Since 1978, there have been sporadic reports of coronary artery embolism caused by cardiac catheterization, percutaneous transluminal coronary angioplasty, and other invasive procedures. To determine whether coronary artery embolism has increased with the wider application of such procedures, we searched for patients with coronary artery emboli among the autopsy cases with suspected acute myocardial infarction at the National Cardiovascular Center from 1977 to 1990. Of the 28 patients with emboli, 10% of the total autopsy cases of myocardial infarction was confirmed in 18. Infarction was diagnosed clinically in only six of these patients and directly caused the death of 11 of the 18 patients. In contrast to previous reports, where a minority of coronary emboli were caused by instrumentation, 14/28 patients in our series had coronary embolism due to invasive procedures, including eight patients with atheromatous emboli. half of the myocardial infarcts caused by embolism were hemorrhagic. Thus, coronary emboli are not so rare as once thought, and they may increase further with the progress of invasive diagnostic and surgical interventions. The possibility of coronary embolism thus needs to be kept in mind by all clinicians in the cardiovascular fields.