From the epidemiological standpoint, certain impressions concerning myocardial infarction are widely held. The incidence of myocardial infarction (1) varies considerably in different parts of the world *; (2) has increased in recent years † and this increase is related to some changing factors in our civilization, such as the consumption of fats, dairy products, or tobacco ‡ (3) is much higher in men than in women § (4) reaches a peak at a later age in women than in men13; (5) is higher in white people than in Negroes ∥ (6) is higher in the upper socioeconomic groups than in the lower4; (7) is higher among persons with diabetes mellitus than among nondiabetics.# Even though these impressions are widely held, more data are needed in most instances to evaluate their status adequately. An extensive study of the epidemiological aspects of acute myocardial infarction based on autopsied patients and representing