Our experience with St. Jude Medical (SJM) and CarboMedics (CM) prosthetic heart valves implanted in Korea during a 10-year period is presented. Between 1988 and 1997, 648 SJM and 601 CM valves were placed in 641 and 591 patients, respectively. Overall operative mortality was 3.4% and late mortality 8.2%; 10-year survival for all patients was 86.2%. At 10 years, 96.3% of patients were free from thromboembolism, and 97.6% were free from bleeding. There was no statistical difference between the two valves in terms of morbidity and mortality. Freedom from thromboembolism was seen in 96.7% of patients before institution of a Ôvalve clinicÕ permitting close follow up, and in 99.0% after clinic opening (p = 0.031). In contrast, freedom from bleeding fell from 99.3% to 96.1% respectively (p = 0.0004) during the same time frame, indicating a need for further investigations into the optimum therapeutic anticoagulation program.