Changing pattern of infective endocarditis.

There has been a significant trend toward an increase in the age of patients with endocarditis, and it seems likely that the age of these patients will continue to increase as the population ages. The proportion of patients with endocarditis who have rheumatic heart disease as an underlying lesion has decreased from about 40 percent in patients studied from 1950 to 1970 to about 25 percent in more recent series, and this trend will probably continue. Prosthetic valves and degenerative heart disease will undoubtedly become increasingly important underlying heart lesions in patients with endocarditis. Another large group of patients with infective endocarditis have no diagnosable underlying heart disease and comprise an increasing proportion of patients with endocarditis. Because of the aging of the population, more Streptococcus bovis and enterococcal endocarditis should be expected. With more prosthetic valves and with the aging of the population, more staphylococcal endocarditis should be anticipated. Economic forces will probably result in earlier discharge from the hospital, with either shorter courses of therapy or completion of therapy at home and perhaps more valve replacements.