Incidence of left-ventricular thrombosis after acute transmural myocardial infarction. Serial evaluation by two-dimensional echocardiography.

To study the incidence of left-ventricular thrombosis after transmural myocardial infarction, we performed serial two-dimensional echocardiography in 70 consecutive patients. Thirty-five patients had inferior-wall infarction: none had a left-ventricular thrombus. The other 35 had anterior-wall infarction: 12 had left-ventricular thrombi. Thrombi were diagnosed an average of five days after the infarction (range, one to 11 days). All patients with left-ventricular thrombi had severe apical-wall-motion abnormalities (akinesis or dyskinesis). Twenty-six of the 35 patients with anterior infarctions had apical akinesis or dyskinesis on echocardiography; left-ventricular thrombi developed in 12 of these 26 (46 per cent). We conclude that patients with severe apical-wall-motion abnormalities during acute transmural anterior myocardial infarction are at high risk for left-ventricular thrombosis. This high-risk group can be identified before the development of left-ventricular thrombi. Patients with inferior infarction or anterior infarction without a severe apical-wall-motion abnormality are at low risk.