Severity of coronary artery disease among blacks with acute myocardial infarction.

A growing body of evidence suggests that survival after acute myocardial infarction (AMI) is considerably worse among blacks than whites. The severity of coronary artery disease (CAD), as measured by the number of diseased vessels and the degree of left ventricular dysfunction, is the major determinant of survival after AMI. To determine whether or not the severity of CAD could explain the poor prognosis in a cohort of blacks followed at this institution, cardiac catheterization was performed in a consecutive series of 51 patients less than 70 years of age. All patients were studied within 2 weeks after AMI. The mean age of the patients was 56 +/- 8 (mean +/- standard deviation) and 71% were men. A greater than or equal to 50 narrowing in 0, 1, 2 or 3 coronary arteries was noted in 5, 24, 40 and 31%, respectively. Left main stenosis was present in 3 patients (6%) and the mean left ventricular ejection fraction was 55%. In a subgroup of 20 patients echocardiographic estimates of left ventricular mass/height yielded a mean of 196 g/m, and left ventricular hypertrophy on echocardiogram was present in 74%. These data indicate that among blacks with AMI in this series CAD was only modestly more severe than expected and suggest that other factors most likely explain the high mortality in blacks after hospital discharge.