Anti-thrombotic therapy for non-rheumatic atrial fibrillation.

Recent randomized trials of antithrombotic therapy in non-rheumatic atrial fibrillation have helped to clarify the benefits of warfarin and aspirin. Low-risk patients (normotensives aged < 60 with normal left ventricular function) have a small risk of thromboembolic events and are unlikely to benefit significantly from anticoagulants, but may benefit from aspirin with little increase in risk of bleeding. High-risk patients (> 75 years, impaired left ventricular function, previous thromboembolism and/or associated conditions such as hypertension and diabetes mellitus) have an increased risk of thromboembolism, and benefit from long-term anticoagulant therapy to a greater degree than with aspirin, although at a risk of increased bleeding complications.