Since 1958 up to the end of October 31, 1980, 2032 cases of cardiovascular lesions were operated, including 1225 open heart surgery and 354 valve replacement patients. There were 1271 Congenital anomaly cases and 761 acquired lesions including 149 vascular lesions. Among 1~271 congenital malformations 819 cases belong to acyanotic and 452 to cyanotic group. Over all mortality was 11.1 %, consisting of 12.4% for congenital and 8.9% for acquired lesions. Mortality for 1225 open heart surgery cases was 15% and 13.8% for various 354 valve replacement cases. In most of the open heart surgery cases Shiley oxygenator was utilized and Ionescu-Shiley bovine pericardial xenograft bioprosthesis**** valves were used mainly for valve replacement