Coronary artery bypass grafting represents one of the most frequent surgical procedure performed in the United States and Europe. The clinical benefit of myocardial revascularization is related to freedom of adverse cardiovascular events and to graft patency, above all of great saphenous vein, which is nowadays the main autologous vessel used for grafting coronaries different from anterior interventricular artery. Unfortunately, phenomena leading to early and, above all, late complications and to graft occlusion are not fully clarified and it so not possible to explain interindividual and temporary variability of progressive stenosis rate only on the basis of classical atherosclerosis risk factors. The aim of our study is to prospectively study the role of conventional risk factors (preoperative risk factors and clinical features) and of unconventional risk factors (genetic polymorphisms, inflammation and coagulation markers) with saphenous late patency and postoperative patients outcome, in particular with regard to adverse clinical events (myocardial infarction, successive stenting procedures, arrhythmias etc.)and to bypass patency.