Gender's impact on outcome in coronary surgery with minimized extracorporeal circulation.

BACKGROUND

The role of female gender in cardiac surgery is still controversial. We examined the impact of gender on mortality after coronary artery bypass grafting (CABG) with minimized extracorporeal circulation (MECC).

METHODS

Between January 2004 and May 2009, 1,662 patients (439 females, 1,223 males) underwent CABG with MECC at the University Medical Center Regensburg. Perioperative data were retrospectively analyzed; primary end point was in-hospital mortality.

RESULTS

At operation, women were older, had a higher prevalence of diabetes and impaired renal function, and underwent more often non-elective surgery. Unadjusted mortality was significantly lower for men and than for women (2.3 vs. 5.7%; p = 0.001). Risk-adjusted mortality rates were derived by stepwise logistic regression. The final model reduced the gender-related mortality gap from 147 to 32%. Goodness of fit and discriminatory performance (AUC = 0.83) were good. Female gender, however, could not be identified as an independent risk factor for adverse outcome (OR 1.6; 95% CI 0.8-3.4). Risk-adjusted mortality was calculated as 4.9% in females and 2.6% in males. Low body surface area (<1.66 m(2)) was associated with excess mortality in females.

CONCLUSIONS

Gender-related disparity in outcome still remains present after surgery with minimized extracorporeal circulation. However, female gender per se is not an independent risk factor for in-hospital mortality, but close attention should be paid on modifiable risk factors.