Based on a good long-patency of the internal thoracic arteries (ITA) in coronary arterial bypass graft (CABG), the postoperative early patency of the inferior epigastric artery (IEA) was evaluated by means of the proximal anastomosed types as a composite graft. Among patients performed with CABG during October in 1998 to June, 2000, 39 cases with the IEA composite graft were studied for this clinical outcome (31 males and 8 females, the averaged age was 66.4 +/- 8.0 year old). The preoperative diagnosis were done as acute myocardial infarction (4), old myocardial infarction with angina pectoris (8), effort angina (12), and unstable angina (15). The coronary disease was left main trunk disease (8), 3 vessels (22), and 2 vessels (9). The operation was performed with cold blood-cardioplegia (20 degrees C, blood-GIK liquor used) on cardiopulmonary bypass with a single atrial and aortic cannulation. The averaged extracorporeal circulation time and the aortic clamping one were done for 169 and 131 min, respectively. The bypass number was double (n = 5), triple (n = 10), quadruple (n = 16), and quintuple (n = 8). Total bypass number was 150 (the averaged bypass number was 3.7 +/- 0.9), and total anastomosal number was 145. The postoperative early-patency of IEA was 94.9% (37/39). The proximal sites of IEA were anastomozed to ITA with I-shaped end-to-end (n = 15), to ITA with Y-shaped end-to-side (n = 5), and to SVG with Y-shaped end-to-side (n = 19). Compared with the postoperative early-patency of I-shaped anastomosis to ITA and that of Y-shaped one to ITA or SVG, there was no significance among these cases (100%, 15/15 versus 91.7%, 22/24, p = 0.6738), however, that of Y-shaped one to ITA was significantly better than that of Y-shaped one to SVG (60%, 3/5 versus 100%, 19/19, p = 0.0488). It should be available for spreading of the anastomotic objective vessels that the IEA as a composite graft was used with the proximal site anastomozed to ITA by I-shaped end-to-end and with to SVG by Y-shaped end-to-side, which clinical outcome would sufficiently benefit to the patients.