute coronary syndromes (ACS). In clinical trials, bivalirudin dosing was standardized, and activated clotting time (ACT) did not influence dosing adjustments. The role of ACT monitoring of bivalirudin in PCI is not defined based on current practice guidelines.. The hypothesis of this study is that hyper- and hypo-ACT responses to bivalirudin in PCI may be associated with excessive bleeding or thrombotic complications.. The planned protocol screened all patients who received bivalirudin therapy and ACT monitoring during PCI in a single center's cardiac catheterization laboratory from July 2009 to June 2010. The first ACT monitored 5 to 60 minutes after bivalirudin initiation was screened for inclusion. Values above 800 seconds and below 300 seconds were included as hyper- and hypo-ACT responses, respectively. Outcomes assessed include thrombotic and bleeding complications.. There were 32 patients identified as hyper-responders and 20 patients identified as hypo-responders. There were no significant thrombotic or bleeding complications in the hyper-responder group. There was 1 case (1/20, 5%) of angiographically confirmed acute stent thrombosis immediately following the placement of 5 adjoining bare-metal stents in the right coronary artery of a hypo-responder.. Hyper-ACT responses to bivalirudin therapy in PCI were not associated with additional bleeding risk. Bivalirudin may not adequately protect hypo-ACT responders against thrombotic complications during PCI.

Topics: Acute Coronary Syndrome; Antithrombins; Blood Coagulation; Hemorrhage; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Percutaneous Coronary Intervention; Recombinant Proteins; Retrospective Studies; Risk Factors; Thrombosis; Time Factors; Whole Blood Coagulation Time

Anticoagulation with heparin is standard of care for patients maintained on extracorporeal life support. Very limited evidence exists for the use of alternative anticoagulants during extracorporeal life support. Patients with heparin-induced thrombocytopenia, heparin resistance, and evidence of significant thrombosis while on heparin may be candidates for alternative anticoagulation. The objective of this analysis is to present evidence for the use of bivalirudin during extracorporeal life support in pediatric patients.. Case series.. University of California, Davis Medical Center.. Twelve critically ill, pediatric patients receiving bivalirudin for anticoagulation during extracorporeal life support.. None.. Twelve patients meeting entry criteria received bivalirudin during the study period. The median patient age was 8 days (range, 1 d to 6 yr). Eight patients were neonates. Eight patients were male. Nine patients were supported with venoarterial extracorporeal life support. Median duration of extracorporeal life support was 226 hours (range, 111-913) and median time on bivalirudin was 92 hours (range, 60-230). Bivalirudin bolus doses were administered to select patients without bleeding complications. The maintenance dose that corresponded with initial target activated partial thromboplastin time ranged from 0.045 to 0.48 mg/kg/hr with a median rate of 0.16 mg/kg/hr. The median dose for days 1, 3, and 5 was 0.135, 0.175, and 0.267 mg/kg/hr, respectively. The correlation (r2) between dose adjustment and activated partial thromboplastin time response was 0.264.. This is the largest case series describing the use of a direct thrombin inhibitor in pediatric extracorporeal life support patients. The maintenance dose range reflected considerable inter-patient variability. There was an observed increase in dose requirements with time. Bivalirudin, with close monitoring, is a potential option for pediatric patients on extracorporeal life support who have developed heparin-induced thrombocytopenia, heparin resistance, or significant thrombosis while on heparin.

Topics: Antithrombins; Child; Child, Preschool; Drug Monitoring; Extracorporeal Membrane Oxygenation; Female; Hirudins; Humans; Infant; Infant, Newborn; Life Support Care; Male; Partial Thromboplastin Time; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombosis; Time Factors

Intracoronary thrombi are a common finding in the setting of acute coronary syndromes and correlate with intraprocedural complications, adverse prognosis and unpredictable response to standard pharmacological and interventional treatment. Interventional cardiologists have learned to fear the so-called hostile thrombus, with its aggressive and unstable behavior often leading to abrupt and refractory vessel closure. Here we report a case series of intracoronary bivalirudin administration to treat massive intracoronary thrombi, leading to rapid clot disappearance and coronary blood flow restoration. Interventional cardiologists might consider intracoronary bivalirudin administration as a bailout strategy during unusual critical situations.

Topics: Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Antithrombins; Coronary Angiography; Female; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Thrombosis

A 68-year-old male was admitted for implantation of an implantable cardioverter defibrillator (ICD). He had a prosthetic mechanical valve for which he was receiving anticoagulation with warfarin, but had developed an allergy to heparin. Therefore, we decided to use bivalirudin for anticoagulation, which permitted him to undergo the procedure without complications.

Topics: Aged; Anticoagulants; Cardiopulmonary Bypass; Defibrillators, Implantable; Drug Hypersensitivity; Fibrinolytic Agents; Heart Valve Prosthesis; Heparin; Hirudins; Humans; Male; Mitral Valve; Peptide Fragments; Prosthesis Implantation; Recombinant Proteins; Thrombosis; Warfarin

In primary angioplasty, bivalirudin is superior to treatment with heparin plus glycoprotein inhibitors for reducing cardiovascular events, although bivalirudin increases the risk of stent thrombosis. Our hypothesis is that the use of prasugrel plus bivalirudin in primary angioplasty would reduce stent thrombosis and cardiovascular events.. Consecutive patients with acute ST-segment elevation myocardial infarction who were treated by primary angioplasty within 12 hours of the onset of symptoms received bivalirudin plus clopidogrel (Group A) or bivalirudin plus prasugrel (Group B). We compared the groups using propensity score matching. The combined end-point was cardiac death, thrombosis, acute myocardial infarction, and cerebrovascular accident at 30 days.. We assessed 168 patients. The approach was preferentially radial (95.7%). No differences in baseline characteristics were observed between Groups A (n = 70) and B (n = 70). The total mortality and rate of major bleeding complications at 30 days were 0% for both of the groups. The rate of acute and subacute thrombosis was 4.3% in Group A and 0% in Group B (P = 0.08). We observed an increased rate of events in Group A (5.7%) versus Group B (0%) (P = 0.042).. The administration of bivalirudin plus prasugrel in primary percutaneous coronary intervention reduces cardiovascular effects compared to bivalirudin plus clopidogrel without increasing major bleeding complications during the first 30 days following primary angioplasty performed with a preferentially radial approach.

Topics: Angioplasty; Antithrombins; Clopidogrel; Cohort Studies; Drug Combinations; Female; Hirudins; Humans; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Piperazines; Postoperative Complications; Prasugrel Hydrochloride; Recombinant Proteins; Retrospective Studies; Thiophenes; Thrombosis; Ticlopidine

Reocclusion is one of the major root causes for secondary complications that arise during thrombolytic therapy. A multifunctional staphylokinase variant SRH (staphylokinase (SAK) linked with tripeptide RGD and didecapeptide Hirulog) with antiplatelet and antithrombin activities in addition to clot specific thrombolytic function, was developed to address the reocclusion problem. We preferred to use Escherichia coli GJ1158 as the host in this study for economic production of SRH by osmotic (0.3 mol/L sodium chloride) induction, to overcome the problems associated with the yeast expression system. The therapeutic potential of SRH was evaluated in the murine model of vascular thrombosis. The SAK protein (1 mg/kg body mass) and SRH protein (1 mg/kg and 2 mg/kg) were administered intravenously to the different treatment groups. The results have shown a dose-dependent antithrombotic effect in carrageenan-induced mouse tail thrombosis. The thrombin time, activated partial thromboplastin time, and prothrombin time were significantly prolonged (p < 0.05) in the SRH-infused groups. Moreover, SRH inhibited platelet aggregation in a dose-dependent manner (p < 0.05), while the bleeding time was significantly (p < 0.05) prolonged. All of these results inferred that the osmotically produced multifunctional fusion protein SRH (SAK-RGD-Hirulog) is a promising thrombolytic agent, and one which sustained its multifunctionality in the animal models.

Topics: Animals; Antithrombins; Blood Coagulation; Carrageenan; Disease Models, Animal; Dose-Response Relationship, Drug; Escherichia coli; Hirudins; Male; Metalloendopeptidases; Mice; Mice, Inbred BALB C; Oligopeptides; Partial Thromboplastin Time; Peptide Fragments; Platelet Aggregation; Platelet Aggregation Inhibitors; Prothrombin Time; Rats; Rats, Sprague-Dawley; Recombinant Fusion Proteins; Recombinant Proteins; Sodium Chloride; Thrombin Time; Thrombosis; Time Factors

Glycoprotein IIb-IIIa (GPIIb-IIIa) antagonists have the capacity to destabilize coronary thrombi and restore vessel patency. Antagonist concentration and residence time, which can be increased by local intracoronary (LIC) administration, and thrombus age may be key factors that influence thrombus stability. Light transmission aggregometry was used to examine the effects of exposing human platelet aggregates to extremely high local levels of GPIIb-IIIa antagonists versus conventional therapeutic levels in vitro. Freshly-formed or aged platelet aggregates were subjected to GPIIb-IIIa antagonists (abciximab, eptifibatide) or direct thrombin inhibitor bivalirudin at concentrations simulating either conventional intravenous (IV) or LIC administration. The degree of antagonist-induced disaggregation was significantly higher using elevated (LIC) doses versus conventional (IV) doses (60.1 % vs. 7.4 % for abciximab, 41.6 % or 45.3 % vs. 17.6 % for eptifibatide, p < 0.01). Bivalirudin did not promote disaggregation. Microscopy confirmed noticeably smaller, more dispersed aggregates for antagonist LIC treatments. Dosing at LIC levels also induced more disaggregation than IV levels when aggregates were aged for 30 min prior to exposure. An in vitro perfusion model was used to simulate the fluid dynamics of IV or LIC administration of abciximab using a microporous local drug delivery balloon catheter such as the Atrium ClearWay™ RX. The perfusion model resulted in more rapid thrombus clearance with LIC dosing levels compared to IV. In summary, boosting the concentration of GPIIb-IIIa antagonists enhances dispersal of human platelet aggregates in vitro. These data provide a foundation for investigating increased local concentrations of GPIIb-IIIa antagonists in patients, as with LIC administration.

Topics: Abciximab; Antibodies, Monoclonal; Antithrombins; Coronary Vessels; Eptifibatide; Female; Hirudins; Humans; Immunoglobulin Fab Fragments; Male; Peptide Fragments; Peptides; Platelet Aggregation; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Thrombosis

Limited data are available regarding adverse bleeding events associated with antithrombotic agents incorrectly dosed based on renal function in patients receiving percutaneous coronary intervention (PCI).. To compare the incidence of bleeding during their hospital stay in patients with reduced renal function receiving incorrect doses of bivalirudin or eptifibatide to the incidence of correct doses, based on manufacturer recommendations; secondary objectives were to determine the incidence of correct dosing based on manufacturer recommendations and the incidence of TIMI (Thrombolysis in Myocardial Infarction) major bleeding.. A chart review over a 32-month period showed that patients with reduced renal function who received either eptifibatide or bivalirudin during PCI were evaluated for correct dosing based on manufacturer recommendations, bleeding incidence according to the TIMI criteria, and extent of bleeding according to the TIMI and GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) criteria.. One hundred ninety patients met inclusion criteria, 56 who received eptifibatide and 134 who received bivalirudin. Eptifibatide was dosed incorrectly in 64% of the patients. Patients receiving incorrectly dosed compared to correctly dosed eptifibatide experienced significantly more bleeding (64% vs 35%, respectively, p = 0.04), a greater extent of bleeding based on the TIMI and GUSTO criteria (p = 0.03 and p = 0.009, respectively), and had more TIMI major bleeding (19% vs 5%, respectively). Bivalirudin was dosed incorrectly in 28% of the patients. Patients receiving incorrectly dosed compared to correctly dosed bivalirudin experienced a significantly greater extent of bleeding based on the GUSTO criteria (p = 0.01). There was no significant difference between the incidence of bleeding (37% vs 21%, respectively; p = 0.06), extent of bleeding based on the TIMI criteria (p = 0.058), or incidence of TIMI major bleeding (5% vs 3%).. Patients receiving incorrectly dosed eptifibatide and bivalirudin are susceptible to adverse bleeding events. The occurrence of incorrect dosing offers an opportunity for pharmacist-driven institutional improvement.

Topics: Aged; Angioplasty, Balloon, Coronary; Antithrombins; Eptifibatide; Female; Glomerular Filtration Rate; Hemorrhage; Hirudins; Humans; Incidence; Male; Medical Records Systems, Computerized; Medication Errors; Middle Aged; Peptide Fragments; Peptides; Practice Guidelines as Topic; Recombinant Proteins; Renal Insufficiency; Thrombosis

Thrombin a key modulator of the complex process involved in coronary obstruction during acute ST-segment elevation myocardial is infarction. A correct and complete thrombin inhibition has to be achieved early in this setting and is complementary with fast and potent antiplatelet treatment. Bivalirudin, a direct thrombin inhibitor, has clearly shown to be an effective tool for acute coronary syndromes managed invasively, contemporarily causing fewer hemorragies. However, its efficacy has been questioned, mostly in cases of inadequate platelet inhibition and during primary PCI if compared with therapy with heparin and glycoprotein IIb/IIIa inhibitors due to an increase in acute stent thrombosis. Other modalities of infusion have been shown to improve the antithrombotic properties of bivalirudin, maintaining its safety profile. In this article, we discuss on the most recent studies on this drug in the catheterization laboratory during acute myocardial infarction.

Topics: Angioplasty, Balloon, Coronary; Antithrombins; Arrhythmias, Cardiac; Combined Modality Therapy; Hemorrhage; Hirudins; Humans; Infusions, Parenteral; Myocardial Infarction; Peptide Fragments; Platelet Aggregation Inhibitors; Postoperative Care; Recombinant Proteins; Risk; Thrombosis

Topics: Acute Coronary Syndrome; Age Factors; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Antithrombins; Feasibility Studies; Female; Hemorrhage; Hirudins; Humans; Male; Myocardial Infarction; Peptide Fragments; Prospective Studies; Radial Artery; Recombinant Proteins; Registries; Risk Assessment; Risk Factors; Thrombosis; Time Factors; Treatment Outcome

Anticoagulation therapy during percutaneous coronary intervention (PCI) has been the focus of numerous clinical trials. Low-anticoagulant doses have been successfully used in patients undergoing elective PCI, a situation with low-thrombogenic milieu.. The purpose of the study was to evaluate the safety and efficacy of shorter duration of treatment with bivalirudin in patients undergoing elective PCI and receiving optimal antiplatelet therapy.. We compared patients undergoing PCI who received aspirin and clopidogrel loading dose in addition to either conventional bivalirudin dosing (intravenous [IV] bolus of 0.75 + 1.75 mg/kg per h for the duration of PCI; n = 197) or a reduced bivalirudin dose (IV bolus of 0.75 mg/kg; n = 200).. Procedural success was obtained in 100% of cases. The primary end point (in-hospital death, acute myocardial infarction, or need for urgent target vessel revascularization) did not differ between both the groups (6 patients [3%] in the conventional dose group vs 5 patients [2.5%] in the reduced dose group). Major bleeding occurred in 1 patient in the conventional dose group (P = nonsignificant [NS]). Minor bleeding occurred in 4 patients (2%) in the conventional dose group vs 5 patients (2.5%) in the reduced dose group (P = NS) and was mainly due to bleeding at entry site.. In patients undergoing elective PCI, using bivalirudin as a bolus only dosing may be as effective and less costly when compared with bolus followed by an infusion for the duration of the intervention. A larger study is needed to confirm our findings.

Topics: Aged; Alabama; Antithrombins; Aspirin; Clopidogrel; Dose-Response Relationship, Drug; Elective Surgical Procedures; Female; Hemorrhage; Hirudins; Humans; Incidence; Infusions, Intravenous; Injections, Intravenous; Ischemia; Male; Middle Aged; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Recombinant Proteins; Retrospective Studies; Severity of Illness Index; Thrombosis; Ticlopidine

Data from randomized trials has demonstrated the superiority of bivalirudin to glycoprotein IIb/IIIa inhibitors plus heparin in patients undergoing primary percutaneous coronary intervention. Real-world performance of bivalirudin in primary percutaneous coronary intervention and the benefit of bivalirudin over heparin remain unknown in an era of routine dual antiplatelet therapy.. From July 2004 to December 2010, 2317 consecutive patients were indexed in the University of Ottawa Heart Institute ST-segment-elevation myocardial infarction registry. During this period 748 patients received bivalirudin, 699 patients received glycoprotein IIb/IIIa inhibitors, and 676 patients received unfractionated heparin alone. The primary outcome was the rate of noncoronary artery bypass graft related thrombolysis in myocardial infarction major bleeding. Bivalirudin significantly reduced the primary outcome compared with heparin plus glycoprotein IIb/IIIa inhibitors (2.7% versus 7.3%, adjusted OR 2.96, 95% CI: 1.61-5.45, P<0.001) and the composite end point of death, stroke, reinfarction and major bleed (OR 1.66, 95% CI: 1.12-2.45, P=0.01). Compared with heparin alone, a reduction in major bleeds (OR 1.21, 95% CI: 0.60-2.44, P=0.59) or the composite end point (1.05, 95% CI: 0.68-1.63, P=0.83) with bivalirudin could not be demonstrated. Notably, major bleeding was associated with a 5-fold increase in the risk of mortality both in-hospital (3.5% versus 20.6%) and out to 180 days (5.6% versus 25.8%).. Bivalirudin use compared with glycoprotein IIb/IIIa inhibitors plus heparin as an antithrombotic strategy in primary percutaneous coronary intervention results in less major bleeding in contemporary practice. A benefit of bivalirudin over heparin could not be established with this registry and requires additional investigations to either confirm or refute.

Topics: Aged; Anticoagulants; Antithrombins; Chi-Square Distribution; Drug Therapy, Combination; Female; Fibrinolytic Agents; Hemorrhage; Heparin; Hirudins; Hospital Mortality; Hospitals, University; Humans; Logistic Models; Male; Middle Aged; Myocardial Infarction; Odds Ratio; Ontario; Peptide Fragments; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Propensity Score; Recombinant Proteins; Recurrence; Registries; Risk Factors; Stroke; Thrombosis; Time Factors; Treatment Outcome

Thrombin-generation and activation of platelets during percutaneous coronary intervention (PCI) play a key role for early thrombotic events. Heparin and bivalirudin are approved anticoagulants for PCI. We examined the specific effects of these anticoagulants on platelet adhesion and aggregation under high shear conditions, and the presence of excess thrombin. To simulate in vivo conditions that may precipitate a bleeding/thrombotic event, we added thrombin in vitro to blood samples from 89 stable patients who had been randomly assigned to receive heparin or bivalirudin for elective PCI and examined thrombin-inducible platelet adhesion and aggregation under high shear conditions. Platelet adhesion increased by 10% of baseline with heparin, but decreased by 20% with bivalirudin (p=0.0047). Thrombin-inducible platelet adhesion and size of aggregates was equally inhibited by heparin and bivalirudin. Thus, under high shear conditions and excessive thrombin generation as they occur in atherosclerotic vascular compartments and acute vascular syndromes, heparin and bivalirudin inhibit thrombin-induced platelet adhesion and aggregation to a similar extent, while they have opposite effects on platelet adhesion in the absence of thrombin.

Topics: Aged; Angioplasty, Balloon, Coronary; Anticoagulants; Female; Hemorrhage; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Platelet Adhesiveness; Platelet Aggregation; Recombinant Proteins; Shear Strength; Thrombin; Thrombosis

Thrombin inhibition is an important objective in the prevention and treatment of thrombosis. A new molecule, dabigatran etexilate or Pradaxa(®), has been recently licensed for thromboprophylaxis in major orthopedic surgery in several countries but not in the USA. In contrast, the FDA has approved it for prevention in patients with non-valvular atrial fibrillation. This new orally active anticoagulant is being developed for the treatment of venous thromboembolism and acute coronary syndromes in patients with non-valvular atrial fibrillation. Dabigatran is a reversible inhibitor of free thrombin and clot-bound thrombin. An oral thrombin inhibitor melagatran is no longer available due to hepatic toxicity. Several other thrombin inhibitors are used via parenteral administration: lepirudine and desirudine, bivalirudine and argatroban. They are mostly given to patients with heparin-induced thrombocytopenia (HIT). Bivalirudine is used for acute coronary syndrome in patients undergoing percutaneous interventions. The main pharmacologic characteristics of thrombin inhibitor agents are presented focusing on dabigatran etexilate and including the main results of clinical trials.

Topics: Anticoagulants; Antithrombins; Benzimidazoles; Contraindications; Dabigatran; Drug Interactions; Heparin; Hirudin Therapy; Hirudins; Humans; Orthopedic Procedures; Peptide Fragments; Postoperative Complications; Pyridines; Recombinant Proteins; Thrombocytopenia; Thrombosis; Venous Thrombosis

Although clopidogrel pretreatment benefits patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndromes, these benefits are less well established among patients undergoing elective PCI--in particular, when they are treated with the direct thrombin inhibitor, bivalirudin. We used data from the multicenter Evaluation of Drug Eluting stents and ischemic Events registry to assess the association between clopidogrel pretreatment and PCI-related complications among patients undergoing elective PCI with bivalirudin as the antithrombotic regimen. The primary end point was the composite of in-hospital death or myocardial infarction. From January 2005 and December 2007, 4,681 patients underwent elective PCI at 55 United States centers, and 1,913 (41%) received bivalirudin as the planned anticoagulant. Clopidogrel pretreatment was used in 923 patients (48%). The incidence of in-hospital death or myocardial infarction was similar among patients who did and did not receive clopidogrel pretreatment (5.5% vs 5.8%, p = 0.83). This result was unchanged in propensity-adjusted analyses (adjusted odds ratio for pretreatment 0.91, 95% confidence interval 0.60 to 1.39, p = 0.66). Also, no differences were seen in the in-hospital bleeding events (1.0% vs 1.0%, p = 0.94) or 1-year ischemic complications between the 2 treatment groups (7.5% vs 8.3%, p = 0.26). In conclusion, among unselected patients undergoing elective PCI with bivalirudin as the planned anticoagulant, clopidogrel pretreatment was common but was not associated with a reduced risk of ischemic complications.

Topics: Acute Coronary Syndrome; Aged; Angioplasty, Balloon, Coronary; Antithrombins; Clopidogrel; Female; Hemorrhage; Hirudins; Humans; Male; Middle Aged; Myocardial Infarction; Peptide Fragments; Platelet Aggregation Inhibitors; Premedication; Recombinant Proteins; Thrombosis; Ticlopidine

Topics: Angioplasty, Balloon, Coronary; Cardiovascular Agents; Drug-Eluting Stents; Fibrinolytic Agents; Hirudins; Humans; Myocardial Infarction; Paclitaxel; Peptide Fragments; Prosthesis Design; Randomized Controlled Trials as Topic; Recombinant Proteins; Thrombosis; Time Factors; Treatment Outcome

Topics: Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Cohort Studies; Drug Therapy, Combination; Female; Hemorrhage; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Piperazines; Prasugrel Hydrochloride; Recombinant Proteins; Stents; Thiophenes; Thrombosis; Time Factors

Successful management of acute cardiac tamponade secondary to coronary artery perforation during percutaneous coronary intervention (PCI) includes sealing off the site of perforation and pericardiocentesis. We report two cases of acute cardiac tamponade during PCI associated with the administration of bivalirudin, in which attempts at percutaneous pericardiocentesis failed, due to the present of thrombus, rather blood, in the pericardium.

Topics: Acute Disease; Aged, 80 and over; Angioplasty, Balloon, Coronary; Anticoagulants; Cardiac Tamponade; Coronary Artery Disease; Coronary Vessels; Female; Heart Injuries; Hemostatic Techniques; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Pericardiectomy; Pericardiocentesis; Recombinant Proteins; Stents; Sternotomy; Thrombosis; Treatment Failure; Ultrasonography; Wounds, Penetrating

Arterial puncture closure devices have improved time to hemostasis and ambulation after percutaneous coronary intervention (PCI) relative to traditional manual compression, though complication rates for both methods leave room for improvement. In a pilot registry, the authors evaluated a topical hemostatic dressing containing poly-N-acetyl glucosamine (p-GlcNAc) post PCI in fully anticoagulated patients.. In 100 patients undergoing PCI via the common femoral artery in the short-stay unit, the p-GlcNAc hemostatic dressing was applied with 15 minutes of manual compression at arterial access sites after arterial sheath removal. Procedural antiplatelet and anticoagulation therapies were aspirin, clopidogrel and bivalirudin. Patients were observed during 2 hours of bed rest and attempted to ambulate 2 hours post hemostasis. Effectiveness was assessed based on times to hemostasis and ambulation. Data were stratified by time elapsed since bivalirudin bolus or discontinuation of infusion (30 minutes, > 30-60 minutes, > 60 minutes). Mean time to hemostasis was 15.5 minutes. Mean time from hemostasis to ambulation was 2.08 hours; 87% of patients ambulated at 2 hours. Sheaths were removed at a mean 40.38 minutes after discontinuing bivalirudin. Anticoagulation status (as assessed by time since discontinuation of bivalirudin) did not influence time to hemostasis or ambulation. There was a single major complication (pseudoaneurysm), two minor rebleeds requiring additional manual compression, and 1 hematoma > 5 cm.. This p-GlcNAc topical hemostatic dressing safely achieved hemostasis at arterial access sites and early ambulation, even with nearly immediate sheath removal after PCI with systemic anticoagulation using bivalirudin.

Topics: Acetylglucosamine; Administration, Topical; Aged; Angioplasty, Balloon, Coronary; Anticoagulants; Biological Dressings; Female; Femoral Artery; Hemostasis; Hemostatics; Hirudins; Humans; Male; Peptide Fragments; Pilot Projects; Recombinant Proteins; Regional Blood Flow; Retrospective Studies; Thrombosis; Time Factors; Walking

The present study aimed to assess whether the fibrin network structure is modified by the direct thrombin-inhibitors lepirudin, argatroban or bivalirudin and by the indirect Xa-inhibitor danaparoid. Using an in vitro assay that imitates the physiological process of coagulation from thrombin generation to fibrin formation, we examined a normal plasma pool spiked with one of the inhibitors. At concentrations considered to be the plasma levels observed during therapy, almost no influence was detected for lepirudin despite clear-cut effects on "clotting time". However, argatroban, bivalirudin and danaparoid increased the fibrin gel permeability (Ks) to a similar extent. At concentrations higher than the "therapeutic" levels, the dose-response curve in the Ks assay became very steep for lepirudin while those were shallow for the others. In parallel with the drug-induced increases of Ks, larger network pores in 3D-microscopic images and significant shortenings in "clot lysis time" induced by addition of rtPA were observed. Recombinant factor VIII (rFVIII) added to danaparoid-treated samples profoundly counteracted the increase of Ks but had only a slight or no effect on the other drugs. Thus, in vitro, argatroban, bivalirudin and danaparoid have comparable anticoagulating effects, rendering the fibrin network more permeable and less resistant to fibrinolysis. For lepirudin, the steep dose-response curve supports previous clinical findings, i.e. this thrombin inhibitor has a narrow therapeutic window. Furthermore, our data suggest that the haemostatic agent, rFVIII, might be effective in treatment of bleeding complications induced by danaparoid.

Topics: Antithrombins; Arginine; Chondroitin Sulfates; Chromatography, Gel; Dermatan Sulfate; Factor VIII; Factor Xa Inhibitors; Fibrin; Fibrinolysis; Heparinoids; Heparitin Sulfate; Hirudins; Humans; In Vitro Techniques; Microscopy, Confocal; Peptide Fragments; Pipecolic Acids; Plasma; Porosity; Protein Multimerization; Recombinant Proteins; Sulfonamides; Thrombosis; Tissue Plasminogen Activator

Anticoagulant therapy is a major component in the management of acute coronary syndromes (ACS). Four anticoagulant agents are currently commercially available for ACS, namely unfractionated heparin (UFH), enoxaparin, bivalirudin and fondaparinux. We describe the advantages of fondaparinux and the reasons that have hampered its uptake into routine management of ACS. Fondaparinux was shown to be efficacious in the prevention of deep vein thrombosis vs low-molecular-weight heparins, while in the setting of venous thrombo-embolic disease, it was shown to be noninferior to enoxaparin and UFH. Two pivotal studies have demonstrated the efficacy of fondaparinux as an anticoagulant in the setting of ACS, namely OASIS-5 in non-ST elevation ACS, and OASIS-6 in ST elevation myocardial infarction (MI). In OASIS-5, fondaparinux was shown to be noninferior to enoxaparin in terms of death, MI or refractory ischemia at 9 days. Furthermore, a 50% reduction in bleeding complications was obtained with fondaparinux vs enoxaparin, leading to a risk reduction for death. In OASIS-6, fondaparinux was shown to be superior to the comparator (UFH or placebo). European and North American guidelines give fondaparinux a Grade 1A and 1B recommendation respectively, but uptake of fondaparinux in routine practice has been slow. We explore reasons for this, such as prevailing doubts about the efficacy of fondaparinux in the setting of angioplasty, the problem of catheter thrombosis, and the lack of antidote in case of bleeding complications. With the exception of primary angioplasty, fondaparinux is as effective as enoxaparin or UFH, but is also associated with a considerable reduction in bleeding complications, and thus, an undeniable net clinical benefit.

Topics: Acute Coronary Syndrome; Anticoagulants; Catheterization; Enoxaparin; Fondaparinux; Hirudins; Humans; Peptide Fragments; Polysaccharides; Recombinant Proteins; Thrombosis

The association between obesity and bleeding after percutaneous coronary intervention (PCI) is not well defined. We investigated the impact of body mass index (BMI) on PCI-related bleeding, and whether bivalirudin, compared to heparin, used as PCI anticoagulant modifies this relationship.. From 2000 to 2009, 16,783 patients who underwent PCI were grouped according to 6 BMI groups: underweight (<18.5 kg/m(2)), "normal" weight (18.5-24.9 kg/m(2)), overweight (25-29.9 kg/m(2)), class I (30-34.9 kg/m(2)), class II (35-39.9 kg/m(2)), and class III obesity (> or =40 kg/m(2)). Bivalirudin was used in 11,433 patients and heparin in 5,350. In-hospital major bleeding (hematocrit drop > or =15% or gastrointestinal bleeding) and need for transfusion rates were collected.. The incidence of major bleeding varied significantly throughout the BMI spectrum (5.6% vs 2.5% vs 1.9% vs 1.6% vs 2.1% vs 1.9%, respectively, from underweight to class III obese patients, P < .001). The incidence of transfusion across BMI followed the same reverse J-shape curve (10.9% vs 6.6% vs 3.6% vs 3.4% vs 3.8% vs 5.6%, P < .001). After adjustment for potential confounding factors, underweight patients had neither an increased risk for major bleeding nor an increased risk for transfusion compared with "normal" weight patients. Class I obese patients had a lower risk of major bleeding (odds ratio [OR] 0.68 [95% CI 0.48-0.97]). Overweight, class I, and II obese patients had a lower risk of transfusion (respectively, OR 0.68 [0.55-0.84], 0.68 [0.53-0.87], and 0.66 [0.48-0.92]). The highest BMI patients had neither an increased risk for major bleeding (class II and III obesity) nor an increased risk for transfusion (class III obesity). The same reverse J-shaped relationship to BMI seen in the overall population for the raw incidence of major bleeding was found when the population was divided according to type of anticoagulant used as follows: bivalirudin or heparin. Likewise, the "need for transfusion" relationship to BMI is not altered by bivalirudin use.. The better outcome for bleeding seen in patients in the middle of the BMI spectrum suggests the existence of a "bleeding obesity paradox," which persists after adjustment by confounding factors and exists irrespective of the anticoagulant used.

Topics: Aged; Angioplasty, Balloon, Coronary; Anticoagulants; Antithrombins; Body Mass Index; Coronary Disease; Female; Follow-Up Studies; Hirudins; Humans; Incidence; Male; Middle Aged; Obesity; Odds Ratio; Peptide Fragments; Postoperative Hemorrhage; Prognosis; Recombinant Proteins; Retrospective Studies; Risk Factors; Thrombosis

The aim of this study was to examine the use of and outcomes associated with antithrombotic strategies in patients with non-ST-segment elevation myocardial infarction (NSTEMI) who undergo percutaneous coronary intervention (PCI).. A variety of antithrombotic strategies have been tested in clinical trials for NSTEMI patients treated with PCI.. Antithrombotic strategies for NSTEMI patients undergoing PCI at 217 ACTION (Acute Coronary Treatment and Intervention Outcomes Network) hospitals from January 1, 2007, to December 31, 2007, (n = 11,085) were classified into commonly observed antithrombotic groups: heparin alone (Hep alone; low-molecular-weight heparin or unfractionated heparin), bivalirudin alone (Bival alone), heparin with glycoprotein IIb/IIIa inhibitors (Hep/GPI), and bivalirudin with GPI (Bival/GPI). Baseline characteristics are shown across treatment groups. In addition, unadjusted and adjusted rates of in-hospital major bleeding and death are shown.. The standard strategy used was Hep/GPI (64%), followed by Hep or Bival alone (28%), and Bival/GPI (8%). Patients who received Hep or Bival alone were older with more comorbidities, higher baseline bleeding and mortality risk, and lower peak troponin. Compared with patients who received Hep/GPI , those who received Hep alone and Bival alone had lower rates of major bleeding (adjusted odds ratio [OR]: 0.52; 95% confidence interval [CI]: 0.42 to 0.65; adjusted OR: 0.48; 95% CI: 0.39 to 0.60; respectively), yet only patients who received Bival alone had lower mortality (adjusted OR: 0.39; 95% CI: 0.21 to 0.71).. NSTEMI patients undergoing PCI are more likely to receive Bival or Hep alone when at higher baseline bleeding risk than when at lower baseline bleeding risk. Despite higher baseline risk, those receiving Bival or Hep alone had less bleeding.

Topics: Aged; Angioplasty, Balloon, Coronary; Chi-Square Distribution; Drug Therapy, Combination; Female; Fibrinolytic Agents; Hemorrhage; Heparin; Hirudins; Hospital Mortality; Humans; Logistic Models; Male; Middle Aged; Myocardial Infarction; Odds Ratio; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Registries; Risk Assessment; Risk Factors; Thrombosis; Time Factors; Treatment Outcome; United States

Topics: Angioplasty, Balloon, Coronary; Drug Therapy, Combination; Fibrinolytic Agents; Hemorrhage; Heparin; Hirudins; Hospital Mortality; Humans; Myocardial Infarction; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Risk Assessment; Risk Factors; Thrombosis; Time Factors; Treatment Outcome

Direct thrombin inhibitors are heparin alternatives for anticoagulation during cardiopulmonary bypass in patients with heparin-induced thrombocytopenia. We report a case of a large thrombus forming in the venous reservoir while using bivalirudin. We suggest that blood stasis associated with the full venous reservoir maintained in this case led to formation of a large thrombus at the top of the venous canister. Furthermore, activated clotting times may not accurately reflect the magnitude of anticoagulation when using direct thrombin inhibitors.

Topics: Anticoagulants; Antithrombins; Cardiomyopathy, Dilated; Fibrinolysis; Heart Transplantation; Heparin; Hirudins; Humans; Intra-Aortic Balloon Pumping; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Thrombocytopenia; Thrombosis; Treatment Failure; Whole Blood Coagulation Time

Prevention of valve thrombosis in patients after prosthetic mechanical heart valve replacement and heparin-induced thrombocytopenia (HIT) is still an open issue. The aim of the present in-vitro study was to investigate the efficacy of argatroban and bivalirudin in comparison to unfractionated heparin (UFH) in preventing thrombus formation on mechanical heart valves. Blood (230 ml) from healthy young male volunteers was anticoagulated either by UFH, argatroban bolus, argatroban bolus plus continuous infusion, bivalirudin bolus, or bivalirudin bolus plus continuous infusion. Valve prostheses were placed in a newly developed in-vitro thrombosis tester and exposed to the anticoagulated blood samples. To quantify the thrombi, electron microscopy was performed, and each valve was weighed before and after the experiment. Mean thrombus weight in group 1 (UFH) was 117 + 93 mg, in group 2 (argatroban bolus) 722 + 428 mg, in group 3 (bivalirudin bolus) 758 + 323 mg, in group 4 (argatroban bolus plus continuous infusion) 162 + 98 mg, and in group 5 (bivalirudin bolus plus continuous infusion) 166 + 141 mg (p-value <0.001). Electron microscopy showed increased rates of thrombus formation in groups 2 and 3. Argatroban and bivalirudin were as effective as UFH in preventing thrombus formation on valve prostheses in our in-vitro investigation when they were administered continuously. We hypothesise that continuous infusion of argatroban or bivalirudin are optimal treatment options for patients with HIT after mechanical heart valve replacement for adapting oral to parenteral anticoagulation or vice versa.

Topics: Anticoagulants; Arginine; Diagnostic Techniques, Cardiovascular; Drug Therapy, Combination; Feasibility Studies; Heart Diseases; Heart-Assist Devices; Heparin; Hirudins; Humans; In Vitro Techniques; Infusion Pumps; Male; Peptide Fragments; Pipecolic Acids; Recombinant Proteins; Sulfonamides; Thrombin; Thrombocytopenia; Thrombosis

Topics: Abciximab; Angioplasty, Balloon, Coronary; Antibodies, Monoclonal; Drug Therapy, Combination; Embolism; Eptifibatide; Hemorrhage; Hirudins; Humans; Immunoglobulin Fab Fragments; Peptide Fragments; Peptides; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Thrombosis; Treatment Outcome

This study sought to evaluate the frequency and efficacy of combination of bivalirudin and provisional glycoprotein (GP) IIb/IIIa blockade compared with bivalirudin monotherapy in current clinical practice of percutaneous coronary intervention (PCI) with drug-eluting stents (DES).. Previous randomized trials have demonstrated that a strategy of bivalirudin with provisional (bailout) GP IIb/IIIa inhibition was non-inferior to unfractionated heparin (UFH) plus planned GP IIb/IIIa blockade for the prevention of acute and long-term adverse clinical events. However, the frequency and efficacy of provisional GP IIb/IIIa inhibition in addition to the full-dose bivalirudin in current practice is not well established.. Using the 2004/2005 Cornell Angioplasty Registry, we studied 1,340 consecutive patients undergoing urgent or elective PCI with periprocedural use of bivalirudin. We excluded patients presenting with an acute ST-elevation myocardial infarction (MI) within < or = 24 hours, hemodynamic instability/shock, thrombolytic therapy within < or = 7 days, or renal insufficiency. Mean clinical follow up was 24.2 +/- 7.7 months.. Of the study cohort, 1,184 patients (88.4%) received bivalirudin alone and 156 (11.6%) received bivalirudin plus bailout GP IIb/IIIa blockade. DES were used in 86% of PCIs. The incidence of in-hospital mortality (0% vs. 0.3% p = 1.000), MI (7.1% vs. 6.6%; p = 0.864), and the combined endpoint of death, stroke, emergent coronary artery bypass graft surgery (CABG)/PCI, or MI (7.1% vs. 6.9%; p = 0.868) were similar in the bivalirudin-plus-bailout GP IIb/IIIa inhibitor versus the bivalirudin-alone arm. There was a higher incidence of bleeding complications (16.0% vs. 9.6%; p = 0.018) in the bivalirudin-plus-bailout GP IIb/IIIa versus the bivalirudin-alone group. At follow up, there were 4 (2.6%) deaths in the bivalirudin-plus-GP IIb/IIIa inhibitor group versus 83 (7.0%) deaths in the bivalirudin-alone arm (HR 0.36, 95% confidence interval [CI] 0.13-0.98; p = 0.044). After multivariate Cox regression analysis, bailout GP IIb/IIIa use in addition to bivalirudin was associated with similar long-term survival when compared to bivalirudin monotherapy (HR 0.41, 95% CI 0.15-1.12; p = 0.081).. Provisional GP IIb/IIIa use in bivalirudin-treated patients is higher in contemporary non-emergent PCI practice than that seen in randomized trials and is associated with similar in-hospital ischemic events, but more frequent bleeding events. These data suggest that a strategy of bivalirudin monotherapy is preferable in order to reduce bleeding complications, and GP IIb/IIIa blockade should be reserved for patients with periprocedural complications in bivalirudin-treated patients undergoing PCI.

Topics: Abciximab; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Antibodies, Monoclonal; Anticoagulants; Aspirin; Clopidogrel; Drug Therapy, Combination; Embolism; Eptifibatide; Female; Follow-Up Studies; Hirudins; Humans; Immunoglobulin Fab Fragments; Male; Middle Aged; Peptide Fragments; Peptides; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Registries; Regression Analysis; Retrospective Studies; Thrombosis; Ticlopidine; Treatment Outcome

Topics: Acute Coronary Syndrome; Angioplasty, Balloon, Coronary; Anticoagulants; Hemorrhage; Heparin; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Practice Guidelines as Topic; Recombinant Proteins; Stents; Thrombosis

The aim of this study was to determine the efficacy and safety of bivalirudin versus low-dose unfractionated heparin (UFH) in percutaneous peripheral intervention (PPI).. Anticoagulation strategies used in PPI are based primarily on studies of percutaneous coronary intervention where higher doses of heparin are used usually in combination with a glycoprotein IIb/IIIa inhibitor. There are no studies comparing bivalirudin alone versus low-dose heparin in PPI.. Consecutive patients who underwent PPI at our institution were treated with either bivalirudin or low-dose UFH. Patients were assessed prospectively during index hospital stay for procedural success and bleeding complications. Of 236 patients, 111 were dosed with UFH at 50 U/kg (goal activated clotting time of 180 to 240 s), and 125 were dosed with bivalirudin at 0.75-mg/kg/h bolus followed by a 1.75-mg/kg infusion. Procedural success was defined as <20% post-procedure residual stenosis with no flow-limiting dissections or intravascular thrombus formation and major bleeding as intracranial or retroperitoneal hemorrhage or a fall in hemoglobin >or=5 g/dl. Anticoagulation cost analysis was conducted.. Procedural success and major bleeding rates were similar with bivalirudin versus heparin (98% vs. 99% and 2.4% vs. 0.9%, respectively). There were no differences in minor bleeding, time to ambulation, and length of hospital stay. The hospital cost for bivalirudin was $547 and <$1.22 for heparin (10,000 U). Two activated clotting time levels cost $4.00.. Low-dose UFH is as effective and safe as bivalirudin when used as an anticoagulation strategy in patients undergoing PPI, and low-dose UFH is less costly than bivalirudin. Larger randomized studies are required to further evaluate these findings.

Topics: Aged; Aged, 80 and over; Angioplasty; Anticoagulants; Cost-Benefit Analysis; Drug Costs; Female; Hemorrhage; Heparin; Hirudins; Hospital Costs; Humans; Length of Stay; Male; Middle Aged; Peptide Fragments; Peripheral Vascular Diseases; Prospective Studies; Recombinant Proteins; Stents; Thrombosis; Time Factors; Treatment Outcome; Walking

Topics: Aged; Anticoagulants; Blindness, Cortical; Brain Infarction; Heparin; Hirudins; Humans; Male; Mesenteric Arteries; Occipital Lobe; Peptide Fragments; Recombinant Proteins; Thrombocytopenia; Thrombosis; Tomography, X-Ray Computed; Treatment Outcome

Type II heparin-induced thrombocytopenia (HIT) is an immune-mediated syndrome that may arise in a time-dependent manner following heparin therapy, placing patients at significant risk for thromboembolic events. Therapy includes anticoagulation with a direct thrombin inhibitor and avoidance of heparin. We report a patient with Budd-Chiari syndrome and a history of heparin-induced thrombocytopenia who presented for orthotopic liver transplant and required postoperative anticoagulation with bivalirudin. During the post-transplant graft function improvement, we observed a significant dose-effect alteration manifested by an increased bivalirudin dose requirement as factor V activity increased. This observation is an important consideration in the attempt to maintain an optimal balance between effective anticoagulation and a reduced risk of postoperative bleeding.

Topics: Adult; Anticoagulants; Blood Coagulation; Budd-Chiari Syndrome; Dose-Response Relationship, Drug; Factor V; Heparin; Hirudins; Humans; Liver; Liver Transplantation; Male; Partial Thromboplastin Time; Peptide Fragments; Recombinant Proteins; Thrombocytopenia; Thrombosis

Thromboembolism in children is typically treated with unfractionated heparin (UH) or low molecular weight heparin (LMWH). Both rely on antithrombin (AT) for their action. In addition, heparin-induced thrombocytopenia (HIT) is a potentially serious complication of heparin use in children. Bivalirudin or other direct thrombin inhibitors may be a useful alternative to heparins in treating thrombosis in children.. We report a retrospective review to assess the efficacy and safety of bivalirudin in pediatric patients with thrombosis.. Sixteen children received bivalirudin for thrombosis or prevention of thrombosis at the Children's Hospital of Illinois from January 2005 to January 2007. Patients received a bolus dose of 0.25 mg/kg followed by a continuous infusion (0.16 +/- 0.07 mg kg(-1) hr(-1)) titrated to 1.5-2.5 times the baseline activated partial thromboplastin time (aPTT). Positive correlation between the bivalirudin average infusion rate and aPTT was observed in twelve patients. Ultrasonographic evidence of thrombus regression was noted at 72 hr in 10 of 10 patients. One patient experienced hematuria after catheterization of the urethra.. Bivalirudin was effective and well-tolerated in these patients. Further studies should be conducted to better define safety and efficacy of bivalirudin in pediatric patients.

Topics: Adolescent; Anticoagulants; Antithrombins; Child; Child, Preschool; Female; Heparin; Hirudins; Humans; Infant; Infant, Newborn; Male; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Thrombocytopenia; Thrombosis; Treatment Outcome

The current standard of care for anti-thrombotic therapy with primary PCI for acute ST elevation myocardial infarction (STEMI) is aspirin, clopidogrel, unfractionated heparin and platelet glycoprotein IIb/IIIa inhibitors. However, heparin and glycoprotein IIb/IIIa inhibitors are associated with a high incidence of bleeding, and many of the trials documenting benefit with this therapy were performed before the widespread use of stents and clopidogrel. Bivalirudin is a direct thrombin inhibitor which has been found to have similar efficacy with less bleeding compared with heparin plus glycoprotein IIb/IIIa inhibitors when used with elective PCI and with PCI for unstable angina and non-ST elevation myocardial infarction. The HORIZONS trial evaluated bivalirudin compared with unfractionated heparin and IIb/IIIa inhibitors in patients with STEMI treated with primary PCI and found similar MACE (major adverse cardiac events) with less bleeding and a lower incidence of net adverse clinical events (MACE or major bleeding) at 30 days. Mortality at 30 days was also significantly less with bivalirudin. These results make a strong case for the use of bivalirudin with primary PCI in the great majority of patients with STEMI, with the possible exception of patients with cardiogenic shock or stent thrombosis, and patients with a large thrombus burden or no re-flow following PCI. In the latter case, platelet glycoprotein IIb/IIIa inhibitors would be used as a bail-out strategy.

Topics: Angioplasty, Balloon, Coronary; Anticoagulants; Aspirin; Cardiovascular Diseases; Clopidogrel; Fibrinolytic Agents; Hemorrhage; Heparin; Hirudins; Humans; Myocardial Infarction; Patient Selection; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Practice Guidelines as Topic; Randomized Controlled Trials as Topic; Recombinant Proteins; Research Design; Stents; Thrombin; Thrombosis; Ticlopidine; Treatment Outcome

Topics: Angioplasty, Balloon, Coronary; Anticoagulants; Antithrombins; Combined Modality Therapy; Heparin; Hirudins; Humans; Myocardial Infarction; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Recurrence; Research Design; Stents; Thrombosis

To compare clinical outcomes and glycoprotein IIb-IIIa inhibitor use in patients undergoing percutaneous coronary intervention (PCI) who received bivalirudin or unfractionated heparin (UFH) in a real-world setting.. Retrospective cohort analysis.. University-affiliated medical center.. One thousand seventy-five adult patients who underwent PCI and received either bivalirudin (539 patients) or UFH (536 patients) from April 1, 2003-April 1, 2004.. Patient data on demographics, comorbidities, laboratory values, and reports of radiologic examinations, cardiac catheterizations, and discharge summaries were obtained. Outcomes evaluated included rates of in-hospital mortality, myocardial infarction, revascularization, and length of stay (LOS), as well as Randomized Evaluation of PCI Linking Angiomax to Reduced Clinical Events (REPLACE-2) and Thrombosis in Myocardial Infarction (TIMI) bleeding categorization. Bivalirudin use was associated with a significant reduction in TIMI major (5.0% vs 9.7%, p=0.003), REPLACE-2 major (5.4% vs 12.9%, p<0.001), and TIMI minor (1.7% vs 6%, p<0.001) bleeding complications compared with UFH use. Significantly fewer patients in the bivalirudin group received glycoprotein IIb-IIIa inhibitors (27.3% vs 62.7%, p<0.001). Patients receiving bivalirudin had significantly fewer myocardial infarctions after catheterization (10.7% [40/375] vs 18.0% [51/284], p=0.007). No differences were noted in mortality and revascularization rates between groups. A shortened LOS was observed in the bivalirudin group.. This real-world analysis that included high-risk patients provides further evidence that bivalirudin is an attractive alternative to UFH because of a decrease in bleeding events without compromising efficacy.

Topics: Aged; Angioplasty, Balloon, Coronary; Anticoagulants; Cohort Studies; Female; Hemorrhage; Heparin; Hirudins; Hospitals, University; Humans; Length of Stay; Logistic Models; Male; Middle Aged; Multivariate Analysis; Myocardial Infarction; Myocardial Revascularization; Peptide Fragments; Platelet Aggregation Inhibitors; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Retrospective Studies; Risk Factors; Thrombosis; Treatment Outcome

Thrombin is the most potent agonist of platelets and plays a critical role in the development of arterial thrombosis. Human platelets express dual thrombin receptors, protease-activated receptor (PAR) 1 and PAR4; however, there are no therapeutic strategies that effectively target both receptors.. Platelet aggregation studies demonstrated that PAR4 activity is markedly enhanced by thrombin-PAR1 interactions. A combination of bivalirudin (hirulog) plus a novel PAR4 pepducin antagonist, P4pal-i1, effectively inhibited aggregation of human platelets to even high concentrations of thrombin and prevented occlusion of carotid arteries in guinea pigs. Likewise, combined inhibition of PAR1 and PAR4 with small-molecule antagonists and pepducins was effective against carotid artery occlusion. Coimmunoprecipitation and fluorescence resonance energy transfer studies revealed that PAR1 and PAR4 associate as a heterodimeric complex in human platelets and fibroblasts. PAR1-PAR4 cofactoring was shown by acceleration of thrombin cleavage and signaling of PAR4 on coexpression with PAR1.. We show that PAR1 and PAR4 form a stable heterodimer that enables thrombin to act as a bivalent functional agonist. These studies suggest that targeting the PAR1-PAR4 complex may present a novel therapeutic opportunity to prevent arterial thrombosis.

Topics: Animals; Blood Platelets; Cell Line; Chemotaxis; Dimerization; Disease Models, Animal; Drug Therapy, Combination; Guinea Pigs; Hirudins; Humans; Peptide Fragments; Platelet Aggregation; Protein Binding; Receptor, PAR-1; Receptors, Thrombin; Recombinant Proteins; Thrombin; Thrombosis; Transfection

Giant-cell myocarditis (GCM) is a rare, idiopathic disorder of young adults with high rates of morbidity and mortality. We describe a unique case of giant cell myocarditis associated with heparin-induced thrombocytopenia and thrombosis syndrome (HITTS). Our patient responded to therapy with bivalirudin, but later succumbed to complications from multiorgan failure. To our knowledge, this is the first reported case of GCM associated with HITTS, which was treated with bivalirudin (Angiomax; The Medicines Company; Parsippany, NJ).

Topics: Adult; Anticoagulants; Fatal Outcome; Giant Cells; Heparin; Hirudins; Humans; Male; Multiple Organ Failure; Myocarditis; Necrosis; Peptide Fragments; Recombinant Proteins; Thrombocytopenia; Thrombosis

Bivalirudin, a direct thrombin inhibitor, has recently emerged as a promising option for anti-coagulation during cardiopulmonary bypass in patients who cannot receive heparin. There is limited experience with the use of bivalirudin in children. We present the case of a child with heparin-induced thrombocytopenia with thrombosis (HIT Type II) who underwent successful orthotopic cardiac transplantation using bivalirudin as the primary anti-coagulant for cardiopulmonary bypass.

Topics: Anticoagulants; Cardiopulmonary Bypass; Child, Preschool; Dose-Response Relationship, Drug; Female; Heart Transplantation; Heparin; Hirudins; Humans; Peptide Fragments; Postoperative Complications; Recombinant Proteins; Thrombin; Thrombocytopenia; Thrombosis

Bivalirudin is shown to be a competent substitute for heparin in percutaneous coronary intervention (PCI). The safety and efficacy of bivalirudin in patients undergoing PCI and vascular brachytherapy (VBT) are not known. This study aimed to assess the safety and efficacy of bivalirudin as a single antithrombotic agent in patients undergoing PCI and VBT.. A total of 152 patients enrolled in the Brachytherapy and Bivalirudin Evaluation Study underwent PCI and VBT with either gamma (n = 8) or beta radiation (n = 144). The main outcome measures were in-hospital events and 30-day clinical outcomes. All patients were treated with bivalirudin (0.75 mg/kg bolus and 1.75 mg/kg per hour infusion for beta radiation, 1 mg/kg bolus and 2.5 mg/kg per hour infusion for gamma radiation) as a single antithrombotic agent during the entire procedure.. Baseline clinical and angiographic characteristics were similar between the 2 groups. More than 90% of the patients received beta radiation. In-hospital events showed a higher prevalence of acute procedural intracoronary thrombosis in patients treated with gamma- vs beta radiation (25% vs. 0.7%, P < .001). Thirty-day outcomes including death, Q-wave, and non-Q-wave myocardial infarctions, subacute stent thromboses, and repeat revascularizations were similar in both groups.. Bivalirudin, as a single antithrombotic agent during PCI and VBT with beta emitters, may be used safely, but its use in the setting of PCI and gamma radiation may not be acceptable due to an increased incidence of acute procedural intracoronary thrombosis.

Topics: Angioplasty, Balloon, Coronary; Anticoagulants; Brachytherapy; Coronary Stenosis; Female; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Thrombosis

Unfractionated heparin (UFH) does not effectively inhibit clot-bound thrombin and increases platelet reactivity, expression of P-selectin and inflammatory responses. These negative effects of UFH cannot be entirely overcome by the addition of a glycoprotein antagonist and may help explain the REPLACE-2 results.

Topics: Antithrombins; Blood Platelets; Clinical Trials as Topic; Hirudins; Humans; Inflammation; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Recombinant Proteins; Thrombin; Thrombosis

Subacute thrombosis is an infrequent but potentially life-threatening complication of percutaneous coronary intervention (PCI) that has received much attention in association with drug-eluting stent (DES) deployment. We performed a retrospective case record review of 186 patients receiving PCI with DES placement at our facility. Patients received either bivalirudin (n=115) or heparin (n=71) as the foundation anticoagulant, with additional antiplatelet therapy as warranted. Two subacute thrombosis complications occurred and are described in detail. There were no deaths, major bleeding episodes or other significant complications. We report our findings and conclude that the addition of a glycoprotein IIb/IIIa inhibitor does not eliminate the risk of subacute thrombosis and that bivalirudin appears to provide effective anticoagulation for patients undergoing PCI with placement of a DES.

Topics: Adult; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Anticoagulants; Blood Vessel Prosthesis Implantation; Drug Delivery Systems; Drug Therapy, Combination; Female; Heparin; Hirudins; Humans; Infusions, Intravenous; Male; Middle Aged; Peptide Fragments; Platelet Glycoprotein GPIIb-IIIa Complex; Postoperative Complications; Recombinant Proteins; Retrospective Studies; Stents; Thrombosis

Topics: Angioplasty, Balloon, Coronary; Anticoagulants; Blood Vessel Prosthesis Implantation; Drug Delivery Systems; Hirudins; Humans; Infusions, Intravenous; Peptide Fragments; Recombinant Proteins; Stents; Thrombosis

Bivalirudin (Angiomax) is increasingly used as a substitute for heparin in a variety of percutaneous coronary interventions. This retrospective, observational study aimed to evaluate the efficacy and safety of bivalirudin compared with heparin as an antithrombotic regimen in patients treated with sirolimus-eluting stents (Cypher) and found that bivalirudin is clinically safe and feasible, with fewer vascular and ischemic complications compared with heparin.

Topics: Anticoagulants; Drug Carriers; Female; Heparin; Hirudins; Humans; Male; Middle Aged; Peptide Fragments; Recombinant Proteins; Retrospective Studies; Sirolimus; Stents; Thrombosis

Current clinical use of heparin as an antithrombotic agent is limited by suboptimal efficacy and safety considerations. Thrombin's central role in thrombosis makes it an attractive target to develop more effective and safer antithrombotic agents. BCH-2763 is a novel, potent (Ki: 0.11 nM), low molecular weight (1.51 kDa), bivalent direct thrombin inhibitor. The antithrombotic efficacy of BCH-2763 in vivo following i.v. bolus plus infusion in rats was compared in arterial and venous thrombosis models with two other bivalent direct thrombin inhibitors, r-hirudin and hirulog, with two catalytic site-directed thrombin inhibitors, inogatran and argatroban, and with heparin. In vivo efficacy was related to inhibition in vitro of fibrin clot formation, thrombin-induced aggregation of rat or human washed platelets and activity of free and plasma clot-bound thrombin. All the direct thrombin inhibitors were effective on both arterial and venous thrombosis at markedly lower fold aPTT increases than heparin. The antithrombotic doses of all inhibitors against venous thrombosis were less than against arterial thrombosis. The rank order of potency based on doses (mg/kg/h) required for full efficacy against arterial thrombosis was BCH-2763 (1.2) > inogatran (1.5) > r-hirudin (1.8) > hirulog (3.3) > argatroban (> 3.0); heparin required a markedly higher dose (5.7). In venous thrombosis the doses required for full efficacy were substantially lower for the bivalent (BCH-2763: 0.12; r-hirudin: 0.12; hirulog: 0.18) than for the catalytic site-directed (inogatran: 0.48; argatroban: 0.90) thrombin inhibitors; the dose required for heparin was 0.19. All the direct thrombin inhibitors caused similar shifts in aPTT at doses required to inhibit arterial thrombosis, but BCH-2763 inhibited venous thrombosis at lower aPTT fold increases. In vivo antithrombotic efficacy of direct thrombin inhibitors correlated with their inhibitory activity in vitro against fibrin clot formation and platelet aggregation. In contrast to heparin, all the direct thrombin inhibitors inhibited plasma clot-bound thrombin, but the relative IC50s did not correlate with their antithrombotic efficacy. In summary, direct thrombin inhibitors are more effective than heparin in inhibiting arterial and venous thrombosis in rats with less aPTT increases. BCH-2763 is effective at lower doses than the other direct thrombin inhibitors and for venous thrombosis at a smaller aPTT increase. BCH-2763 may offer an improved the

Topics: Animals; Anticoagulants; Arginine; Arteries; Glycine; Heparin; Hirudins; Humans; Infusions, Intravenous; Oligopeptides; Peptide Fragments; Pipecolic Acids; Piperidines; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Sulfonamides; Thrombin; Thrombosis; Veins

The importance of thrombin in arterial and venous thrombosis renders thrombin inhibition an important therapeutic target. Identification of novel inhibitors requires an appropriate animal model. We modified a previously reported rat arterial thrombosis model to allow simultaneous assessment of the arterial and venous antithrombotic efficacies of heparin, hirudin, hirulog, a novel thrombin inhibitor H-(N-Me-D-Phe)-Pro-L-trans-4-aminocyclohexyl-Gly-[CO-CO]-NHCH3+ ++ (L-370,518) and the factor Xa inhibitor tick anticoagulant peptide in rabbits. Thrombosis was induced through application of 70% ferric chloride to the femoral artery and jugular vein. Incidence of occlusion, thrombus weight, aPTT and plasma inhibitor concentrations were determined. Heparin was efficacious in preventing arterial and venous occlusive thrombosis but at a dose that profoundly elevated aPTT. On a molar dosing basis, the approximate order of potency of the thrombin and factor Xa inhibitors was similar in artery and vein: hirudin>tick anticoagulant peptide>hirulog> or =L-370,518. Data suggested that compounds tended to be more potent in preventing venous thrombosis than arterial. This thrombin-dependent model is an economical and efficient approach to arterial and venous antithrombotic efficacy screening that eliminates variabilities encountered when multiple model/multiple animal strategies are employed.

Topics: Animals; Antithrombins; Arteries; Arthropod Proteins; Disease Models, Animal; Hirudins; Intercellular Signaling Peptides and Proteins; Peptide Fragments; Peptides; Rabbits; Rats; Recombinant Proteins; Thrombin; Thrombosis; Veins

In the pathogenesis of (recurrent) thrombosis, clot-associated thrombin appears to play an important role. Antithrombin III-independent thrombin inhibitors have been shown to neutralize clot-bound thrombin effectively. We compared the sustained antithrombotic effects and the effects on endogenous fibrinolysis of several of these agents with recombinant tick anticoagulant peptide (rTAP), a selective factor Xa inhibitor, and low-molecular-weight heparin (LMWH) in an experimental venous thrombosis model.. Rabbits received either recombinant hirudin (rHir), Hirulog-1, CVS#995 (a novel direct inhibitor of thrombin), rTAP, LMWH, or saline. The effect on thrombus growth was assessed by measuring the accretion of 125I-labeled fibrinogen onto preformed nonradioactive thrombi, and the effect on endogenous fibrinolysis was assessed by measuring the decline in radioactivity of preformed 125I-labeled thrombi in rabbit jugular veins. All direct thrombin inhibitors induced a sustained antithrombotic effect compared with either LMWH and rTAP. In addition, CVS#995 also further decreased thrombus size after stopping its infusion, which was due to a significant enhancement of endogenous fibrinolysis.. Direct thrombin inhibition by rHir, Hirulog-1, or CVS #995 induces a sustained antithrombotic effect compared with rTAP and LMWH, which is most likely due to inhibition of clot-bound thrombin. CVS#995 was shown to also enhance the extent of endogenous fibrinolysis to a greater degree compared with rHir and might therefore be an interesting new antithrombotic agent for the treatment of venous and arterial thrombosis.

Topics: Animals; Antithrombins; Factor Xa; Factor Xa Inhibitors; Heparin, Low-Molecular-Weight; Hirudin Therapy; Hirudins; Jugular Veins; Peptide Fragments; Rabbits; Recombinant Proteins; Thrombin; Thrombosis

Hirulog, a thrombin-specific inhibitor, has shown efficacy in reducing arterial thrombosis in patients treated with aspirin who require angioplasty or have unstable angina. In this study, the effect of hirulog on reducing deposition of indium 111-labeled platelets was assessed in a surgical model of aspirin-treated rats undergoing carotid endarterectomy.. Animals were randomly assigned to one of five groups: control (no aspirin or hirulog); aspirin alone (10 mg/kg); aspirin plus low-dose hirulog (0.2 mg/kg bolus followed by 0.5 mg/kg/hr); aspirin plus medium-dose hirulog (0.4 mg/kg bolus followed by 1.0 mg/kg/hr); or aspirin plus high-dose hirulog (0.6 mg/kg bolus followed by 1.5 mg/kg/hr). Hirulog was infused before surgery and continued until termination of the experiment 30 minutes after endarterectomy.. Platelet deposition in rats receiving aspirin alone was reduced by 19% +/- 23% SE (p = 0.26) compared with controls. Deposition in aspirin-treated groups receiving low-, medium-, and high-dose hirulog decreased in a dose-dependent manner by 37% +/- 20% (p = 0.048), 44% +/- 19% (p = 0.061), and 56% +/- 13% (p = 0.022), respectively. As the dose of hirulog was increased, the plasma hirulog levels and activated partial thromboplastin time ratios (final:initial) also increased in a dose-dependent manner. The mean plasma hirulog levels ranged from 0.74 +/- 0.08 micrograms/ml in the low-dose hirulog group to 2.55 +/- 0.08 micrograms/ml in the high-dose hirulog group, and the corresponding activated partial thromboplastin time ratios were 1.5 +/- 0.12 (p = 0.001) and 3.3 +/- 0.63 (p = 0.001). Bleeding was easily controlled by local hemostatic measures for all experimental groups.. Hirulog causes significant decrease in 111In-labeled platelet deposition in aspirin-treated rats subjected to microsurgical endarterectomy at doses that allow surgical hemostasis to be easily established.

Topics: Animals; Aspirin; Blood Platelets; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Therapy, Combination; Endarterectomy, Carotid; Hirudin Therapy; Hirudins; Male; Peptide Fragments; Postoperative Complications; Random Allocation; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Thrombin; Thrombosis

Prosthetic vascular grafts become coated with a layer of fibrin that contributes to graft thrombosis and occlusion. We compared the effect of antithrombin III-independent inhibitors of thrombin with heparin for their ability to prevent fibrin accretion onto a model of a vascular graft formed in vitro by coating polyethylene tubing with thrombin bound to a layer of polymerized fibrin. Equivalent antithrombin concentrations of heparin, D-Phe-Pro-Arg CH2Cl (PPACK), recombinant hirudin (r-hirudin), and Hirulog-1 were added to barium chloride-absorbed plasma containing radiolabelled fibrinogen. Whereas, PPACK and r-hirudin persistently inhibited fibrin accretion, the inhibition by heparin was transient. Hirulog-1 had no effect on early fibrin accretion and was actually associated with enhanced accretion at 30 min (control 11.7 +/- 2.0 micrograms fibrin/cm2; Hirulog-1, 18.4 +/- 3.5 micrograms fibrin/cm2, p < 0.001). Both Hirulog-1 and r-hirudin displaced radiolabelled thrombin from the fibrin surface. Whereas hirudin-thrombin complexes are stable, Hirulog-1 produces only transient inhibition of the displaced thrombin thereby accounting for the enhanced fibrin accretion with this anticoagulant. These studies show that the antithrombin III-independent inhibitors, r-hirudin and PPACK, are more effective inhibitors of fibrin accretion onto fibrin-coated polyethylene than heparin or Hirulog-1. In addition, they emphasize the importance of determining the ability of anticoagulants to displace thrombin from fibrin and to form stable thrombin-inhibitor complexes; lack of stability of thrombin-inhibitor complexes must be countered by levels of anticoagulant that are adequate to maintain its effectiveness.

Topics: Amino Acid Chloromethyl Ketones; Amino Acid Sequence; Antithrombin III; Blood Vessel Prosthesis; Fibrin; Heparin; Hirudins; Humans; In Vitro Techniques; Microscopy, Electron, Scanning; Molecular Sequence Data; Peptide Fragments; Polyethylenes; Recombinant Proteins; Surface Properties; Thrombin; Thrombosis