[Epidemiology and clinical aspects of infectious endocarditis]

There has been a change in the epidemiological, etiological and clinical pattern of infective endocarditis. This changing pattern has been substantiated by comparison of 156 cases of infective endocarditis seen over the period 1947-1957 (period I) and 227 cases treated during the period 1961-1974 (period II). Epidemiologically the pathomorphosis consists in a slight decline in "medical" cases, contrasted with a marked increase of--predominantly acute--cases after cardiac surgery. Etiologically the change is characterized mainly by a reduction of streptococci (61%/33%) and a much higher incidence of virulent organisms, especially staphylococci (3%/21%), as the infective agent. With regard to the clinical picture of infective endocarditis, the changing pattern is apparent in an increase in atypical and misleading features and an often oligosymptomatic presentation. In period II the classical signs were more often absent. The difference in the course of infective endocarditis consists in a higher hospital mortality during period II. In this period the main cause of death was refractory heart failure, often provoked by acute rupture of the aortic valve. The factors which may be responsible for this change and the clinical implications are discussed. The difficulties in early diagnosis and the role of misleading symptoms of this still "malignant" disease are outlined. Special interest is focused on the diagnostic problems involved in recognizing acute endocarditis, right-heart endocarditis and acute rupture of the aortic valve.