Atrial Fibrillation Clopidogrel Trial With Irbesartan for Prevention of Vascular Events (ACTIVE W)

The purpose of this study is to determine if the combination of Clopidogrel 75mg once daily (od) plus aspirin at 100mg daily (recommended dose) is as effective as oral anticoagulation therapy with a lower risk of bleeding in patients with atrial fibrillation associated with at least one major cardiovascular risk factor.Primary objectives :The combination of clopidogrel plus aspirin compared to adjusted dose (INR between 2.0 and 3.3) oral anticoagulation (a vitamin K antagonist) will result in the same risk of the composite outcome of stroke, non-CNS systemic embolism, myocardial infarction or vascular death in patients with atrial fibrillation.The secondary objective is to establish whether or not aspirin plus clopidogrel has a lower risk of hemorrhage than standard anticoagulation therapy.