Association between plasma asymmetrical dimethylarginine activity and saphenous vein graft disease in patients with coronary bypass

Abstract

Coronary vein graft disease is an important contributor to the morbidity after coronary artery bypass graft surgery. Graft occlusion is a serious complication, which limits the use of the saphenous vein as a coronary bypass conduit. Asymmetrical dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase and it reduces the bioavailability of nitric oxide and begets endothelial dysfunction. The goal of this study was to examine the association between plasma ADMA activity and saphenous vein graft disease. One hundred and three patients were enrolled in this study. Group 1 consisted of 42 patients (13 female, 29 male) who had diseased saphenous vein grafts and group 2 consisted of 61 patients (10 female, 51 male) with nondiseased saphenous vein grafts. ADMA activity was measured by the enzyme-linked immunosorbent assay kit. Mean ADMA activity in group 1 was significantly higher than in group 2 (2.0+/-0.6 vs. 1.1+/-0.5 micromol/l, P<0.001, respectively). Mean platelet volume was also significantly higher in group 1 than in group 2 (8.7+/-1.5 vs. 8.2+/-0.6 fl, P=0.03, respectively). In a multivariate linear regression analysis, ADMA activity (beta=2.902, P<0.001) and mean platelet volume (beta=0.595, P=0.03) were found to be independent predictors of saphenous vein graft disease. Our results showed that ADMA activity was higher in patients with saphenous vein graft disease. Increased ADMA activity might lead to the acceleration of saphenous vein graft disease. ADMA may be a precious marker for detecting late saphenous vein graft patency.