Of 26 patients who underwent both coronary artery bypass grafting and abdominal surgery at our institution between 1977 and 1992, nine had severe coronary artery disease associated with UICC stage I gastric cancer. They were treated by coronary artery bypass grafting followed by a curative operation for gastric cancer; the initial four patients underwent two-staged surgery (group A), and the most recent five patients underwent simultaneous surgery (group B). The cardiac surgery was performed first in all patients, and in group A the interval between the two procedures was 2 to 7 weeks. There were no significant differences between the two groups in terms of preoperative characteristics: sex, age, preoperative complications, NYHA class, prior myocardial infarction, ejection fraction, cardiac index, number of vessels diseased, or number of grafts. There were no significant differences between the two groups in terms of blood loss during the gastric operation (A: 649 +/- 194 ml; B: 842 +/- 326 ml) or the operating time (A: 371 +/- 106 minutes; B: 343 +/- 46 minutes). Two group A patients had postoperative complications (one had arrhythmia, and one died of sepsis caused by sutural insufficiency). On the other hand, four group B patients had complications (three cases of transient hyperbilirubinemia and one case of postoperative bleeding; none died). The postoperative hospital stay after gastrectomy was not prolonged in group B compared with group A (A: 41.7 +/- 22.7 days; B: 46.0 +/- 25.0 days). In conclusion, simultaneous procedure of coronary artery bypass grafting and gastric surgery can be performed safely, although careful management is indispensable.