Choice of conduits for coronary artery bypass grafting: craft or science?

Abstract

Long-term patency of a bypass graft is an important determinant in reducing morbidity and increasing survival after coronary bypass surgery. The purpose of this review is to analyse factors contributing to improved outcomes of commonly used conduits. Progress has been limited by the lack of uniform definitions of graft failure and development of appropriate statistical models. Evolving techniques for assessing patency at more frequent intervals has provided insight into the time and sites of early disease. The explosion of scientific knowledge of graft physiology has added to improving harvest, storage and early protection procedures thereby reducing early morbidity. Similarly, the understanding and management of risk factors have contributed to graft durability and possibly survival. Conduits have different characteristics and applications, which are patient dependent. Competitive flow remains a problem especially with arterial conduits; functional studies as opposed to anatomy of the target artery may improve understanding of the contribution of the collateral circulation. Selected patency data provide comparison between grafts. The role of the second internal thoracic artery graft is the subject of the Arterial Revascularisation Trial. Off-pump bypass procedures and patient characteristics affect conduit selection. Stroke is a major complication, which can be minimised by avoiding the aorta especially during off-pump surgery. There are few randomised controlled trials on the late outcomes comparing different bypass grafts and between bypass grafting and current percutaneous intervention methods. Accurate reporting of outcomes of graft patency will improve the scientific content and emphasise the importance of surgery in the management of coronary disease.

Endoscopic radial artery harvesting for coronary artery bypass grafting. A single center evolving experience

“…The arterial wall structure, comparable diameter, low-risk of harvesting site complications, and longterm preserved flow-mediated vasodilatation are perceived advantages of RA over the great saphenous vein (GSV) (ref. 5,6 ). Although, a number of observational studies have demonstrated the superiority of RA in terms of better patency and clinical outcome, randomized trials suggested only better angiographic results of RA in 1-year and 5-year follow-up with no difference in clinical outcome [5][6][7][8][9][10][11] .…”

“…5,6 ). Although, a number of observational studies have demonstrated the superiority of RA in terms of better patency and clinical outcome, randomized trials suggested only better angiographic results of RA in 1-year and 5-year follow-up with no difference in clinical outcome [5][6][7][8][9][10][11] . Moreover, dealing with less tight coronary lesions (<80%), particularly in the right coronary artery territory, and with the group of patients 70+, use of RA did not carry any benefit of importance over GSV (ref.…”

Vascular Reactivity and Flow Characteristics of Radial Artery and Long Saphenous Vein Coronary Bypass Grafts

“…2,3,15 Many factors determine graft patency, including patient characteristics, target vessel and conduit selection, 18 surgical technique, 18 postoperative medical therapy, and risk factor management. 19 The endothelium modulates vascular reactivity via a number of factors that include nitric oxide, endothelium-derived hyperpolarizing factor, and endothelin and also has antiproliferative and antithrombotic properties. 20 In our study, endothelial function was tested with acetylcholine.…”

Endothelial Denudation of Isolated Human Internal Mammary Artery Segments

“…Unlike saphenous vein graft, which has a median patency of 7 years, more than 90% of IMA grafts are patent at 15 years [21]. This in part is attributable to its endothelial function.…”