Radial artery graft patency relates to gender, diabetes mellitus and angiotensin inhibition

Abstract

The radial artery is resistant to atherosclerotic degeneration and therefore appears more attractive for coronary artery bypass grafting than the saphenous vein. However, the patency of radial artery grafts varies widely among studies. Therefore, before deciding whether to adopt this as the conduit of choice second to internal mammary artery grafts, we have prospectively monitored our first cohort of patients with radial-to-coronary bypasses. Design. Angiographic and clinical outcome parameters were registered for the 119 patients receiving radial artery grafts at our institution during April 4, 2001 to October 7, 2003. Results. Reangiography of 102 patients (86%) showed that after two to three years, 79% of the radial artery and 87% of the saphenous vein grafts remained patent. Radial artery harvesting was well tolerated. Patency of radial artery grafts was correlated to diabetes mellitus (detrimental), gender (women had higher occlusion rates), and use of angiotensin inhibiting medication (beneficial). Conclusions. The pre-study assumption that radial artery grafts would out-perform those of saphenous vein at mid-term is not borne out. The propensity of radial artery graft failure in diabetics and the higher patency associated with angiotensin inhibition might both relate to endothelial modulation of the muscular tone of the graft.