The role of the female gender on mid-term outcome after coronary artery bypass grafting: a retrospective study

Abstract

Background: Data on female gender differences on clinical prognosis after coronary artery bypass grafting (CABG) are still controversial. We evaluated retrospectively the impact of women patients in comparison with men undergoing CABG on mid-term outcome.

Methods: Between December 2014 and March 2022, 1,044 consecutive patients (162 females, 15.5%, 882 males, 84.5%) underwent isolated CABG. The mean follow-up was 40±27 (median 38) months. Logistic and Cox model analysis regressions were used to assess the risk of female gender and other variables, Kaplan-Meier estimates to assess survival rates.

Results: Women did not have a significant higher operative mortality than men (3.09% vs. 1.93%; P=0.37). There was no difference in the use of left internal mammary artery (97.5% vs. 94.9%; P=0.85). Independent predictors of early mortality were emergency CABG (P<0.0001), percutaneous coronary intervention (PCI) within 30 days (P=0.0026), and higher EuroSCORE II (P=0.0155). At 7.5 years, actuarial survival was 87%±3.6% for female gender vs. 88%±1.9% in male gender (P=0.41), freedom from cardiac death 97%±1.8% vs. 96.6%±1.0% (P=0.6), freedom from major adverse cardiac events (MACE) 87%±6.2% vs. 89.7%±2.5% (P=0.96). Independent predictor of all-causes death and cardiac death was the advanced age (74 years in dead patients vs. 67 years in survivors) (P<0.0001). Female gender was not a predictor of either operative mortality (P=0.34) or worse mid-term outcome (P=0.41).

Conclusions: Women undergoing CABG with the same surgical techniques currently adopted for men, do not appear to be associated with worse early prognosis. Freedom from late all-causes mortality, cardiac death and adverse cardiac events are comparable and equally satisfactory, highlighting the positive protective effect of CABG over time also in women.

Keywords: Gender; coronary artery bypass grafting (CABG); women health.

Figure 1

Mid-term survival in female and male gender after CABG [mean follow-up, 40±27 (median 38) months]. The percentage estimates reported refer to 4 and 7.5 years of follow-up, respectively. CABG, coronary artery bypass grafting.

Figure 2

Freedom from late cardiac death in female and male gender after CABG. The percentage estimates reported refer to 4 and 7.5 years of follow-up, respectively. CABG, coronary artery bypass grafting.

Figure 3

Freedom from MACE. The percentage estimates reported refer to 4 and 7.5 years of follow-up, respectively. MACE, major adverse cardiac event.

Figure 4

Mid-term survival stratified by the severe degree of CRD [Log rank, Mantel-Cox test P value <0.0001; P value for gender interaction (female vs. male) =0.51]. The percentage estimates reported refer to 7.5 years of follow-up. CRD, chronic renal dysfunction.

Figure 5

Mid-term survival stratified by the EuroSCORE II risk profile (low, medium, high) (Log rank, Mantel-Cox test P value<0.0001; P value for gender interaction =0.87). The percentage estimates reported refer to 7.5 years of follow-up.