Sex Differences in Outcomes Following Acute Coronary Syndrome Treated With Coronary Artery Bypass Surgery

Background A person's sex is suggested to impact their outcome after acute coronary syndrome (ACS) and cardiac surgery, although evidence in controversial. This study examined sex differences in outcomes of ACS patients treated with coronary artery bypass grafting (CABG).Methods Patients aged >= 18 year with ACS and treated with first-time isolated CABG in Finland between 2004-2014 were retrospectively identified from a national registry (n=6,683, 24% women). Propensity score matching (1:1) was used to identify 1,607 women and 1,607 men with comparable baseline features (mean age 71 years and follow-up 7.1 years). In-hospital outcomes of all matched patients and long-term (10-year) outcomes of hospital survivors were studied.Results Women had higher in-hospital mortality (4.5 vs 2.6%; HR, 1.83; 95% CI, 1.18-2.86; p=0.008) but lower long-term all-cause mortality (28.3 vs 34.4%; HR, 0.70; 95% CI, 0.58-0.84; p<0.0001) and cardiovascular mortality (19.5 vs 23.7%; HR, 0.69; 95% CI, 0.55-0.86; p=0.001) as well as long-term major bleeding (11.6 vs 13.6%; HR, 0.69; 95% CI, 0.49-0.97; p=0.032). Re-sternotomy was also less common among women (3.7 vs 5.4%; OR 0.69; CI 0.49-0.96; p=0.029). There were no differences in length of stay (8.8 days in women vs 9.0 days in men) or in the occurrence of a composite major adverse cardiovascular event (MACE) in long-term follow-up (43.0% in women vs 46.5% in men; p=0.800).Conclusions Outcomes after CABG-treated ACS differed between sexes. Women had higher in-hospital mortality, while men had higher long-term mortality and occurrence of major bleeding. The long-term risk of combined MACE was comparable between sexes.