Outcomes following coronary artery bypass grafting with multiple arterial grafting by pump status in men and women

Objective — Multiple arterial grafting (MAG) and off-pump surgery are two strategies proposed to improve outcomes with coronary artery bypass grafting (CABG). To determine the impact of off-pump surgery on outcomes after CABG with MAG in men and women.

Methods — This cohort study used population-based data to identify all Ontarians undergoing isolated CABG with MAG between October 2008 and September 2019. The primary outcome was all-cause mortality. Secondary outcomes included major adverse cardiac and cerebrovascular events (MACCE) (hospitalization for stroke, myocardial infarction hospitalization or heart failure, or repeat revascularization). Analysis used propensity-score overlap-weighted cause-specific Cox proportional hazard regression.

Results — 2,989 women (1,188 off-pump, 1,801 on-pump) and 16,209 men (6,065 off-pump, 10,144 on-pump) underwent MAG with a median follow-up of 5.0 (IQR: 2.7-8.0) years. Compared to the on-pump approach, all-cause mortality was not changed with off-pump status (hazard ratio [HR] in women: 1.25 [95% CI 0.83, 1.88]; in men: 1.08 [0.85, 1.37]). In women, MACCE risk was significantly higher off-pump (HR 1.45 [1.04-2.03]) with non-significant increased risks observed for all component outcomes.

Conclusion — In patients undergoing CABG with MAG, this population-based analysis found no association between pump status and survival in either men or women. However, it did suggest that off-pump MAG in women may be associated with an increased risk of MACCE.