BACKGROUND The optimal timing of cardiac operations in patients with infective endocarditis continues to be debated. This observational study analyzed the profile and outcome of patients with active infective endocarditis undergoing operations. METHODS Between June 2000 and June 2006, 95 surgically treated patients with definite infective endocarditis by the modified Duke criteria were included. RESULTS Fifty-eight patients were operated on within the first 7 days after diagnosis of infective endocarditis and 37 at more than 7 days after diagnosis up to immediately after completion of antibiotic treatment. Staphylococci predominated and were significantly associated with embolism, abscess, and septic shock. The most frequent indication for operation was severe regurgitation with heart failure. The 6-month mortality was 15%. Early operation showed a trend towards increased mortality vs late operation. In univariable analysis, factors associated with 6-month mortality included staphylococci and septic shock. Multivariable analysis revealed that septic shock predicted 6-month mortality. Despite early operation in patients experiencing septic shock, 57% died. No patients without heart failure died after undergoing (early or late) procedures for severe regurgitation. CONCLUSIONS The prognosis in surgically treated patients was determined by the occurrence of septic shock. The outcome in patients who underwent late operations was favorable compared with the early group. This difference was probably not due to the timing of the surgical intervention but to the severity of infective endocarditis. In patients with severe regurgitation without heart failure, early operation may offer benefit in length of hospitalization and prevention of development of new heart failure.