A multicenter single blind prospective randomized superiority study is conducted. Our hypothesis is that there is difference in the incidence of "no-touch" saphenous vein graft patency using it as the conventional free graft (group C) and I graft (group I) for myocardial revascularization more than 28%. If there is truly difference between groups, then total 106 patients for both groups are required to be 90% sure that the upper limit of a one-sided 95% confidence interval would reveal a difference in favour of the "no-touch" saphenous vein I graft of 28%. The blinding process is applied to a patient, who is informed about received harvesting method of saphenous vein, but don't know the type of the graft cofiguration. The study was approved by Institutional Review Board. Depending on a type of the procedure, the patients are divided into two groups: conventional free graft (group C) 53 patients and I graft (group I) 53 patients. Randomization is conducted befor operation by using accidental sampling.
