Outcomes of Radial Artery Versus Saphenous Vein as A Second Conduit After Coronary Artery Bypass Grafting

Abstract

Despite the advantages of multiarterial grafting, saphenous vein (SV) configurations predominate in coronary artery bypass grafting (CABG). In addition, the benefits of radial artery (RA) utilization in multivessel CABG remain unclear. This study aims to compare the clinical outcomes of patients who received RA grafts during CABG with those of patients who received SV grafts. A retrospective, single-institution cohort study was performed in 8,774 adults who underwent isolated CABG surgery with multiple grafts between 2010 and 2022. To balance graft cohorts, propensity score matching (PSM) was performed using a 1:2 (RA/SV) match ratio. Long-term postoperative survival was compared in RA and SV graft groups. Similarly, major adverse cardiac and cerebrovascular event (MACCE) rates were compared in the cohorts, with MACCE comprising death, myocardial infarction (MI), coronary revascularization, and stroke. Kaplan-Meier estimation was performed for both mortality and MACCE. A total of 7,218 patients (82.3%) who underwent multivessel CABG were included in this analysis. Of these patients, 341 (4.7%) received RA grafts, and 6,877 (95.3%) received SV grafts secondary to left internal mammary artery use. PSM yielded a cohort of 335 patients with RA and 670 patients with SV. After matching, groups were well balanced across all baseline variables. No significant differences were observed in either immediate postoperative morbidities or long-term survival. However, Kaplan-Meier estimates of long-term postoperative freedom from MACCE were significantly greater in matched patients with SV (73.3%) than in those with RA (67.4%) (p = 0.044, cluster log-rank), with patients with SV also possessing significantly greater freedom from coronary revascularization and MI. In conclusion, RA and SV secondary conduits for CABG were associated with comparable immediate postoperative complications and long-term survival after PSM. SV grafting was associated with significantly decreased rates of postoperative MACCE, likely owing to lower rates of coronary revascularization and MI than in RA grafting.

Keywords: coronary artery bypass grafting; internal mammary artery; multiple arterial grafting; radial artery; saphenous vein.