Influence of sex and age on long-term survival in systematic off-pump coronary artery bypass surgery

Background: Off-pump coronary artery bypass surgery (OPCAB) is commonty used as an alternative to conventional on-pump coronary artery revascularization. Historically, sex and age have been shown to adversely affect operative mortality risk as well as long-term survival in conventional surgery. Aims of the study: To evaluate the effect of gender and ageing on long-term mortality following OPCAB surgery. Methods: We have prospectively followed up 1000 consecutive and systematic OPCAB patients operated between September 1996 and April 2003. Average follow-up period was 64 28 months and was complete in 98% of the cohort. Results: There were 223 women (21%) and 777 men (79%). Women were older, 68 +/- 10 versus 63 +/- 10 years (p < 0.0001) and had higher prevalence of hypertension (p < 0.0001), peripheral vascular disease (PVD) (p = 0.03), recent myocardial infarction (p = 0.04) and a smaller body surface (p < 0.0001). History of congestive heart failure (CHF) (p = 0.001) and unstable angina (p = 0.003) was more frequent in men. Operative mortality was 2.8% in women and 1.4% in men (p = ns). Eight-year survival was 79 +/- 2.5% for men and 68 +/- 5% for women, (p = 0.02). Cox regression analysis model, revealed that age (HR: 2.81; 95% Cl: 1.89-4.18), CHF (HR: 2.09; 95% Cl: 1.33-3.31), PVD (HR: 1.72; 95% Cl: 1.10-2.5), incomplete revascularization (HR: 2.35; 1.37-4.02), multiple internal thoracic artery (MITA) graft/patient (ITA/pt) (HR: 0.61; 95% Cl: 0.44-0.84), left ventricular ejection fraction (LVEF) (HR: 0.19; 95% Cl: 0.05-0.71) and cerebral. vascular disease (HR: 1.50; 95% Cl: 1.00-2.24) but not female sex (p = 0.89) were significant predictors of long-term mortality. Above 65 years of age men and women had a comparable overall survival (p = 0.7) whereas fewer than 65 women had a lower survival than men (p = 0.001). Cox regression revealed that LVEF (HR: 0.06; 95% Cl: 0.006-0.59), Lesser use of MITA graft (HR: 0.45; 95% Cl: 0.35-0.79), were significant causes of long-term mortality in the younger cohort. Female gender did not reach statistical significance (p = 0.12). Conclusion: In this series of systematic OPCAB surgery, the lower survival rate observed in younger women was mostly related to a higher prevalence of preoperative comorbidity and a lesser use of MITA grafts than gender itself. (C) 2008 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V.. All rights reserved.