The Impact of Multiarterial Grafting in Patients with Left Ventricular Dysfunction.

Background:  Coronary artery bypass grafting (CABG) is one of the revascularization modalities available in patients with left ventricular dysfunction (LVD). Multiple arterial grafting (MAG) is associated with improved long-term outcomes. Data on the benefits of MAG in patients with LVD are limited. We examined the effect of MAG on outcomes across the spectrum of left ventricle (LV) function.

Methods:  Retrospective cohort study of patients undergoing isolated CABG (January 1, 2009, to October 1, 2021). Patients were grouped according to revascularization strategy (single vs. MAG). The primary outcome was a composite of all-cause mortality, cerebrovascular accident, myocardial infarction, and repeat revascularization (major adverse cardiac and cerebrovascular events [MACCE]). The cumulative incidence of MACCE was plotted using Kaplan-Meier curves. Results were stratified according to LV function (<30%, 30-50%, >50%).

Results:  Our cohort included 4,763 patients; 1,976 (41.4%) underwent single arterial grafting (SAG), and 2,787 (58.6%) underwent MAG; 3,976 (83.4%) were male with a median age of 64 (interquartile range [IQR] 57-71) years. Distribution of LV function was 2,539 (53.3%) with an ejection fraction (EF) >50%, 1,828 (38.3%) with an EF of 30-50%, and 396 (8.3%) with an EF <30%. Median follow-up time was 64 (37-102) months. Cumulative incidence of MACCE at 72 months was 28.7% in the MAG and 30.3% in the SAG group. Stratified by LV function, the hazard ratio for MACCE at 160 months was 0.71 (95% CI 0.54-0.93), 0.78 (95% CI 0.68-0.9), and 0.95 (95% CI 0.83-1.09) for LV function <30%, 30-50%, >50%, respectively, with no significant interaction between MAG and LV function.

Conclusion:  MAG is associated with improved outcomes following CABG across the spectrum of LV function.