Coronary heart disease in the South African Bantu ∗

Abstract

The results are reported of a clinicopathologic investigation into three problems of cardiac disease in the South African Bantu: (1) the incidence of coronary atherosclerosis in the Bantu; (2) the effect of any such coronary atherosclerosis on the myocardium of the Bantu; (3) the problem of the large number of Bantu patients with cardiac disease reported as suffering from clinically unidentified heart disease, i.e., the so-called “cryptogenic” group of cardiac patients. The material consisted of 206 consecutive cardiac patients admitted to the Edendale Hospital medical wards over a six-month period, and of 513 necropsies specially investigated of a total of 1,048 autopsies performed at Edendale Hospital from June 1957 to June 1958. The postmortem material showed that coronary atherosclerosis does occur in the Bantu and is sometimes found in severe degree. The clinical findings were in agreement, e.g., the presence of myocardial ischemia in the cardiac patients was shown by the finding that angina pectoris was a not uncommon presenting symptom. In the postmortem and clinical series the incidence of proved frank myocardial infarction in the Bantu was about 1.4 per cent, an incidence higher than that reported by other workers but much lower than that in European patients. Histopathological examination of the autopsied hearts showed patchy fibrosis was a common finding in the myocardium of the Bantu dying of heart discase. There was a close relationship between the incidence and severity of patchy fibrosis and coronary atherosclerosis. The hearts of Bantu patients with cardiac disease suffering from occlusive disease of the coronary arteries and/or the ostia do not commonly present with gross frank myocardial infarction but rather with minute infarcts. A suggested explanation is advanced to account for this difference between Bantu and European patients suffering from coronary heart disease. It is suggested that the so-called “cryptogenic” group of Bantu cardiac patients consists largely of undiagnosed examples of well recognized causes of heart disease, notably coronary heart disease, decompensated hypertension and pericardial disease.