Atrial fibrillation, thromboembolism and antithrombotic therapy.
Atrial fibrillation is the commonest sustained disorder of cardiac rhythm and is associated with increased risk of stroke and thromboembolic events. Warfarin (dose-adjusted to a target INR of 2.0-3.0) has been well established to reduce this risk of stroke by 68% (95% CI 50-79%), while aspirin provides a risk reduction of 21% (95% CI 0-38%). Nevertheless, warfarin confers a risk of bleeding and the inconvenience of regular monitoring checks, while aspirin seems effective only for certain low-risk subgroups. Thus there have been strenuous efforts to improve thromboprophylaxis in atrial fibrillation, by using low-intensity anticoagulation regimens, combination antiplatelet therapy and refinement of risk stratification strategies. Attempts at using a low-intensity, fixed-dose warfarin regimen have, however, been disappointing. For now, a strategy of risk stratification should be adopted to identify highest risk patients with atrial fibrillation who would benefit from anticoagulation.
Li-Saw-Hee
F L
FL
University Department of Medicine, City Hospital, Birmingham, UK.
Lip
G Y
GY
D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000627:therapeutic use*; D001241:Aspirin / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000150:complications; D002561:Cerebrovascular Disorders / Q000517:prevention & control*; D006801:Humans; D008875:Middle Aged; D013923:Thromboembolism / Q000209:etiology; D014859:Warfarin / Q000627:therapeutic use*
D000925:Anticoagulants; D014859:Warfarin; D001241:Aspirin