[Bacterial endocarditis: clinical and bacteriological aspects and prognostic factors]

Abstract

The microbiological, clinical and therapeutic aspects of all (71) cases of bacterial endocarditis admitted to the Hôpital cantonal, Geneva, between August 1970 and October 1974 were reviewed: there was a definite trend towards higher prevalence of acute cases compared to subacute cases. The pathogenic role of S. epidermidis, mostly in cases of prosthetic valve endocarditis, could be demonstrated in several cases. When defined initially by microbiological criteria only, acute endocarditis were characterized by rapid evolution, destruction of the valvular structures (especially aortic valve), and by further evolution under adequate antibiotic therapy: thus, 10/25 patients with acute endocarditis died, whereas the mortality rate in the subacute cases was only 10/46. Many cases in our series showed one or more often frequent embolic phenomena: 70% of the cured cases and 80% of the patients with a fatal outcome. An unfavorable evolution could be correlated with neurologic involvement, cardiac rhythm or conduction disturbances, and/or heart failure; indeed, heart failure due to various mechanisms was the single most frequent cause of death and is presently the main therapeutic problem. Thus, acute infection leading to destruction of the aortic valve and to heart failure still carries a bad prognosis, even if emergency valve replacement is attempted. Finally, 22/30 patients who developed a bacterial endocarditis after oral or urological procedures knew about a heart murmur, but did not receive antibiotic prophylaxis. This clearly shows that emphasis should be put on the elaboration and diffusion of adequate prophylactic regimens.