Coronary Artery Bypass Grafting Using Side-to-Side Anastomosis with Distal End Clipping of the Saphenous Vein Graft

Abstract

Although the Saphenous Vein Graft (SVG) is commonly grafted to the coronary artery with an end-to-side anastomotic technique, there is often a significant mismatch between the diameters of the SVG and the coronary artery, which may cause SVG failure. To overcome such a drawback of the standard end-to-side SVG anastomosis, we introduce a novel side-to-side anastomosis with distal end clipping of the SVG in coronary artery bypass grafting.The long-term outcome of Coronary Artery Bypass Grafting (CABG) depends predominantly on graft patency. Although an arterial graft is preferably used to improve long-term graft patency, a Saphenous Vein Graft (SVG) is also still widely used as a second bypass graft. The reported SVG patency ranging from 25% to >50% within 10 years was inferior to that of an arterial graft, despite considerable efforts to prevent SVG failure. Although the SVG is commonly grafted to the coronary artery with an end-to-side anastomotic technique, there is often a significant mismatch between the diameters of the SVG and the coronary artery, which may cause SVG failure. Moreover, the end-to-side anastomotic configuration has been reported to have an adverse effect on local hemodynamics, resulting in intimal hyperplasia in the long-term. The intimal hyperplasia, which is a major cause of late graft failure, has been shown to occur predominantly at the toe, heel, and bed of the host coronary artery around the distal anastomosis. TechniqueCABG is performed routinely with an off-pump technique in our unit. Initially, the skeletonized left internal mammary artery is grafted to the left anterior descending artery in a fundamental fashion. When the right internal mammary artery is used, it is grafted to the circumflex system through the transverse sinus. The gastroepiploic artery or the radial artery is rarely used. The SVG is used for the remaining coronary vessels such as the right coronary artery, the circumflex artery, and the diagonal branch. Sequential anastomoses with the SVG are performed in a diamond-shape or parallel fashion using a 7-0 polypropylene continuous suture, depending on coronary anatomy. The most distal side-to-side anastomosis is usually performed in a parallel fashion with a 7-0 polypropylene continuous suture (Figure 1). The distal end of the SVG is closed with surgical clips as close to the anastomosis as possible, paying attention not to cause any deformity at the anastomotic site (Figure 2). The SVG is then fixed to the epicardium at the heel of the anastomosis to avoid kinking. The proximal anastomosis is constructed on the ascending aorta with a 6-0 polypropylene continuous suture using a suture device. Figure 1: The distal end of the SVG is grafted to the coronary artery in a parallel end-to-end fashion with a 7-0 polypropylene continuous suture.