RESUMEN
Comparison of aortic and coronary atherosclerosis in the United States, Jamaica, Japan and India demonstrates that after the first two decades of life, there is a greater severity of intimal alteration in the United States than in the other population groups. The 3 foreign populations exhibited much less coronary atherosclerosis and a lower incidence of myocardial infarction. Their diets, too, were of lower caloric content and contained less than half the fat found in the United States diet. In Japan and Jamaica, atherosclerosis proved to be disproportionately more severe in the aorta than in the coronary arteries. Accordingly, appraisals of atherosclerosis limited to the aorta do no provide adequate indexes of geographical variations. A much lower proportion of complicated atheromatous lesions (ulcerated or calcified plaques) accounted for most of the differences observed. While there was a general parallelism between the severity of coronary atherosclerosis and the frequency of myocardial infarction, there were instances of cardiac infarction associated with relatively minor degrees of coronary intimal alteration. These situations indicate that virtually all grossly recognizable intimal lesions may be complicated by thrombosis (Summary)