Vein graft failure
In medicine, vein graft failure (VGF) is a condition in which vein grafts, which are used as alternative conduits in bypass surgeries (e.g. CABG), get occluded. Veins, mainly the great saphenous vein (GSV) are the most frequently used conduits in bypass surgeries (CABG or PABG), due to their ease of use and availability. Some structural changes of intima thickening and vein wall remodeling are necessary for vein graft adaptation to the arterial environment. The reasons why some of the grafts progress to clinical stenosis is unknown. The patency rates of saphenous vein grafts after CABG at 1 year is approximately 80%. After 5 years the patency rate drops to 65% and at 10 years GSV patency rates are approximately 50%, with only half of the veins are atherosclerosis free. VGF may be identified in asymptomatic patients, but can also produce symptoms of ischemia, depending on the area of the supplied territory of the heart, and the function of native arteries and other grafts. VGF has been closely correlated with revascularization, myocardial infarction and death. Treatment of occluded GSVs can be performed by percutaneous coronary intervention or redo CABG and is considered to be challenging, and thus preventing their obstruction is