Clinicopathologic findings in two young adults, who complained of ischemic cardiac arrest by ventricular fibrillation and of myocardial infarction complicated by cardiogenic shock respectively, are described. At coronary angiography, coronary arteries appeared normal. In both cases, detailed pathologic examination of the coronary arteries disclosed a focal eccentric atherosclerotic plaque in the proximal descending coronary artery, where selective coronary angiography had failed to reveal filling defects. These observations suggest a more critical attitude in evaluating angiographically normal coronary arteries in patients with myocardial infarction or aborted sudden death, and underline the possibility of arterial lumen stenosis underestimation, especially in the presence of eccentric plaque, with likely compensatory ectasia of the plaque-free wall segment.