Of 88 consecutive patients aged 20 to 77 years with severe symptomatic aortic valve disease requiring surgery, 51 patients had angina pectoris; of these 51, 41 had predominant aortic stenosis and 10 had severe aortic regurgitation. All patients with angina pectoris underwent coronary angiography; significant coronary arterial disease was encounted in 24 per cent of those with aortic stenosis and 20 per cent of those with aortic regurgitation. By contrast, of 37 patients without angina pectoris 19 underwent coronary arteriography; none showed significant coronary artery disease (P smaller than 0.05). Among patients with angina pectoris, 17 per cent of those with aortic stenosis experienced prolonged, rest or nocturnal pain, compared to 70 per cent of those with aortic regurgitation (P smaller than 0.005). At the time of onset of angina pectoris, there were features of heart failure in 34 per cent of those with aortic stenosis, and in 90 per cent of those with aortic regurgitation (P smaller than 0.005). Nitroglycerin promptly relieved angina pectoris in 56 percent of patients with aortic stenosis and in 50 per cent of those with aortic regurgitation (P smaller than 0.05). Neither the pattern of angina pectoris nor the response to nitroglycerin was dependent upon the coexistence of significant coronary artery disease. In patients with aortic stenosis, there was not significant difference between those with angina pectoris, and those without angina with regard to left ventricular end-diastolic volume, end-diastolic pressure, ejection fraction, peak systolic pressure, wall thickness, cardiac index, or the product of these factors. In patients with aortic regurgitation, cardiac index was significantly lower (P smaller than 0.05), left ventricular end-diastolic volume tended to be larger, and ejection fraction tended to be lower in patients with angina pectoris as opposed to those without angina pectoris.