Between April 9, 1986 and September 2, 1987, 134 patients underwent open heart surgery with hypothermic cardiopulmonary bypass and cold blood cardioplegia. There were 65 patients[48.5%] of acyanotic congenital cardiac anomalies, 19 patients[14.2%] of cyanotic congenital cardiac anomalies, and 50 patients[37.3%] of acquired heart diseases, which included 49 valvular diseases and 1 myxoma. In 84 congenital cardiac anomalies, 44 patients were male and 40 patients were female ranged in age from 2 years to 57 years. In 50 acquired heart diseases, 18 patients were male and 32 patients were female ranged in age from 10 years to 65 years. The common congenital defects operated were VSD in acyanotic cardiac patients, and Tetralogy of Fallot in cyanotic cardiac patients. Among 50 acquired heart diseases, 49 patient underwent operation for cardiac valvular lesions. 33 patients had mitral valve replacement and 7 patients had aortic valve replacement. 1 patient underwent aortic valvuloplasty and 8 patients had double valve replacement. The operative mortality rate was 3.1%[2 out of 65 patients] in acyanotic cardiac patients, 5.3%[1 out of 17 patients] in cyanotic cardiac patients, and 12.0%[6 out of 50 patients] in acquired cardiac patients, with overall mortality rate of 6.7%[9 out of 134 patients].