Staphylococcal endocarditis: clinical observations on 113 patients.

A 10-year analysis of 113 cases of staphylococcal endocarditis seen in two Washington, D.C., hospitals is presented. 96% of the cases occurred in parenteral drug addicts, but 4% complicated septicemia from known foci of infection. Coagulase positive staphylococcus was responsible for 97% of the infection, and the rest were caused by coagulase negative staphyloccus. Except in four patients with previously known cardiac murmurs, infection occurred on normal valves in these patients. Infection was isolated to the tricuspid valve in 71%, to the mitral valve in 6% and to the aortic valve in 3.5% of our cases; and more than one cardiac valve was affected in the remaining patients. All patients were treated with antibiotics based on bacterial sensitivity testing. The mortality from isolated tricuspid endocarditis was 5%, from isolated mitral endocarditis 33%, and from isolated aortic valve endocarditis 100%. The overall mortality was 18%. The better prognosis documented for acute tricuspid endocarditis is related to the much less severe haemodynamic consequences of acute tricuspid regurgitation, and the probably milder consequences of septic pulmonary embolism compared with coronary or cerebral embolism.