The aim of this study was to determine the indication for minimally invasive direct coronary artery surgery based on the operative and long-term results of conventional coronary artery bypass grafting with cardiopulmonary bypass. Operative results: The subjects included 505 patients who underwent isolated elective coronary artery bypass grafting with cardiopulmonary bypass from January 1995 through August 1999. The mean age at the time of surgery was 61.9 and the mean number of grafts per patient was 2.6. Long-term results: From January 1984 to December 1995, a total of 907 patients received coronary artery bypass grafting with cardiopulmonary bypass using the internal thoracic artery to the left anterior descending artery with or without saphenous vein grafts to other coronary arteries. The rates of complete and incomplete revascularization were 69.3% (n = 629) and 30.7% (n = 278), respectively. Mean follow-up was 5.95+/-3.0 years. The operative results revealed low output syndrome occurred in 14 patients (2.8%), perioperative myocardial infarction with the appearance of new Q-waves in 5 (1.0%), renal failure requiring transient dialysis in 16 (3.2%), stroke with persistent sequelae in 5 (1.0%), and mediastinitis in 5 (1.0%). Two patients (0.4%) died in the hospital. The long-term results for the 907 patients revealed the 10-year actuarial survival, 10-year cardiac death free, and 10-year cardiac event free rates were 85.7%, 94.1%, and 77.3%, respectively. The 10-year survival rates was 88.4% among patients receiving complete revascularization and 79.3% among those receiving incomplete revascularization (p = 0.0334). The 10-year cardiac death free rate among patients undergoing complete revascularization was 96.3% and 88.7% among those receiving incomplete revascularization (p = 0.0016). The 10-year cardiac event free rates were 82.3% and 67.9%) among patients undergoing complete and incomplete revascularization, respectively (p = 0.0118). In view of the favorable operative and long-term results of conventional coronary artery bypass grafting, especially complete revascularization, we conclude that minimally invasive direct coronary artery grafting is an appropriate treatment for multi-vessel disease in carefully selected patients at a high risk for stroke and major comorbidities due to old age.