Sex Differences in Coronary Artery Bypass Grafting Techniques: A Society of Thoracic Surgeons Database Analysis

Background: Female patients with coronary artery disease have inferior outcomes compared with male patients, including higher mortality after coronary artery bypass graft surgery (CABG). We aimed to evaluate the association of female sex with the use of guideline-concordant CABG revascularization techniques.

Methods: The Society of Thoracic Surgeons Adult Cardiac Surgery Database was queried for adult patients who underwent first-time isolated CABG in the United States from 2011 to 2019. The association between female sex and the odds of (1) receiving a left internal mammary artery graft for revascularization of the left anterior descending artery, (2) undergoing complete revascularization, and (3) undergoing multiarterial grafting was assessed, adjusting for procedural anatomy.

Results: Among 1,212,487 patients meeting inclusion criteria, 75% were male (n = 911,178) and 25% were female (n = 301,309). Female sex was associated with lower unadjusted rates of revascularization with an internal mammary artery graft (93.9% vs 95.9%, P < .001), bilateral internal mammary artery graft (2.9% vs 5.6%, P < .001), or radial artery graft (3.2% vs 5.6%, P < .001). After adjustment, female patients had lower odds than males of receiving a left internal mammary artery graft to the left anterior descending artery (adjusted odds ratio 0.79; 95% confidence interval, 0.75 to 0.83; P < .001), undergoing complete revascularization (adjusted odds ratio 0.86; 95% confidence interval, 0.83 to 0.90; P < .001), and undergoing multiarterial grafting (adjusted odds ratio 0.78; 95% confidence interval, 0.75 to 0.81; P < .001).

Conclusions: Female sex was associated with 14% to 22% lower odds of undergoing guideline-concordant revascularization including left internal mammary artery to left anterior descending artery grafting, multiarterial grafting, and complete revascularization. Further investigation is necessary to determine why revascularization approaches differ by sex and to what degree sex disparities in coronary artery disease outcomes are due to surgical approach.