Impact of off-pump techniques on sex differences in early and late outcomes after isolated coronary artery bypass grafts.

Background: Off-pump coronary artery bypass graft surgery (OPCAB) is associated with lower early mortality and benefits women disproportionately. The objective of this study was to assess the impact of off-pump techniques on sex differences in late outcomes.

Methods: We reviewed a clinical database of consecutive patients who underwent isolated coronary artery bypass graft surgery (CABG) at FuWai Hospital from 1999 to 2005. Logistic regression analysis and proportional hazards modeling were used to investigate whether sex or surgery type were associated with early mortality and late outcomes (mortality, major cardiac and cerebral event).

Results: Female sex was associated with higher rates of early death (adjusted odds ratio, 4.726; p < 0.0001), and OPCAB benefited women disproportionately for early mortality. Odds ratio of death for women versus men was 4.726 (p < 0.0001) in the conventional CABG on cardiopulmonary bypass group; odds ratio of death for women versus men was 1.344 (p = 0.5617) in the OPCAB group. Analysis of late outcomes indicated that OPCAB and cardiopulmonary bypass resulted in similar survival, regardless of sex. The women versus men hazard ratio of late mortality after CABG on cardiopulmonary bypass and OPCAB for women was 0.851 (p = 0.4984) and 0.650 (p = 0.2005), respectively. Women treated with OPCAB were less likely to be free from major cardiac and cerebral events than men treated with OPCAB. The women versus men hazard ratio of major cardiac and cerebral events after CABG on cardiopulmonary bypass and OPCAB for women was 1.079 (p = 0.4992) and 1.299 (p = 0.0387), respectively.

Conclusions: Compared with men, women are a high-risk group and benefit from off-pump operation in terms of early mortality after CABG. Conversely, during follow-up, women have high adjusted risks of major cardiac and cerebral events after OPCAB.