Preventing systemic embolism in patients with abnormal ventricular function.

Clinical trial results support the aggressive use of anticoagulant therapy to prevent systemic embolism in patients with acute myocardial infarction who are at high risk for embolism (e.g., anterior transmural infarction). Other patients at risk for systemic embolism include those with chronic left ventricular aneurysm, chronic dilated cardiomyopathy, and cardiac tumors. The role of antithrombotic therapy in these latter groups is incompletely resolved because of a lack of clinical trials. However, in view of the devastating consequences of systemic embolism, the documented effectiveness of antithrombotic therapy in other high-risk patients and the improved safety of long-term anticoagulant treatment in recent years, it may be prudent to use antithrombotic treatment unless contraindicated.