Comparative study between the gastroepiploic and the internal thoracic artery as a coronary bypass graft. Size, flow, patency, histology.

Ninety-two gastroepiploic artery (GEA) and 322 internal thoracic artery (ITA) grafts which underwent postoperative angiography (0.5-24 postoperative months, mean 2.0 months) were compared. The sites of GEA anastomosis were 5 left anterior descending, 3 diagonal, 16 circumflex and 68 right coronary arteries and for ITA grafts, 241 left anterior descending, 40 diagonal, 36 circumflex and 5 right coronary arteries. Patency rates were 96% (88/92) of GEA and 98% (314/322) of ITA, respectively. No focal stenosis in the graft trunk was found in both GEA and ITA except occasional spasm in GEA. Six (6%) GEAs were opacified via the superior mesenteric artery. Mean diameter of grafts just proximal to the anastomosis measured by angiogram was 2.3 mm in GEA and 1.9 mm in ITA (P less than 0.01). Free flow after intraluminal papaverine injection was 90.6 ml/min (50-300 ml/min) in 48 GEAs and 81.3 ml/min (50-150 ml/min) in 98 ITAs. Histology showed normal to mild intimal sclerotic changes in 58 of 63 (92%) GEAs and in 94 of 95 (99%) ITAs. From these results, we concluded that GEA is a suitable conduit and good long term patency similar to ITA grafting can be expected in coronary artery bypass grafting.