Conduits for coronary artery bypass surgery: the quest for second best

Abstract

Coronary artery bypass grafting is one of the most outstanding surgical achievements of the 20th century. Over its 50-year history patient outcomes have become excellent owing to technical refinements, myocardial protection, the use of antiplatelet and anticholesterol drugs, and the continued search for better conduits. The performance of conduits used for bypass remains the most important prognostic factor, with the left internal mammary artery being the conduit of choice due to its excellent patency rates. There is, however, uncertainty with regards which conduit is second best. The recent resurgence of the radial artery has led to an increase in its use as surgeons lean towards total arterial revascularization but there is emerging evidence that the performance of the long saphenous vein graft is improving. Furthermore, bilateral internal mammary artery grafting is preferred in some centres as an alternative approach to total arterial revascularization, with multiple reports of superior long-term event-free outcome with its use. This extensive review of current literature reveals an absence of clear consensus as to what mix of conduits provides the best long-term outcomes. The quest for second best continues. Arterial conduits appear to be superior when grafted to tight stenosis but veins remain popular with surgeons. More supportive evidence from the concluding Arterial Revascularization trial and the Radial Artery Patency and Clinical Outcomes trial should guide future practice.

The no-touch saphenous vein graft in elderly coronary bypass patients with multiple comorbidities is a promising conduit to substitute the left internal thoracic artery

“…Even if extensive arterial revascularization is performed, SVGs still account for the majority of conduits used in most centers. 34 This is due to numerous advantages of using the saphenous vein, including ease of access and manipulation, sufficient length for grafting, and short harvesting time. Clinical factors also may suggest that prolonged conduit longevity is not always the primary concern.…”

Development and In Vivo Evaluation of Small-Diameter Vascular Grafts Engineered by Outgrowth Endothelial Cells and Electrospun Chitosan/Poly(ɛ-Caprolactone) Nanofibrous Scaffolds

“…1 It is widely accepted that autologous vein is the ideal choice for bypass of the small diameter ( < 6 mm) diseased vessel, but that a suitable vein is not available in many patients owing to coexisting size mismatch or previous procedures. 2,3 Although a great deal of research has focused on the development of synthetic vascular grafts for decades, the current commercial grafts made from expanded polytetrafluoroethylene (ePTFE) or Dacron are far from satisfactory when utilized for the reconstruction of small-diameter arteries due to thrombosis, limited reendothelialization, and neointimal hyperplasia. 4,5 To overcome the shortcomings of synthetic vascular grafts, many studies focused on the creation of tissueengineered vascular grafts (TEVGs) prepared by recellularizing scaffolds with host vascular cells before implantation.…”

Review Up-to-Date Coronary Artery Bypass Graft Surgery

“…Annual graft occlusion occurs at a level of 2%, meaning that after 10 years, 60% of grafts are patent, although recent studies using a nontouch preparation technique refute these results. (23,24,25) …”