Choice of grafts — criteria for selection of coronary bypass conduit
The saphenous vein graft is the most commonly used bypass graft in coronary revascularization. Its main advantages are the relative ease of harvesting it, the usually large size of the vein and toughness of its wall, which make it easy to handle during construction of anastomoses, and the relative abundance of vein length which allows it to reach any site over the epicardium. However, saphenous vein grafts continue to have a somewhat unpredictable occlusion rate of about 10% at 2 weeks and 15% to 20% at 1 year postoperatively, despite refinements in the methods of preparation and handling of vein grafts. This has led us and others to investigate experimentally as well as clinically the use of internal mammary artery grafts for coronary bypass and to evaluate the results obtained with both types of grafts. This presentation will emphasize our own criteria for selection of one graft or another, the limitations of each and the results to be anticipated, based on a personal experience with coronary revascularization in 552 patients for surgical treatment of anginal syndromes and another 88 cases of revascularization in combination with other procedures (mainly valve replacement and/or myocardial resection) from January 1971 to June 1977.
The advantages of internal mammary artery grafts are (1) a single artery-to-artery anastomosis between vessels of comparable size with a natural origin of the graft from a parent major systemic artery; (2) the similarity in size of internal mammary artery graft and the recipient coronary artery tends to decrease the turbulent . . .