GRAFT FAILURE FOLLOWING CORONARY ARTERY BYPASS GRAFTING

Abstract

SUMMARY C oronary artery bypass surgery matured; either conventional or off-pump CABG surgery took many steps towards perfect revascularization specially in the last decade. Since the 1st successful CABG; argument never stopped to compare patency rates and duration of different conduit options used for CABG. Saphenous vein graft is a conduit that is more liable to graft: failure due to early intimal neoplasia; early thrombosis and late atherosclerosis compared to internal thoracic or radial artery; however, in many recent studies involved comparison between saphenous vein grafts and conduits other than internal mammary artery studies developed conclusion that is saphenous vein grafts are conduits which are safe for CABG with accepted results specially when combined to LIMA to LAD anastomosis in patients for CABG. Many new and novel strategies to increase saphenous vein patency rates developed which may be promising in the near future to increase saphenous vein patency. Internal mammary artery is a unique artery for grafting coronaries in-situ with perfect results and constitute. The most important step in the operation is to be anastomosed with left anterior descending artery with perfect patency rates up to 23 years of follow up after surgery. Radial artery is an important artery for arterial grafting of coronaries and since there is a Protocol for prevention of its spasm results balance very promising with perfect follow up angiography. Other arterial conduits can be used for CABG especially In re-operation with special attention to right-gastroepiploic artery which may be considered artery' of choice for grafting inferior surface of heart. Other arterial conduits are used in redo-patients with accepted patency rates. Intercostal artery is an ideal artery for in situ grafting which waits for clinical application. Several intrinsic and extrinsic factors may play a role in the mechanism of SVG failure. At the time of harvest, the quality of the saphenous veins may be poor, demonstrating a spectrum of pre-existing pathological conditions ranging from significantly thickened walls to post-phlebitic changes and varicosities. The most common graft-related causes of myocardial ischemia after CABG are graft occlusion due to acute graft thrombosis, graft kinking or overstretching, postoperative graft spasm and subtotal or hemodynamic relevant anastomotic stenosis The eSVS Mesh from Kips Bay Medical can play a role in preventing vein hyperplasia in coronary surgery and can ameliorate the long-term patency of vein grafts. However, further clinical trials are strongly recommended to confirm the long-term durability of meshed vein grafts implanted Antiplatelet agents and statin therapy are the only modalities with proven efficacy for the prevention of SVG stenosis. Comparison of BMS and DES for percutaneous revascularization of IMA Grafts, have reported conflicting results.

In conclusion, in patients with prior CABG presenting with ACS, PCI improves clinical outcomes compared to medical therapy alone. Redo CABG does not seem to further improve clinical outcomes.