acenocoumarol and Venous-Thromboembolism

Coumarin anticoagulants (acenocoumarol, phenprocoumon, and warfarin) are generally used for the prevention of stroke in patients with atrial fibrillation or for the therapy and prevention of venous thromboembolism. However, the safe use of coumarin anticoagulants is restricted by a narrow therapeutic window and large interindividual dosing variations. Some studies found that the effectiveness and safety of coumarin anticoagulants therapy were increased by pharmacogenetic-guided dosing algorithms, while others found no significant effect of genotype-guided therapy.. Four electronic databases were searched from January 1, 2000, to March 1, 2014, for randomized controlled trials of patients who received coumarin anticoagulants according to genotype-guided dosing algorithms. The primary outcome was the percentage of time that the international normalized ratio (INR) was within the normal range (2.0-3.0). Secondary outcomes included major bleeding events, thromboembolic events, and INR ≥4 events.. Eight studies satisfied the inclusion and exclusion criteria. Genotype-guided dosing of coumarin anticoagulants improved the percentage of time within the therapeutic INR range (95% confidence interval [CI], 0.02-0.28; P = .02; I(2) = 70%). Subgroup analysis was performed after dividing the nongenotype-guided group into a standard-dose group (95% CI, 0.14-0.49; P = .0004; I(2) = 50%) and a clinical variables-guided dosing algorithm group (95% CI, -0.07-0.15; P = .48; I(2) = 34%). There is a statistically significant reduction in numbers of secondary outcomes (INR ≥4 events, major bleeding events, and thromboembolic events; 95% CI, 0.79-1.00; P = .04). Subgroup analysis of secondary outcomes showed no significant difference between genotype-guided dosing and clinical variables-guided dosing (95% CI, 0.84-1.10; P = .57; I(2) = 11%), but genotype-guided dosing reduced secondary outcomes compared with standard dosing (95% CI, 0.62-0.92; P = .006; I(2) = 0%).. This meta-analysis showed that genotype-guided dosing increased the effectiveness and safety of coumarin therapy compared with standard dosing but did not have advantages compared with clinical variables-guided dosing.

Topics: Acenocoumarol; Anticoagulants; Atrial Fibrillation; Dose-Response Relationship, Drug; Genotype; Humans; International Normalized Ratio; Pharmacogenetics; Phenprocoumon; Randomized Controlled Trials as Topic; Stroke; Venous Thromboembolism; Warfarin

Currently, pharmacological thromboprophylaxis is frequently required in patients undergoing surgery, due to the high risk of deep venous thrombosis in the perioperative period. The administration of these anticoagulant agents (in Spain, usually low molecular weight heparins or fondaparinux, and in future, probably also the new oral anticoagulants dabigatran and rivaroxaban) may conflict with regional anesthetic techniques, in which maintaining hemostatic integrity is essential. Therefore, safety protocols have been designed that allow thromboprophylaxis to be administered with optimal effectiveness and anesthetic techniques to be performed with maximal safety; these protocols are based on the drug used, as well as on the dose and time of administration. The present chapter reviews the details related to these issues.

Topics: Acenocoumarol; Administration, Oral; Anesthesia, Conduction; Anticoagulants; Benzimidazoles; Clinical Protocols; Dabigatran; Early Ambulation; Fibrinolytic Agents; Fondaparinux; Heparin; Heparin, Low-Molecular-Weight; Humans; Morpholines; Polysaccharides; Postoperative Complications; Pyridines; Risk Factors; Rivaroxaban; Safety; Surgical Procedures, Operative; Thiophenes; Venous Thromboembolism; Venous Thrombosis

The evaluation and management of patients who sustain recurrent thromboembolic events while taking therapeutic anticoagulation have not been well characterized; moreover, there has been no systematic review or randomized trial focused on treating patients with recurrent deep vein thrombosis (DVT) and pulmonary embolism (PE) during anticoagulant treatment. Therefore, we developed a pilot trial to compare rivaroxaban plus aspirin versus acenocoumarol in patients with recurrent venous thromboembolism despite ongoing anticoagulation with rivaroxaban.. The study was a multicenter, randomized clinical trial. We randomly assigned patients with objectively documented recurrent venous thromboembolism to receive rivaroxaban (20 mg once a day) plus aspirin (300 mg once a day) or an adjusted dose of acenocoumarol. The study was designed to evaluate the incidence of recurrent thromboembolic events (recurrent ipsilateral or contralateral DVT, PE, ischemic stroke, and myocardial infarction) and hemorrhagic events.. A total of 58 patients were randomized: 28 were allocated to the rivaroxaban plus aspirin group and 30 to the acenocoumarol group. After 90 days of follow-up, three recurrent thromboembolic events (primary outcome) occurred in the acenocoumarol group - two DVTs and one ischemic stroke - and zero events in the rivaroxaban plus aspirin group (risk ratio [RR] 0.15; 95 % confidence interval [CI] 0.008-2.83; P = 0.20). Minor bleeding occurred in five patients in the acenocoumarol group and zero in the rivaroxaban plus aspirin group (RR 0.09; 95 % CI 0.005-1.68; p = 0.10). There was one non-fatal gastrointestinal major bleed in the rivaroxaban plus aspirin group.. In this pilot study, there were no significant differences in any outcome assessed; however, recurrent thromboembolic events and minor bleeding events occurred numerically less frequently in the rivaroxaban plus aspirin group. These data suggest the need to carry out more extensive randomized studies with sufficient statistical power to clarify these results.

Topics: Acenocoumarol; Anticoagulants; Aspirin; Hemorrhage; Humans; Ischemic Stroke; Pilot Projects; Pulmonary Embolism; Rivaroxaban; Venous Thromboembolism; Venous Thrombosis

Unfavorable fibrin clot features have been observed in patients with venous thromboembolism (VTE). We investigated whether rivaroxaban, a direct factor Xa inhibitor, and vitamin K antagonists (VKAs) can improve plasma clot viscoelastic properties. We studied four age- and sex-matched groups: 25 healthy controls, 15 VTE patients taking rivaroxaban 20 mg/day (blood concentration, 145 (67 - 217) ng/ml), 15 VTE patients taking VKA (INR: 2 - 3), and 15 VTE patients who stopped oral anticoagulant therapy (OAT). Using a hybrid rheometier the storage (G') and loss (G") moduli were evaluated in citrated plasma after addition of 5 pmol/l tissue factor. Fiber thickness within clots was assessed using scanning electron microscopy. Higher G' but not G" was observed for VTE patients taking rivaroxaban (+34%; post hoc, P = 0.029) compared to controls. As reflected by lower G' and G", patients taking rivaroxaban (-19% and -30%; post hoc, P = 0.0013 and P < 0.0001, respectively) formed less stiff and viscous clots compared to VTE patients after OAT withdrawal, also after adjustment for fibrinogen. VTE patients treated with rivaroxaban and VKA had similar clot viscoelastic properties (post hoc, P = 0.85 for G' and P = 0.29 for G"). G' and G" correlated with plasma rivaroxaban concentrations (r = -0.67, P = 0.005 and r = -0.59, P = 0.021, respectively), and the time from the last dose of rivaroxaban intake (r = 0.59, P = 0.02 and r = 0.58, P = 0.022, respectively). G' and G" showed no association with INR in patients on VKAs. G' or G" were not associated with fibrin diameter on scanning electron microscopy images in either group. Our preliminary study shows that both rivaroxaban and VKA improve clot viscoelastic properties in VTE patients, which might contribute to their antithrombotic effects. G' and G" may reflect specific clot physical features, beyond key plasma clot characteristics, which highlights benefits from comprehensive plasma clot analysis in patients with thrombotic diseases.

Topics: Acenocoumarol; Adult; Anticoagulants; Elasticity; Factor Xa Inhibitors; Female; Fibrin; Humans; Male; Middle Aged; Rivaroxaban; Thrombosis; Venous Thromboembolism; Viscosity; Vitamin K; Warfarin

Venous thromboembolism (VTE) is a common and serious complication in patients with cancer; treatment guidelines recommend extended therapy of ≥6 months with low-molecular-weight heparin (LMWH) for treatment and prevention of recurrent VTE (rVTE) in this population. This post hoc analysis used data from the CLOT study-a phase III, randomized, open-label, controlled study (N = 676)-to compare the efficacy and safety of dalteparin, a LMWH, versus vitamin K antagonist (VKA) for prevention of rVTE in patients with cancer and renal impairment (creatinine clearance <60 ml/min). Overall, 162/676 (24 %) patients had renal impairment at baseline. Patients received subcutaneous dalteparin 200 IU/kg once daily during month 1, followed by 150 IU/kg once daily for months 2-6; or VKA once daily for 6 months, with initial overlapping subcutaneous dalteparin 200 IU/kg once daily for ≥5 days until international normalized ratio was 2.0-3.0 for 2 consecutive days. Endpoints included the rates of rVTE (primary) and bleeding events. Overall, fewer dalteparin-treated patients (2/74 [2.7 %]) experienced ≥1 adjudicated symptomatic rVTE compared with VKA-treated patients (15/88 [17.0 %]; hazard ratio = 0.15 [95 % confidence interval 0.03-0.65]; p = 0.01). Bleeding event rates for both treatments were similar (p = 0.47). In summary, compared with VKA, dalteparin significantly reduced risk of rVTE in patients with cancer and renal impairment (p = 0.01) while exhibiting a comparable safety profile. This analysis supports dosing patients with renal impairment in accordance with patients with normal renal function; however, anti-Xa monitoring could be considered to further support safety in selected patients, particularly those with very severe renal impairment.

Topics: Acenocoumarol; Administration, Oral; Adult; Aged; Aged, 80 and over; Anticoagulants; Dalteparin; Female; Humans; Kidney Diseases; Male; Middle Aged; Neoplasms; Venous Thromboembolism; Vitamin K; Warfarin

Vitamin K antagonists (VKA) are used to prevent recurrent disease in patients with venous thromboembolism (VTE). Their efficacy and safety depend on individual time in therapeutic range (iTTR) and variability of International Normalised Ratios (INR). We aimed to identify independent predictors of poor VKA control > 28 days. In a prospective cohort of 3825 VTE patients, separate logistic regression analyses were performed to identify predictors of low iTTR (first quartile) and instability (iTTR median). Subsequently, the association between these predictors and clinical outcomes was investigated. Weight < 50 kg (odds ratio [OR]=1.89; 95 % confidence interval [CI] 1.03-3.49), active cancer at baseline (OR=1.52; CI1.05-2.19), secondary VTE (OR=1.42; CI1.20-1.68), and INR < 2.0 at stop of double therapy (OR=1.35; CI1.09-1.67) were independent predictors of low iTTR. The first two were also predictive for instability (OR=1.96; CI1.06-3.63 and OR=1.95; CI1.36-2.80, respectively). ORs of early (≤ 28 days) low iTTR and instability depended on VKA type. In acenocoumarol users, early low iTTR was an independent predictor of subsequent low iTTR (OR=1.92; CI1.31-2.80) and instability (OR=1.55; CI1.07-2.23). In warfarin users, early low iTTR (OR=1.36; CI1.09-1.69) and instability (OR=1.25; CI1.01-1.55) were additionally predictive for low iTTR, but only the latter was predictive for instability (OR=1.91; CI1.57-2.32). Many predictors of VKA control also predicted premature discontinuation, but only region was prognostic for clinical outcome. In conclusion, we identified several independent predictors of low iTTR and instability > 28 days, which showed some similarities but did not fully overlap. Early VKA control was of additional value for prediction of both, but had to be interpreted in the context of VKA type.

Topics: Acenocoumarol; Administration, Oral; Aged; Anticoagulants; Drug Therapy, Combination; Enoxaparin; Female; Hemorrhage; Humans; International Normalized Ratio; Male; Middle Aged; Neoplasms; Prognosis; Recurrence; Risk Factors; Thrombophilia; Treatment Outcome; Venous Thromboembolism; Vitamin K; Warfarin

Hemorrhagic events are frequent in patients on treatment with antivitamin-K oral anticoagulants due to their narrow therapeutic margin. Studies performed with acenocoumarol have shown the relationship between demographic, clinical and genotypic variants and the response to these drugs. Once the influence of these genetic and clinical factors on the dose of acenocoumarol needed to maintain a stable international normalized ratio (INR) has been demonstrated, new strategies need to be developed to predict the appropriate doses of this drug. Several pharmacogenetic algorithms have been developed for warfarin, but only three have been developed for acenocoumarol. After the development of a pharmacogenetic algorithm, the obvious next step is to demonstrate its effectiveness and utility by means of a randomized controlled trial. The aim of this study is to evaluate the effectiveness and efficiency of an acenocoumarol dosing algorithm developed by our group which includes demographic, clinical and pharmacogenetic variables (VKORC1, CYP2C9, CYP4F2 and ApoE) in patients with venous thromboembolism (VTE).. This is a multicenter, single blind, randomized controlled clinical trial. The protocol has been approved by La Paz University Hospital Research Ethics Committee and by the Spanish Drug Agency. Two hundred and forty patients with VTE in which oral anticoagulant therapy is indicated will be included. Randomization (case/control 1:1) will be stratified by center. Acenocoumarol dose in the control group will be scheduled and adjusted following common clinical practice; in the experimental arm dosing will be following an individualized algorithm developed and validated by our group. Patients will be followed for three months. The main endpoints are: 1) Percentage of patients with INR within the therapeutic range on day seven after initiation of oral anticoagulant therapy; 2) Time from the start of oral anticoagulant treatment to achievement of a stable INR within the therapeutic range; 3) Number of INR determinations within the therapeutic range in the first six weeks of treatment.. To date, there are no clinical trials comparing pharmacogenetic acenocoumarol dosing algorithm versus routine clinical practice in VTE. Implementation of this pharmacogenetic algorithm in the clinical practice routine could reduce side effects and improve patient safety.. Eudra CT. Identifier: 2009-016643-18.

Topics: Acenocoumarol; Administration, Oral; Algorithms; Anticoagulants; Blood Coagulation; Clinical Protocols; Drug Dosage Calculations; Drug Monitoring; Hemorrhage; Humans; International Normalized Ratio; Pharmacogenetics; Research Design; Single-Blind Method; Spain; Time Factors; Treatment Outcome; Venous Thromboembolism

The safest duration of anticoagulation after idiopathic deep vein thrombosis (DVT) is unknown. We conducted a prospective study to assess the optimal duration of vitamin K antagonist (VKA) therapy considering the risk of recurrence of thrombosis according to residual vein thrombosis (RVT). Patients with a first unprovoked DVT were evaluated for the presence of RVT after 3 months of VKA administration; those without RVT suspended VKA, while those with RVT continued oral anticoagulation for up to 2 years. Recurrent thrombosis and/or bleeding events were recorded during treatment (RVT group) and 1 year after VKA withdrawal (both groups). Among 409 patients evaluated for unprovoked DVT, 33.2% (136 of 409 patients) did not have RVT and VKA was stopped. The remaining 273 (66.8%) patients with RVT received anticoagulants for an additional 21 months; during this period of treatment, recurrent venous thromboembolism and major bleeding occurred in 4.7% and 1.1% of patients, respectively. After VKA suspension, the rates of recurrent thrombotic events were 1.4% and 10.4% in the no-RVT and RVT groups, respectively (relative risk = 7.4; 95% confidence interval = 4.9-9.9). These results indicate that in patients without RVT, a short period of treatment with a VKA is sufficient; in those with persistent RVT, treatment extended to 2 years substantially reduces, but does not eliminate, the risk of recurrent thrombosis.

Topics: Acenocoumarol; Adult; Aged; Anticoagulants; Drug Administration Schedule; Female; Hemorrhage; Humans; Lower Extremity; Male; Middle Aged; Prospective Studies; Recurrence; Risk Factors; Ultrasonography; Venous Thromboembolism; Venous Thrombosis; Vitamin K; Warfarin

The objective of the present study was to evaluate the efficacy, safety and healthcare resource utilization of long-term treatment with tinzaparin in symptomatic patients with acute pulmonary embolism as compared to standard therapy. In this open-label trial, 102 patients with objectively confirmed pulmonary embolism were randomized to receive, after initial treatment with tinzaparin, either tinzaparin (175 IU/kg/day) or international normalized ratio-adjusted acenocoumarol for 6 months. Clinical endpoints were assessed during the 6 months of treatment. A pharmacoeconomic analysis was carried out to evaluate the cost of the long-term treatment with tinzaparin in comparison with the standard one. In an intention-to-treat analysis, one of 52 patients developed recurrent venous thromboembolism in the tinzaparin group compared with none of the 50 patients in the acenocoumarol group. One patient in each group had a major haemorrhagic complication. Six patients in the acenocoumarol group had minor bleeding compared with none in the tinzaparin group (P = 0.027). Median hospital length of stay was shorter in the tinzaparin group compared to the acenocoumarol group (7 versus 9 days; P = 0.014). When all the direct and indirect cost components were combined for the entire population, we found a slight, nonstatistically significant (mean difference €345; 95% CI 1382-2071; P = 0.69) reduction in total cost with tinzaparin. Symptomatic acute pulmonary embolism treatment with full therapeutic doses of tinzaparin for 6 months is a feasible alternative to conventional treatment with vitamin K antagonists.

Topics: Acenocoumarol; Adult; Aged; Aged, 80 and over; Anticoagulants; Female; Fibrinolytic Agents; Heparin, Low-Molecular-Weight; Humans; Male; Middle Aged; Pulmonary Embolism; Tinzaparin; Treatment Outcome; Venous Thromboembolism; Young Adult

Rivaroxaban, an oral factor Xa inhibitor, may provide a simple, fixed-dose regimen for treating acute deep-vein thrombosis (DVT) and for continued treatment, without the need for laboratory monitoring.. We conducted an open-label, randomized, event-driven, noninferiority study that compared oral rivaroxaban alone (15 mg twice daily for 3 weeks, followed by 20 mg once daily) with subcutaneous enoxaparin followed by a vitamin K antagonist (either warfarin or acenocoumarol) for 3, 6, or 12 months in patients with acute, symptomatic DVT. In parallel, we carried out a double-blind, randomized, event-driven superiority study that compared rivaroxaban alone (20 mg once daily) with placebo for an additional 6 or 12 months in patients who had completed 6 to 12 months of treatment for venous thromboembolism. The primary efficacy outcome for both studies was recurrent venous thromboembolism. The principal safety outcome was major bleeding or clinically relevant nonmajor bleeding in the initial-treatment study and major bleeding in the continued-treatment study.. The study of rivaroxaban for acute DVT included 3449 patients: 1731 given rivaroxaban and 1718 given enoxaparin plus a vitamin K antagonist. Rivaroxaban had noninferior efficacy with respect to the primary outcome (36 events [2.1%], vs. 51 events with enoxaparin-vitamin K antagonist [3.0%]; hazard ratio, 0.68; 95% confidence interval [CI], 0.44 to 1.04; P<0.001). The principal safety outcome occurred in 8.1% of the patients in each group. In the continued-treatment study, which included 602 patients in the rivaroxaban group and 594 in the placebo group, rivaroxaban had superior efficacy (8 events [1.3%], vs. 42 with placebo [7.1%]; hazard ratio, 0.18; 95% CI, 0.09 to 0.39; P<0.001). Four patients in the rivaroxaban group had nonfatal major bleeding (0.7%), versus none in the placebo group (P=0.11).. Rivaroxaban offers a simple, single-drug approach to the short-term and continued treatment of venous thrombosis that may improve the benefit-to-risk profile of anticoagulation. (Funded by Bayer Schering Pharma and Ortho-McNeil; ClinicalTrials.gov numbers, NCT00440193 and NCT00439725.).

Topics: Acenocoumarol; Acute Disease; Administration, Oral; Aged; Anticoagulants; Double-Blind Method; Enoxaparin; Factor Xa Inhibitors; Female; Hemorrhage; Humans; Injections, Subcutaneous; Intention to Treat Analysis; Kaplan-Meier Estimate; Male; Middle Aged; Morpholines; Pulmonary Embolism; Rivaroxaban; Thiophenes; Venous Thromboembolism; Venous Thrombosis; Vitamin K; Warfarin

Effective prevention of thromboembolism is essential for patients with mechanical prosthetic heart valves. For this group of patients, vitamin K antagonists (VKAs) remain the drug group of choice despite the widespread use of new anticoagulants in other diseases. As a consequence, warfarin resistance remains a serious challenge for physicians. The current report describes a 65-year-old male patient that had a mechanical prosthetic aortic valve implanted due to severe aortic insufficiency after infective endocarditis. Despite consistent increases in his warfarin dose, the level of international normalized ratio (INR) remained very low. The patient was considered to have warfarin resistance. Warfarin was successfully replaced by another VKA, acenocoumarol, which resulted in a stable INR observed over 1 year of follow-up. Achieving the target INR in patients with mechanical prosthetic heart valves using VKAs is the main goal of thromboprophylaxis. Although the genetic changes that cause warfarin resistance are understood, the options to overcome these pharmacogenetic issues remain limited. Based on the success with this current patient, physicians with similar patients with warfarin resistance might wish to consider replacing warfarin with acenocoumarol.

Topics: Acenocoumarol; Aged; Anticoagulants; Fibrinolytic Agents; Heart Valve Prosthesis; Humans; International Normalized Ratio; Male; Metabolism, Inborn Errors; Venous Thromboembolism; Warfarin

Vitamin K antagonists are indicated for the thromboprophylaxis in patients with mechanical prosthetic heart valves (MPHV). However, it is unclear whether some differences between acenocoumarol and warfarin in terms of anticoagulation quality do exist. We included 2111 MPHV patients included in the nationwide PLECTRUM registry. We evaluated anticoagulation quality by the time in therapeutic range (TiTR). Factors associated with acenocoumarol use and with low TiTR were investigated by multivariable logistic regression analysis. Mean age was 56.8 ± 12.3 years; 44.6% of patients were women and 395 patients were on acenocoumarol. A multivariable logistic regression analysis showed that patients on acenocoumarol had more comorbidities (i.e., ≥3, odds ratio (OR) 1.443, 95% confidence interval (CI) 1.081-1.927,

Topics: Acenocoumarol; Aged; Anticoagulants; Blood Coagulation; Female; Heart Valve Diseases; Heart Valve Prosthesis; Humans; Male; Middle Aged; Retrospective Studies; Venous Thromboembolism; Warfarin

Treatment with vitamin K antagonists (VKA) requires a high proportion of time in the therapeutic range (TTR) and a low international normalised ratio (INR) variability to be maximally safe and effective. Switching from short-acting acenocoumarol to long-acting phenprocoumon could improve VKA control.. We assessed whether switching from acenocoumarol to phenprocoumon improves the time in the therapeutic range (TTR) and INR variability.. In a retrospective cohort with data on 236,957 patients-years of VKA management from two first-line anticoagulation clinics in the Netherlands, we identified 124 patients in target range 2-3, 269 patients in target range 2-3.5 and 98 patients in target range 2.5-3.5 who switched from acenocoumarol to phenprocoumon. They were matched in a 1:2 ratio to non-switching controls using propensity score matching. Over the first 180 days after a switch, switchers' TTR declined 5 (95% CI 1 to 10), 10 (95% CI 7 to 13) and 5 (95% CI 0 to 11) percentage points relative to non-switchers, in target ranges 2-3, 2-3.5 and 2.5-3.5. Anticoagulation was more often supra-therapeutic in switchers, and switchers had a higher INR variability. In the following 180 days, TTR in switchers became 1 (95% CI -4 to 6), 4 (95% CI 0 to 7) and 6 (95% CI 1 to 12) percentage points better than in non-switchers. Switchers' INRs were much more stable than non-switchers'.. Eventually, a switch from acenocoumarol to phenprocoumon leads to a higher TTR and a lower INR variability. However, this is preceded by a transition period with opposite effects. An improved conversion algorithm could possibly shorten the transition period. Until then, physicians and patients should decide whether switching is worth the increased risk during the transition phase.

Topics: Acenocoumarol; Administration, Oral; Aged; Aged, 80 and over; Anticoagulants; Cohort Studies; Female; Humans; International Normalized Ratio; Male; Middle Aged; Phenprocoumon; Retrospective Studies; Risk; Treatment Outcome; Venous Thromboembolism; Vitamin K

Infection caused by SARS-CoV-2 (COVID-19) is associated with an increased risk of thromboembolic disease. So-me authors recommend anticoagulation at therapeutic doses for, at least, the most severely ill patients; this practice is not free of risks, which is why only thromboembolic prophylaxis is recommended by other consensuses. In the case of previously anticoagulated patients, changing the oral anticoagulant for a low molecular weight heparin (LMWH) is generally recommended. We present the cases of two patients admitted due to COVID-19, without serious clinical data, in whom anticoagulation (acenocoumarol and rivaroxaban, respectively) was replaced by LMWH at therapeutic doses, both presenting abdominal bleeding. This type of bleeding is an infrequent complication in anticoagulated patients, but the concurrence of two cases in a short period of time in the context of the COVID-19 pandemic leads us to consider that there is not yet any clear evidence on therapeutic anticoagulation in SARS-CoV-2 infection.

Topics: Abdomen; Acenocoumarol; Aged, 80 and over; Anticoagulants; Betacoronavirus; Coronavirus Infections; COVID-19; Female; Hematoma; Heparin, Low-Molecular-Weight; Humans; Pandemics; Pneumonia, Viral; Rivaroxaban; SARS-CoV-2; Venous Thromboembolism

Single nucleotide polymorphisms (SNP) in genes encoding proteins involved in metabolism and action of vitamin K antagonists (VKA) affect anticoagulation stability. We investigated how those polymorphisms influence bleeding rates in patients following venous thromboembolism (VTE).. In 324 patients following unprovoked VTE, 143 (44%) on warfarin and 181 (56%) on acenocoumarol, we recorded bleeds within the preceding 24 months. We assessed eight SNP, including those in cytochrome P450 isoform 2C9 (CYP2C9) and isoform 4F2 (CYP4F2), vitamin K epoxide reductase complex subunit 1 (VKORC1), gamma-glutamyl carboxylase (GGCX), apolipoprotein E (APOE) and multidrug resistance gene 1 (MDR1).. Within 48 months before enrolment, bleeding events occurred in 80 (25%) patients, including 14 (4%) major bleeds. Patients with bleeds had 16.2% lower median time in therapeutic range (TTR) and were more often carriers of CYP2C9*3 variant (26 [33%] vs. 19 [8%], p < 0.001) compared with the remainder. Bleeding occurred more frequently in patients with ≥4 SNP compared with the remainder (27 [34%] vs. 47 [19%], p = 0.009) with no intergroup differences of TTR. Number of SNP was one of the predictors of any bleeding. The regression model for major bleeding including factors such as CYP2C9*3 c. 1075 C, VKORC1 c. -1639 A and APOE c. 388 C showed good predictive ability (area under the curve - 0.79).. In VTE patients on the maintenance treatment with VKA, bleeding episodes are associated with CYP2C9 gene variations and increased number of SNP of genes involved in the action and metabolism of VKA.

Topics: Acenocoumarol; Adult; Anticoagulants; Apolipoproteins E; Cytochrome P-450 CYP2C9; Female; Gene Frequency; Genetic Predisposition to Disease; Hemorrhage; Humans; Male; Middle Aged; Phenotype; Polymorphism, Single Nucleotide; Risk Factors; Venous Thromboembolism; Vitamin K; Vitamin K Epoxide Reductases; Warfarin

The SAMe-TT. We included all consecutive patients with VTE treated with VKA for >90days. We collected all variables included in the score (female sex, age<60years, medical history [>2 comorbidities], treatment [interacting drugs: e.g. amiodarone], tobacco [doubled], race [doubled]) and analyzed the relationship between the SAMe-TT. 135 patients were treated with VKA for >90days, with a median TTR 65%. No differences in INR controls within range were found between patients with score 0-1 vs ≥2 (64.7±19.5% vs 66.0±20.5%, p=0.728). No differences were found in INR controls above (21.5±18.1% vs 21.2±21.3%, p=0.605) or below (3.9±14% vs 2.9±15.9%, p=0.517) the therapeutic range.

Topics: Acenocoumarol; Algorithms; Anticoagulants; Blood Coagulation; Cohort Studies; Female; Humans; International Normalized Ratio; Male; Middle Aged; Prospective Studies; ROC Curve; Venous Thromboembolism; Vitamin K; Warfarin

Vitamin K antagonists (VKAs) remain as the most prescribed drug for treatment and prevention of thrombotic disorders in many countries, despite the recent approval of the new oral anticoagulants (NOACs). Although effectiveness and safety of VKAs are tightly associated to maintaining the patient within the international normalised ratio (INR) therapeutic range (TWR), they have been likened to NOACs when patients are in good INR control (≥66% of TWR). Therefore, assessing the safety of patients should be a priority in the selection of the anticoagulation therapy. The aim of this study was to evaluate the association between CYP2C9*2, CYP2C9*3, VKORC1, CYP4F2*3, ABCB1 C3435T, APOE, CYP2C19*2 and CYP2C19*17 gene polymorphisms and treatment safety in 128 patients diagnosed with atrial fibrillation or venous thromboembolism during the initial first seven months of acenocoumarol therapy. After the first month, VKORC1-T-allele and APOE-E3/E3 genotype were independently associated to higher time above therapeutic range (TAR) and lower time below the therapeutic range (TBR). After seven months, VKORC1 T-allele predicted higher TAR, and was also associated to increased INR>4, particularly the TT-genotype (odds ratio [OR]: 32; 95% confidence interval [CI95%]: 6-175; p=810⁻⁵). C-alleles for CYP2C9*3 (OR: 5.5; CI95%: 1.8-17; p=0.003) and ABCB1 (OR: 8.9;CI95%: 1.1-70; p=0.039) independently influenced on INR>6 . Patients VKORC1-TT/ABCB1-C remained 26.8% [19.7-38.9] TAR, with associated relative risk (RR) for INR>4 1.8 higher (CI95%: 1.2-2.5; p=0.015). Patients VKORC1-TT also presented the highest risk of bleeding events (RR: 3.5;CI95%: 1.4-8.4; p=0,010). In conclusion, VKORC1, CYP2C9*3, APOE and ABCB1 genotypes should be considered in prevention of overanticoagulation and bleeding events in the initiation of acenocoumarol therapy.

Topics: Acenocoumarol; Aged; Aged, 80 and over; Alleles; Anticoagulants; Apolipoproteins E; ATP Binding Cassette Transporter, Subfamily B; Atrial Fibrillation; Cytochrome P-450 CYP2C19; Cytochrome P-450 CYP2C9; Cytochrome P-450 Enzyme System; Cytochrome P450 Family 4; Female; Follow-Up Studies; Genetic Association Studies; Genotype; Hemorrhage; Humans; Male; Middle Aged; Pharmacogenetics; Polymorphism, Genetic; Venous Thromboembolism; Vitamin K Epoxide Reductases

To develop an acenocoumarol (ACN) dosing algorithm for patients with atrial fibrillation or venous thromboembolism, considering the influence on the stable ACN dose of clinical factors and gene polymorphisms, including CYP2C9*2/*3, VKORC1, CYP4F2*3, ABCB1, APOE, CYP2C19*2/*17, and GGCX.. A retrospective observational study was carried out to obtain clinical and pharmacogenetic dose algorithms by multiple linear regression of results in a cohort of 134 patients under treatment with a stable ACN dose for atrial fibrillation or venous thromboembolism and to test them in an independent validation cohort of 30 patients.The pharmacogenetic dosing algorithm included CYP2C9, VKORC1, and APOE, which explained 56.6% of the variability in the stable ACN dose. Lower deviation from the stable dose and increased accuracy were shown by the pharmacogenetic algorithm, which correctly classified 67% of patients with a deviation of up to 20%.. The variability in the stable ACN dose was better explained by a pharmacogenetic algorithm including clinical and genetic factors (CYP2C9, VKORC1, and APOE) than by a clinical algorithm, providing a more accurate dosage prediction.

Topics: Acenocoumarol; Aged; Aged, 80 and over; Algorithms; Anticoagulants; Apolipoproteins E; Atrial Fibrillation; Cytochrome P-450 CYP2C9; Drug Dosage Calculations; Female; Genetic Variation; Humans; Male; Middle Aged; Pharmacogenetics; Retrospective Studies; Venous Thromboembolism; Vitamin K Epoxide Reductases

Drug reaction with eosinophlia and systemic symptoms (DRESS) syndrome describes a severe medication-induced adverse reaction, which shows skin, blood and solid-organ features. Up to 50 drugs have been described to cause DRESS. The main responsible drugs are carbamazepine and allopurinol. There are no previous reports associated with acenocoumarol. A 85-year-old white male, who was treated with acenocoumarol for the prevention of venous thromboembolism due to atrial fibrillation, presented 6 weeks later a maculopapular exanthema of the trunk and limbs as well as purple lesions and blisters on distal parts of his legs. Elevated creatinine, glucose, urea, International Normalized Ratio, gamma-glutamyl-transpeptidase (GGT) and eosinophilia levels were observed. Acenocoumarol was removed and enoxaparine, systemic corticosteroids, antihistamines were used as treatment with a favorable clinical evolution: 1 month later, the skin lesions had disappeared and laboratory parameters were normalized. Patch tests with warfarin and dabigatran were carried out. Two simple-blind, placebo-controlled oral challenges with warfarin and dabigatran were performed. Patch tests were negative, and single-blind, placebo-controlled oral challenges with warfarin and dabigatran were achieved without immediate or delayed reactions. We firstly describe a DRESS syndrome induced by acenocoumarol. Patch test was useful to assess alternative therapies. Tolerance to other anticoagulants (warfarin and dabigatran) was demonstrated.

Topics: Acenocoumarol; Aged, 80 and over; Anticoagulants; Benzimidazoles; beta-Alanine; Dabigatran; Drug Eruptions; Eosinophilia; Exanthema; Humans; Male; Venous Thromboembolism; Warfarin

Topics: 4-Hydroxycoumarins; Acenocoumarol; Anticoagulants; Contraindications; Dose-Response Relationship, Drug; Drug Administration Routes; Drug Interactions; Drug Utilization; Drugs, Investigational; Heparin; Humans; Indenes; Treatment Outcome; Venous Thromboembolism; Vitamin K

For the last 60 years, heparin and vitamin K antagonists have been the cornerstone of anticoagulation. Nowadays, the new anticoagulants, such as dabigatran, rivaroxaban and apixaban, show potential advantages over classical treatments. These agents inhibit specific coagulation factors and are administered orally at fixed doses. Furthermore, heparin and vitamin K antagonists have a fast onset of action, short-duration and predictable therapeutic effects. No interactions with foods have been described, although some drug-drug interactions have been reported. At the moment, no antidotes are available. However, due to the short half-life of these agents, antidotes are less essential. The new anticoagulants are at least as effective and safe as traditional treatments in the prevention of venous thromboembolism after orthopedic surgery, as well as in the prevention of stroke and systemic embolism in non-valvular atrial fibrillation. Dabigatran and rivaroxaban have also been shown to be effective in the treatment of acute venous thromboembolism. Due to their properties, these drugs could gradually replace heparin and especially vitamin K antagonists. Hopefully, many of our patients will be able to discontinue classical anticoagulant treatment and others will never begin it.

Topics: Acenocoumarol; Administration, Oral; Anticoagulants; Atrial Fibrillation; Benzimidazoles; beta-Alanine; Dabigatran; Heparin; Humans; Morpholines; Pyrazoles; Pyridones; Rivaroxaban; Stroke; Thiophenes; Treatment Outcome; Venous Thromboembolism; Warfarin

International normalized ratio (INR) is used to monitor chronic oral anticoagulant (OA) treatment; however, it is poorly understood how this simple test reflects in vivo hemostatic reactions, culminating in thrombin generation and clot formation. We studied the process of thrombin generation using an ex vivo model, where thrombin-antithrombin (TAT) complexes are measured in blood emerging from standardized skin incisions in 55 patients (35 with venous thromboembolism [VTE] and 20 with sustained atrial fibrillation [AF]) treated with acenocoumarol (INR 2.0-3.0). In addition, in venous blood, we measured the activity of factor VIII (FVIII) and vitamin K-dependent coagulation proteins. Chronic anticoagulation led to significant reductions in maximum TAT concentrations as compared to 35 healthy controls, in maximum TAT generation rates, and in mean amount of thrombin generated. Parameters of thrombin generation did not correlate with INR or any coagulation factor measured. International normalized ratio was significantly and independently affected by the decrease in the activity of all vitamin K-dependent coagulation proteins. The strongest influence was shown for FVII. Factor VIII activity was increased in all patients studied independently of the duration of anticoagulation and did not change over time. In conclusion, in patients with VTE and AF on OA, there is no correlation between INR values and parameters of ex vivo thrombin generation. This may indicate an important role of protein C (PC) system and possibly other endothelium-dependent mechanisms in controlling hemostasis. Increased FVIII activity in patients with VTE and AF does not change significantly during anticoagulation and is probably related to the pretreatment prothrombotic state.

Topics: Acenocoumarol; Anticoagulants; Antithrombins; Atrial Fibrillation; Case-Control Studies; Factor VIII; Female; Humans; International Normalized Ratio; Long-Term Care; Male; Middle Aged; Prothrombin; Thrombin; Venous Thromboembolism

Pulmonary embolism is an insidious life-threatening condition. Its diagnosis represents a challenging topic in daily clinical practice since the recognition and the appropriate management of the condition can lead to the decrease of potentially fatal consequences. We present a clinical case which highlights the necessity for an increased level of 'surveillance' from the involved physicians since features of thromboembolic events may be elusive or vague.

Topics: Acenocoumarol; Adult; Anticoagulants; Drainage; Heparin, Low-Molecular-Weight; Humans; Male; Pleural Effusion; Pulmonary Embolism; Tomography, Spiral Computed; Venous Thromboembolism