Gender influence in isolated coronary artery bypass graft surgery: A propensity match score analysis of early outcomes

Introduction: The female gender has been shown as high-risk factor for mortality and morbidity. We sought to assess the influence of female gender on coronary artery bypass graft (CABG) surgery from our own experience. Methods: This is a retrospective analysis of prospectively collected database from a single centre. Patients were grouped according to gender and potential differences in pre-operative, intra-operative and post-operative factors were explored. Significant high-risk factors were then fitted in a multivariate model to account for differences in predicting gender influence on surgical outcomes. Results: Two thousand eight hundred and four consecutive patients underwent isolated first-time CABG between February 2000 and December 2008; 562 (20%) patients were females. Pre-operatively, females were more likely to have significant comorbidities (age, congestive cardiac failure, hypercholesterolemia, hypertension, ischemic heart disease, peripheral vascular disease, pre-op arrhythmias, small body surface area and poor ejection fraction (p < 0.001)) consistent with higher Euroscore (p > 0.0001) and more urgent surgery (p < 0.002). Intra-operatively, they showed less extent pattern of disease requiring less bypass and cross-clamp time (p < 0.001). Observed surgical mortality was significantly higher in females (3.6 vs. 2.1%, p < 0.042); however, after adjusting for propensity score and significant factors identified in multivariate models, females only independently predicted a higher wound infection, lower neurological complications, lower rate of re-sternotomy, longer hospital stay and post-surgery stay (p < 0.01). Conclusions: Despite higher risk profile and higher observed surgical mortality, early outcomes in females were similar to their matched males' counterpart in isolated CABG surgery. Females were associated with higher incidence of wound infections but lower rate of neurological complications. © The Japanese Association for Thoracic Surgery 2012.