Sex difference in outcomes after coronary artery bypass grafting: follow-up data of the Netherlands Heart...

Controversies exist regarding sex differences in outcomes after coronary artery bypass grafting (CABG). This study assessed sex differences in early and mid-term outcomes after CABG and factors associated with these differences. Outcomes were based on data from the Netherlands Heart Registration (NHR).

Data of patients undergoing CABG in the Netherlands between 2013 and 2019 were retrieved from the NHR database. Primary outcomes were early mortality, morbidity and mid-term survival. The population was divided into subgroups based on age (≥ 70 years and < 70 years). Regression analyses investigated the correlation between sex and both early and mid-term mortality.

This study included 41,705 male and 10,048 female patients. Median follow-up was 3.6 (1.8-4.8) years. Female patients were less likely to receive ≥ 2 arterial grafts (15.9% vs 23.2%, p < 0.001), had fewer anastomoses (3.2 ± 1.1 vs 3.5 ± 1.1, p < 0.001), higher 30-day mortality (1.9% vs 1.0%; p < 0.001) and a lower mid-term survival rate (91.3% vs 93.1%, p < 0.001). Perioperative complications, including myocardial infarction and stroke, were more common in female patients (all p < 0.001). Women aged < 70 years had a lower mid-term survival rate than men < 70 years (94.5% vs 96.0%, p < 0.001). Cox regression analysis showed that female sex was not significantly associated with mid-term mortality in the total cohort [hazard ratio (HR) 1.03; p = 0.45] but was associated with mid-term mortality in patients aged < 70 years (HR 1.19; p < 0.001).

Women undergoing CABG in our cohort presented with more complex risk profiles, received different surgical strategies and had worse early and mid-term outcomes compared to men. Female sex was associated with mid-term mortality only in patients < 70 years of age.