Antithrombotic therapy for stroke prevention in patients with atrial fibrillation

: Atrial fibrillation(AF) is a common arrhythmia that is an important independent risk factor for stroke. The overall risk of stroke in AF patients averages about 5%/y, but with wide variation depending on the presence of coexistent thromboembolic risk factors, which include increasing age, history of hypertension, previous stroke or transient ischemic attack(TIA), and diabetes. AF patients with prior stroke or TIA are at highest risk(about 12%/y). Adjusted-dose warfarin(target INR 2.0-3.0) is highly efficacious for preventing stroke in AF patients, and is safe for selected patients. Aspirin has a modest effect on reducing stroke. Warfarin is recommended for high-risk AF patients who can safely receive it. Aspirin may be indicated for those with a low stroke risk and for those who cannot receive warfarin.