Bioassay of EDRF from internal mammary arteries: implications for early and late bypass graft patency. Ann Thorac Surg. 1992;54:1078 84. 122. Luscher TF, Diederich D, Siebenmann R, et al. Difference between endothelium-dependent relaxation in arterial and in venous coronary bypass grafts. N Engl J Med. 1988;319:462 7. 123. Ivert T, Huttunen K, Landou C, et al. Angiographic studies of internal mammary artery grafts 11 years after coronary artery bypass grafting. J Thorac Cardiovasc Surg. 1988;96:1 12. 124. Geha AS, Baue AE. Early and lage results of coronary revasculariza- tion with saphenous vein and internal mammary artery grafts. Am J Surg. 1979;137:456 63. 125. Hashimoto H, Isshiki T, Ikari Y, et al. Effects of competitive blood flow on arterial graft patency and diameter. Medium-term postop- erative follow-up. J Thorac Cardiovasc Surg. 1996;111:399 407. 126. Seki T, Kitamura S, Kawachi K, et al. A quantitative study of postop- erative luminal narrowing of the internal thoracic artery graft in coronary artery bypass surgery. J Thorac Cardiovasc Surg. 1992;104: 1532 8. 127. Pagni S, Storey J, Ballen J, et al. ITA versus SVG: a comparison of instantaneous pressure and flow dynamics during competitive flow. Eur J Cardiothorac Surg. 1997;11:1086 92. 128. Shimizu T, Hirayama T, Suesada H, et al. Effect of flow competition on internal thoracic artery graft: postoperative velocimetric and angio- graphic study. J Thorac Cardiovasc Surg. 2000;120:459 65. 129. Pagni S, Storey J, Ballen J, et al. Factors affecting internal mammary artery graft survival: how is competitive flow from a patent native coronary vessel a risk factor? J Surg Res. 1997;71:172 8. 130. Nasu M, Akasaka T, Okazaki T, et al. Postoperative flow character- istics of left internal thoracic artery grafts. Ann Thorac Surg. 1995;59: 154 61. 131. Glineur D, D hoore W, El Khoury G, et al. 