Utilization of Vein Grafts in Coronary Artery Bypass Grafting: Reasons and Outcomes in a Bilateral Mammary Artery First Center

Objectives. Despite guideline recommendations for use of bilateral internal mammary artery (BIMA) in coronary artery bypass grafting (CABG), a large proportion of patients still receive saphenous vein grafts (SVG). We herein aimed to identify reasons for SVG use at a center with a BIMA utilization rate between 60 and 70% and compare outcomes of patients undergoing CABG with either BIMA or left internal mammary artery (LIMA) plus SVG. Methods. Between 2013 and 2022, 4145 consecutive patients underwent isolated CABG at our center. Of those, 2067 patients received BIMA (group 1) and 1206 patients received LIMA/SVG (group 2). A propensity score-matched analysis was performed to adjust for baseline differences. Results. Group 2 presented with higher age, more female patients, and more patients with acute coronary syndrome including NSTEMI/STEMI with more urgent/emergency CABG. In unadjusted analysis group 2 presented adverse 30-day outcomes compared to group 1 with a higher mortality (18/2067, 0.9% vs. 34/1206, 2.8%; $p<0.001$), higher rate of re-revascularization (52/2067, 2.5% vs. 50/1206, 4.1%; $p<0.001$), more stroke (20/2067; 1.0% vs. 33/1206, 2.7%; $p<0.001$), and more postoperative renal failure (17/2067, 0.8% vs. 27/1206, 2.2%; $p=0.001$). After adjustment for baseline characteristics, 30-day outcomes were comparable. Conclusions. After adjustment for baseline characteristics no differences in outcomes were found between groups suggesting a safe applicability of BIMA even in patients with acute coronary syndrome undergoing urgent/emergency CABG. Reasons for SVG use were higher age, female gender, and acute coronary syndrome with urgent/emergency CABG. Outcomes of both groups were excellent with low rates of primary endpoints.