hirudin and Ischemic-Attack--Transient

The direct thrombin inhibitor bivalirudin (BIV) was shown to be superior to unfractionated heparin (UFH) in percutaneous coronary interventions for reducing procedural blood loss. The aim of this study was to compare outcome profiles of BIV and UFH in peripheral endovascular procedures (PEPs) by synthesizing the currently available data.. Following the PRISMA statement, we conducted a comprehensive literature search using Medline, Cochrane CENTRAL, PubMed, EMBASE, CINAHL Google scholar, and clinicaltrials.gov. We recruited randomized, controlled trials and well-conducted observational studies that compared UFH and BIV in PEPs requiring anticoagulation, excluding endovascular cardiac procedures and coronary interventions. Random-effects meta-analyses were conducted to compare the outcome profiles of these two agents.. Thirteen articles containing 14 studies involving a total of 21,057 patients were enrolled. Of these, 2 were randomized controlled trials, 2 were prospective cohort studies, and 10 were retrospective studies. There were no significant differences between BIV and UFH in terms of procedural success rates, major and minor perioperative bleeding, transfusion, perioperative transient ischemic attack, or hemorrhagic strokes. However, compared with UFH, BIV had significantly lower odds ratios (OR) of perioperative mortality (OR, 0.58; 95% confidence interval [CI], 0.40-0.86), major adverse cardiovascular events (OR, 0.65; 95% CI, 0.51-0.83), net adverse clinical events (OR, 0.75; 95% CI, 0.63-0.88), perioperative myocardial infarction (OR, 0.73; 95% CI, 0.55-0.98), major vascular complications (OR, 0.59; 95% CI, 0.39-0.91), and minor vascular complications (OR, 0.58; 95% CI, 0.40-0.84).. Compared with UFH, PEPs using BIV had comparable procedural success rates and odds of perioperative transient ischemic attack and hemorrhagic stroke. However, procedures with BIV had a lower but nonsignificant odds of perioperative bleeding and transfusion. Depending on the procedures conducted, the patients who received BIV will have reduced or comparable odds of perioperative mortality, myocardial infarction, major adverse cardiovascular events, net adverse clinical events, and major and minor vascular complications. Therefore, BIV may be chosen solely as an alternative procedural anticoagulant to UFH for PEPs.

Topics: Anticoagulants; Antithrombins; Endovascular Procedures; Hemorrhage; Heparin; Hirudins; Humans; Ischemic Attack, Transient; Myocardial Infarction; Observational Studies as Topic; Patient Safety; Peptide Fragments; Peripheral Vascular Diseases; Randomized Controlled Trials as Topic; Recombinant Proteins; Risk Assessment; Risk Factors; Stroke; Treatment Outcome

To investigate the clinical implications and mechanisms of spontaneous platelet aggregation (SPA) in man, 150 normal subjects, 22 patient controls and 130 patients with vascular insufficiency were studied. SPA was negative in normal subjects and patient controls whereas it was positive in 36 of 66 (54%) patients with transient ischemic attacks, 6 of 32 (19%) patients with stable angina, 7 of 10 (70%) patients with acute myocardial infarction and 11 of 14 (80%) patients with acute peripheral arterial insufficiency. The SPA was inhibited with aspirin in vivo, and inhibited competitively in vitro by low concentrations of aspirin, 2-chloroadenosine, prostaglandin E1 or apyrase but only by high concentrations of heparin or hirudin. Addition of platelet-poor plasma from patients with positive SPA did not cause normal platelets to aggregate. Treatment of patients who had acute peripheral arterial insufficiency with aspirin and dipyridamole prevented SPA with notable clinical improvement of the ischemic changes.

Topics: Adenosine; Adult; Aged; Angina Pectoris; Apyrase; Arterial Occlusive Diseases; Aspirin; Coronary Disease; Dipyridamole; Heparin; Hirudins; Humans; Ischemic Attack, Transient; Middle Aged; Myocardial Infarction; Platelet Aggregation; Prostaglandins E