Comparison of infective endocarditis in patients with and without previously recognized heart disease.

In a consecutive series of patients with infective endocarditis, we compared the charts of 123 nonaddicted patients without previously known heart disease with those of 174 patients with native valve disease. The 2 groups were similar in age, sex, clinical findings, and mortality rates, but infective endocarditis was more often located on the aortic valve, more often due to Streptococcus bovis and enterococci in patients without previously known heart disease.