The Cause of Death, Risk Factors and Long-Term Prognosis of Acute Myocardial Infarction

Abstract

Three hundred and eighty-six patients with acute myocardial infarction in the past 11 years between 1975 and 1985 were investigated retrospectively to clarify fatality, cause of death and long-term prognosis in relation to their risk factors and age. The average number of patients admitted in each year was 24.4 for the first 5 years and 44.0 cases per year in the last 5 years. The fatality decreased from 20.3% in the first 5 years to 15.7% in the last 5 years. A major cause of hospital death was cardiogenic shock and congestive heart failure. One hundred and thirty-six patients had coronary arteriography within 2 months after admission. They were divided into three groups; the young (⩽40 year old)-, middle (41—50 year old)-, and old (⩾51-year old)-aged groups. Among the young-aged group, serum cholesterol levels at admission were significantly higher in patients with multi-vessel lesions than those in patients without multi-vessel lesions, while there were many heavy smokers who did not show a significant lesion of the coronary artery. These observations suggest that hypercholesterolemia may act as an important risk factor for coronary arteriosclerosis in young patients, and also that a heavy smoking may promote an initiation of myocardial infarction in young patients without severe coronary artery stenosis. The cumulative 5 and 10 year survival rate for all groups was 84% and 61%, respectively. Fifty-seven patients had reinfarctions, and thirty patients died. The survivors were younger and had a good tolerance to treadmill exercise test at discharge. © 1987, The Japanese Circulation Society. All rights reserved.