OBJECTIVE To determine the clinical features and long term prognosis of infective endocarditis in patients who were not drug addicts.

DESIGN Prospective case series.

SETTING A university hospital that is both a referral and a primary care centre.

PATIENTS 138 consecutive cases of infective endocarditis diagnosed and treated from January 1987 to March 1997.

RESULTS Mean patient age was 44 (20) years old. 95 patients (69%) had native valve endocarditis and 43 (31%) had prosthetic valve endocarditis. Staphylococci were the causal microorganisms in 34% of cases and streptococci in 33%. Severe complications occurred in 83% of patients and 51% of patients underwent surgery during the active phase (22% was emergency surgery). Inpatient mortality was 21%. During a follow up of 56 (44) months, 10 patients (9%) needed late cardiac surgery and seven (5% of the whole series) died. Overall 10 year survival was 71%. There were no significant differences in survival depending on the type of treatment received during the hospital stay (medical or combined medical–surgical).

CONCLUSIONS A high early surgery rate is related to good long term results and does not increase in-hospital mortality. Medical treatment, however, also offers favourable long term results in cases of responsive infective endocarditis where poor prognostic factors are absent.