Long-term anticoagulation with warfarin is accepted as an effective means of stroke prevention in patients with ischemic stroke due to a high-risk cardiac embolic source, such as cardiac thrombus, prosthetic heart valves, and many patients with atrial fibrillation. The acute management of these patients in terms of the timing and manner of anticoagulation after presentation with cardioembolic stroke is not as clear.
Proponents of early anticoagulation point to the risk of early recurrent stroke from repeat embolization. In the 1980s, the risk of recurrent embolism was felt to be as high as 10% to 20% within the first 2 weeks after ischemic stroke.1 The Cerebral Embolism Study Group2 reported a randomized trial of immediate anticoagulation with intravenous heparin within 48 hours of stroke onset vs no anticoagulation. (Antiplatelet agents were not allowed in the study.) The study was ended prematurely after only 45 patients because of recurrent stroke in 10% of the no-anticoagulation group and 0% in the heparin group.
Wityk RJ. Bridging Anticoagulation After Cardioembolic Stroke. Arch Neurol. 2008;65(9):1157. doi:10.1001/archneur.65.9.1157