Echocardiography was conducted on 22 patients with macrofocal myocardial infarction in the first 24 hours of the disease and in the three months following. Zones of asynergy of myocardial contraction were found in all patients. Segmental diminution of myocardial contraction was combined with hyperkinesia of areas of the intact heart muscle. Disturbance in regional myocardial contraction was attended with a decrease in functional capacity of the left ventricle. The left ventricular dysfunction in myocardial infarction is to a greater extent determined by the size and character of the asynergy rather than by the localization of infarction. In the period of recovery normalization of contraction was noted in the hypokinetic zones and to a lesser extent in the zones of akinesia. Zones of paradoxical movements of the wall which had developed in the acute period remained 3 months after the onset of the disease.