Sex-Related Differences in Patients Undergoing Thoracic Aortic Surgery: Evidence from the Canadian Thoracic Aortic Collaborative

Background: Contemporary outcomes after surgical management of thoracic aortic disease have improved; however, the impact of sex-related differences is poorly understood. Methods: A total of 1653 patients (498 [30.1%] female) underwent thoracic aortic surgery with hypothermic circulatory arrest between 2002 and 2017 in 10 institutions of the Canadian Thoracic Aortic Collaborative. Outcomes of interest were in-hospital death, stroke, and a modified Society of Thoracic Surgeons-defined composite for mortality or major morbidity (stroke, renal failure, deep sternal wound infection, reoperation, prolonged ventilation). Multivariable logistic regression was used to determine independent predictors of these outcomes. Results: Women were older (mean±SD, 66±13 years versus 61±13 years; P<0.001), with more hypertension and renal failure, but had less coronary disease, less previous cardiac surgery, and higher ejection fraction than men. Rates of aortic dissection were similar between women and men. Rates of hemiarch, and total arch repair were similar between the sexes; however, women underwent less aortic root reconstruction including aortic root replacement, Ross, or valve-sparing root operations (29% versus 45%; P<0.001). Men experienced longer cross-clamp and cardiopulmonary bypass times, but similar durations of circulatory arrest, methods of cerebral perfusion, and nadir temperatures. Women experienced a higher rate of mortality (11% versus 7.4%; P=0.02), stroke (8.8% versus 5.5%; P=0.01), and Society of Thoracic Surgeons-defined composite end point for mortality or major morbidity (31% versus 27%; P=0.04). On multivariable analyses, female sex was an independent predictor of mortality (odds ratio, 1.81; P<0.001), stroke (odds ratio, 1.90; P<0.001), and Society of Thoracic Surgeons-defined composite end point for mortality or major morbidity (odds ratio, 1.40; P<0.001). Conclusions: Women experience worse outcomes after thoracic aortic surgery with hypothermic circulatory arrest. Further investigation is required to better delineate which measures may reduce sex-related outcome differences after complex aortic surgery.