Multi Versus Single Arterial Coronary Bypass Graft Surgery Across the Ejection Fraction Spectrum

Abstract

Left internal thoracic artery (LITA) and radial artery (RA) multi-arterial CABG (MABG) is generally associated with improved long-term survival compared with traditional LITA and saphenous vein single arterial CABG (SABG). We examined the hypothesis that this multi-arterial survival advantage persists irrespective of left ventricular ejection fraction (LVEF). We retrospectively analyzed the primary, non-salvage multi-graft CABG experience (n= 11,261; 64.4 ± 10.4 years, 70.4% men) from 2 institutions (1995 to 2011). Risk-adjusted 15-year survival was pairwise compared for the MABG versus SABG grafting approaches within 3 LVEF subcohorts (>0.50, n= 4,833 [44% MABG]; 0.36 to 0.50, n= 4,465 [39% MABG]; and ≤ 0.35, n= 1,963 [35% MABG]) using propensity-matched and covariate adjusted Cox regression (all patients) comparisons. Propensity matching yielded 1,317 (LVEF > 0.50), 1,179 (LVEF, 0.36 to 0.50), and 470 (LVEF ≤ 0.35) well-matched grafting method pairs. Acute perioperative mortality was equivalent between MABG and SABG within each LVEF group, but increased with decreasing LVEF. MABG was uniformly associated with better 15-year survival compared with SABG for all LVEF categories. The associated matched-adjusted hazard ratios (95% confidence intervals) were consistent across EF groups at 0.79 (0.68 to 0.93), 0.80 (0.69 to 0.93), and 0.82 (0.66 to 1.0), respectively. Covariate adjusted HR in all patients concurred with matched results. MABG results in significantly enhanced long-term survival compared with LITA/SVG SABG regardless of the degree of LV dysfunction. These results favor MABG as the therapy of choice in patients with LV dysfunction.