['Coronary artery bypass grafting has been performed for a long period utilizing saphenous vein grafts, the fate of which might be crucial to prognosis following the operation. Metabolic syndrome, on the other hand, has become an increasingly important part of cardiovascular practice. We examined whether there was any negative effect of metabolic syndrome on saphenous vein graft patency in a relatively short term (< or =5 years).', 'Coronary angiograms of 314 consecutive patients (mean age 62.6+/-8.5 years), having at least one saphenous vein bypass graft within the last 5 years, were evaluated.', 'One hundred and twenty-one patients (group 1) had either an occluded saphenous vein graft or a saphenous vein graft with a significant lesion, and 193 patients (group 2) had patent saphenous vein grafts. Metabolic syndrome was present in 46.2% of all patients (n=145), in 57% of patients in group 1 and in 39.4% of patients in group 2 (P=0.002). Having metabolic syndrome increased the risk of saphenous vein graft occlusion or having a significant lesion on saphenous vein grafts by 2.04-folds. In multivariable logistic regression, smoking (P=0.015, odds ratio=1.88), metabolic syndrome (P=0.019, odds ratio=1.81) and diabetes mellitus (P=0.048, odds ratio=1.36) were found to be associated with poor venous graft fate in the relatively short-term period after bypass.'] Does metabolic syndrome negatively impact early patency of saphenous vein grafts?