1Universitäres Herz- und Gefäßzentrum Hamburg Klinik für Herz- und Gefäßchirurgie Hamburg, Deutschland
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- 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 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. Furthermore a higher prevalence of common comorbidities involving chronic obstructive pulmonal disease, extracardiac artheropathy, kidney damage, s/p stroke and severely reduced left ventricular function was seen in group 2. Overall this resulted in a higher risk profile in group 2 as reflected by EuroSCORE II (1.2 [0.9-1.7] vs. 2.1 [1.5-3.38]; p<0.001). 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 differing baseline characteristics 30-day outcome parameters between groups were comparable with no differences in 30-day mortality, stroke or re-revascularization rates. Remaining differences were prolonged ventilation and catecholamine administration, a longer ICU stay and more administered red blood cell units in group 2 and a trend towards a higher frequency of DSWI in group 1 (18/646, 2.8% vs. 7/646, 1.2%; p=0.041).
Conclusions: After adjustment for baseline characteristics no differences in outcomes were found between groups. Therefore, application of BIMA should be also taken into consideration 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.