Management of infective endocarditis: seventeen years' experience.

Infective endocarditis remains a serious illness with a high mortality. In more than 75% of 417 patients, the infection was due to gram-positive microorganisms. The non-drug-addicted patients (33%) were elderly and debilitated with advanced illness that preceded the endocarditis. The drug-addicted patients (67%) were young and were infected with multiple kinds of microorganisms. The blood cultures grew strains of Staphylococcus aureus resistant to methicillin sodium and nafcillin sodium in a majority of patients. Gram-negative microorganisms and fungi were cultured almost exclusively from samples from the drug-addicted patients. The high mortality among the non-drug-addicted patients (28%) was related to their advanced age and debilitating illness. The high mortality among the drug-addicted patients (21%) was related to the complex bacteriology of their infections and the severe anatomical disruption of the valvular complexes of the heart. When cured of their disease after treatment with intravenously administered antibiotics or a valve procedure or both, their long-term survival was related to whether or not they abstained from their habit. If the patient abstained from the use of drugs, the chances of survival were good; if not, death invariably ensued. This experience strongly supports our contention that if a patient returns to the use of drugs and reinfects the valve after initial cure, a second valve operation is contraindicated.