Graft occlusions are the main problems that may arise during long-term follow-up period after coronary artery bypass surgery. Knowledge of pathologies developed in saphenous grafts and attempts to reduce their frequency are important for reduction of the incidence of saphenous graft vein occlusions. For today the patency rate for 10 years saphenous vein grafts are about 60%. Along with intraoperative technical factors, there are a lot of factors contributed to the development occlusion during long-term follow-up period. In this review we aimed to analyze the factors affecting saphenous vein pathologies and propose preventive measures.