In order to evaluate the effects of aortocoronary bypass surgery on left ventricular contraction pattern the ventriculograms of 29 patients were analyzed. For the entire group no changes were found by the evaluation of left ventricular volumes, ejection fraction and circumferential fiber-shortening velocity. The analysis of the regional wall motion (number of asynergic segments, ventricular score, percentual shortening of the hemiaxis) demonstrated positive effects on regional contraction pattern--especially in subgroups. We conclude: 1. a normal left ventricular function associated with successful bypass grafting remains unchanged postoperatively (n = 8); 2. occluded grafts result in a depression of left ventricular function, sometimes accompanied by perioperative myocardial infarctions (n = 13); 3. in a high degree (75%) it is possible to improve or normalize a preoperative depressed ventricular performance in patients without electrocardiographic evidence of a myocardial infarction (n = 12); 4. patients with preoperative myocardial infarctions and successful bypass surgery can have beneficial effects on left ventricular function by an increase in wall motion in additional areas with asynergy without infarction scare (n = 4).