Infective endocarditis: a survey of cases in the South-East region of Scotland, 1969-72.

The incidence and characteristics of infective endocarditis were studied in a defined community over a four-year period. Seventy-eight cases were found, giving an incidence of 16 cases permillion per year. The commonest presenting features were those of infection; 53% had cardiac failure and 37% evidence of emboli when first seen. Twenty-three cases occurred on rheumatic heart valves, 13 on valvular prostheses, and 19 in previously normal hearts. Streptococcus viridans was the commonest organism, but there was a relatively high incidence of staphylococcal infection. Only four cases were preceded by dental manipulation, and no source for the infection was found in 46 patients. The mortality rate was 46%, cardiac failure and embolic phenomena accounting for 65% of deaths. It is unlikely that earlier diagnosis or cardiac surgery would have reduced the mortality appreciably.