Prophylactic Anticoagulation Following Acute Myocardial Infarction

Although several large trials have failed to demonstrate unequivocally that anticoagulation decreases mortality following myocardial infarction (MI), anticoagulation has been advocated to prevent embolic cerebrovascular accidents (CVAs). Since CVAs occur during hospitalization in only 1.5% to 3% of MIs, it is not justifiable to anticoagulate all patients after MI because the risk of anticoagulation exceeds the potential benefit. However, a group of patients who are at high risk of developing left ventricular thrombi (LVT) and CVA following MI can be identified. Thirty percent to 40% of patients with transmural anterior MI develop LVT, and early anticoagulation with heparin sodium prevents LVT formation and CVAs in this group. A two-dimensional echocardiogram before hospital discharge allows the identification of patients at risk for later embolization and helps determine the need for anticoagulation with warfarin sodium following hospitalization.