Flowmetric Assessment of the Free Right Internal Thoracic Artery Anastomosed Proximally to a Saphenous Vein Graft to Revascularize the Left Coronary Artery System

Abstract

In coronary artery bypass grafting (CABG), arterial grafts provide superior results compared with saphenous vein grafts (SVGs). Among arterial grafts, using bilateral internal thoracic artery grafts is associated with good survival benefits and graft patency-. However, in-situ right internal thoracic artery grafting (RITA) is used for limited coronary arteries because of the insufficient length. In contrast, free RITA grafts can be used for sequential multiple grafting and grafting to the distal branches. Therefore, in multi-vessels bypass grafting, free RITA grafting can be more feasible than in-situ RITA. In addition, we avoid retrosternal in-situ RITA crossover routing due to concerns about the potential risks of damage to the RITA in re-sternotomy or deep sternal wound infection. For these reasons, the free RITA is used as the second graft alternative in our institute, except in older patients. When using free RITAs, there are several alternatives as a proximal anastomotic site, such as the aorta, a left internal thoracic artery graft (LITA), a radial artery graft, or a SVG-. Among these anastomotic sites, SVGs are technically the most simple, and we anastomose a free RITA to the hood of the SVG close to the suture line of its aortic anastomosis. In this technique, there is concern regarding a flow-steal phenomenon between the two grafts as in composite Y-grafting with the LITA . However, correlations in the graft flow between a free RITA and an SVG have not been clarified. We report the operative results following CABG using free RITAs in our institute and the results of a flow measurement study of proximally anastomosing a free RITA to the hood of a SVG at its aortic anastomosis.