Angiocardiography and exercise testing at one month after a first myocardial infarction

The results of exercise testing (77 patients), left ventriculography and coronary arteriography (78 patients) are presented for men under the age of 60, one month after a first myocardial infarct. Cineangiocardiography revealed that patients with anterior infarction (n = 25) had both poorer left ventricular function and more totally occluded vessels than those with either inferior (n = 33) or subendocardial infarction (n = 20). In contrast, patients with inferior and subendocardial infarction had a greater proportion of myocardium supplied by sub-total lesions likely to be haemodynamically significant (75%-99% cross sectional area loss). Subendocardial infarction was also characterised by the best left ventricular function and the fewest number of total coronary occlusions. Stress testing showed that the combination of ischaemic ST segment changes and angina during exercise was 91% predictive of severe coronary disease (equivalent to triple vessel disease) while no angina in the presence of a negative test was 81% predictive of mild or moderate disease. Stenoses of 75%-99% cross sectional area loss were more common when angina occurred during exercise testing, and both angina and ischaemic ST segment changes occurred within ten minutes in all four patients with haemodynamically significant left main coronary artery lesions. Our data supports the usefulness of exercise testing after a first myocardial infarct and may provide valuable baseline information in the analysis of long term prognosis.