Off-pump coronary artery bypass surgery in women.

Objective: Gender is a well-known risk factor for mortality and morbidity after coronary artery bypass grafting and various reasons have been proposed to explain the poorer results observed in women. The study objective was to determine whether female gender was still an operative risk factor with the adoption of off-pump coronary artery bypass surgery.

Methods: Of 2123 consecutive patients who underwent isolated CABG between November 2002 and December 2007, 1966 (92.6%) (481 women and 1485 men) were operated without cardiopulmonary bypass and form the study population. Women were older (69.0 vs. 64.7 years; p = 0.001) and had more severe angina (CCS class 3.1 vs. 2.7; p = 0.001), smaller body surface area (1.6 vs. 1.8 m2; p = 0.001), higher body mass index and greater incidence of diabetes (48.3% vs. 34.2%; p = 0.005) than men. There were no statistically significant differences in the incidence of three-vessel disease (69.5% vs. 71.9%) or left main disease (22.2% vs. 27.0%) but ejection fraction was higher in women (61.3% vs. 59.0%; p = 0.01). Risk factors for in-hospital mortality were identified by univariate analysis and logistic regression.

Results: The number of distal anastomoses was lower in women than in men (2.8 vs. 3.0; p = 0.001). In-hospital mortality was 2.0% in women and 0.8% in men (p = 0.01) and female gender was one of the eight risk factors for in-hospital mortality identified by univariate analysis. Using a logistic regression model, only age (OR: 1.7; 95% CI 1.01-1.14; p = 0.02) and logistic EuroSCORE (OR: 1.07; 95% CI 1.03-1.10; p < 0.001) were independently associated with in-hospital mortality. Logistic EuroSCORE was the only independent risk factor for major morbidity (OR: 1.07 95% CI 1.04-1.10; p < 0.001).

Conclusion: Women who undergo coronary artery bypass grafting have an unfavorable clinical profile compared to men, resulting in higher unadjusted in-hospital mortality. However, in an unselected patient population undergoing off-pump CABG, female gender was not found to be an independent risk factor for mortality or major morbidity.