Conventional coronary artery bypass grafting: why women take longer to recover

Recovery following successful coronary artery bypass grafting (CABG) has been dramatically improved with the use of fast-track methods. Although data exist that demonstrate a significant gender difference in survival following CABG, little is known about factors influencing gender-specific recovery. This report describes a series of consecutive patients undergoing isolated CABG to determine gender-associated factors that may impact outcomes and recovery.

Five hundred and seventeen consecutive patients underwent isolated CABG utilizing cardiopulmonary bypass and were retrospectively reviewed. The outcomes of 351 men in the study were compared to the group of 160 women. A rapid recovery protocol focused on reduced cardiopulmonary bypass time, aggressive preoperative intra-aortic balloon pump use, early extubation, perioperative administration of corticosteroids and thyroid hormone, aggressive diuresis and atrial fibrillation prevention was applied to all patients.

The 30-day mortality rate for the women was 4.2% (Parsonnet risk 16.3+/-9.0) compared with 3.4% (Parsonnet risk 9.9+/-7.5) for the men. There were no statistically significant differences in the 30-day mortality rates or postoperative complication rates between the women and men. The women, however, were found to be older (71+/- years versus 65+/- years, p<0.001), and to have a higher incidence of acute myocardial infarction (31% versus 20%, p<0.05), obesity (23% versus 10%, p <0.05), diabetes (31% versus 22%, p<0.05), hypertension (65% versus 48%, p<0.001), and symptomatic vascular disease (20% versus 12%, p<0.05). The women required fewer bypass grafts (2.9 versus 3.5 grafts, p<0.001), and consequently, had shorter cross and cardiopulmonary bypass times. Rapid recovery with discharge before the fifth postoperative day was achieved in 30% of the women, in comparison to 44% of the men (p<0.01). The postoperative hospital length of stay was longer for the women in comparison to the men (7.2+/-7.1 versus 5.8+/-5.2 days, p<0.05).

Women had similar operative mortality and postoperative complication rates to men under a rapid recovery protocol. However, women have a longer recovery interval compared to men, which may be a reflection of their higher preoperative risk profile.