EComment. The best graft for the right coronary artery

Abstract

We read with great interest the paper by Mukherjee et al. [1] After reviewing five articles and due to the lack of studies dealing with long term follow-up, they concluded that the saphenous vein (SV) graft offers superior short and midterm outcomes compared to the right internal thoracic artery (RITA) for the revascularization of the right coronary artery (RCA). However, we believe that there are some issues that need to be addressed. Several papers [2, 3] have established the superiority of the use of bilateral internal thoracic arteries (BITA) to revascularize the left coronary system. Recently, the preliminary results of the randomized ART trial [4] confirmed the safety of using BITA grafts on a routine basis. In this trial, BITA grafts were anastomosed to the two most important left-sided coronary arteries with the supplemental vein or radial artery to the RCA. According to the literature [4, 5], BITA grafts for the left coronary circulation are considered by many as standardized practice. The remaining relevant question is which graft to use for the right coronary system. Although good overall patency for the radial artery (RA) and SV have been described, these are mostly observational studies and their results vary significantly. We are aware of only one randomized trial addressing this topic by comparing the performance of RA versus SV when used to graft the right coronary circulation. The RAPCO trial [5] assigned 621 patients to RA, SV, or free right ITA for the largest coronary target other than the left anterior descending coronary artery. A subgroup analysis [5] of patients over an 8-year period after primary coronary artery bypass graft surgery from RAPCO trial including patients who received a graft to the RCA, posterior descending artery, or left ventricular branch of the RCA using either a RA or SV showed that RA patency was comparable to that of the SV. Accordingly, the authors of RAPCO trial concluded that when considering grafting the RCA or its branches, the selection of best conduit may be made based on other factors. Further randomized controlled trials with longer follow-up periods are required to fully ascertain the best conduit for the RCA. Until then, the SV graft continues to be a routine practice for the revascularization of the RCA. Conflict of Interest: None declared