The characteristics of the left ventricle and coronary arteries associated with left ventricular (LV) thrombus in patients with recent anterior acute myocardial infarction were defined. Of 77 patients studied, 35 (46%) had LV thrombi. The presence of LV thrombus was not correlated to the extent of coronary artery disease. The frequency of LV thrombus progressively increased with groups of increasing wall motion abnormality as determined by the extent of akinesia and dyskinesia (%AD) (%AD 0 to 14, thrombus present in 3 of 16 [19%], %AD 15 to 29, thrombus in 8 of 27 [30%]; %AD greater than or equal to 30%, thrombus in 24 of 34 [71%]; p less than 0.001) and with increasingly severe degrees of early ventricular shape change (normal or mildly abnormal contour, 16% with thrombus; moderately abnormal contour, 36% with thrombus; severely abnormal contour, 70% with thrombus; p less than 0.001). Patients with thrombi had higher diastolic (249 +/- 55 vs 225 +/- 48 ml; p less than 0.05) and systolic (158 +/- 48 vs 120 +/- 45 ml; p less than 0.001) volumes than patients without thrombi, respectively. A stepwise discriminant analysis identified ejection fraction, extent of early shape change and LV end-diastolic pressure as independent correlates of LV thrombus after acute myocardial infarction.