Acute heart failure: a mechanism underscoring sex differences in outcomes following acute coronary syndromes

Background It remains uncertain whether female sex is itself a strong risk factor for worse outcomes in acute coronary syndromes (ACS). Purpose We hypothesized that sex differences in vulnerability to heart failure after ACS may modify the association between sex and outcomes. Methods Data were drawn from the ISACS-Archives network of registries. The study population consisted of 87,812 patients with known time from symptom onset to hospital presentation. Participants were stratified by ACS subtypes: STEMI and NSTE-ACS Data on presenting heart failure symptoms were collected from medical record abstraction. Heart failure was categorized as Killip class >2. Time from symptom onset to hospital presentation was categorized as early (≤120 minutes) or late (>120 minutes). Primary outcome measure was 30-day mortality. Estimates were performed using a parametric balancing strategy by weighting and compared by test of interaction on the log scale. Results Among the study sample, 30922 (35.2%) patients were women. Patient outcomes varied according to subtype of ACS. The mortality rates at 30-days were significantly higher among women vs men in STEMI (RR:1.65; 95% CI: 1.56–1.73) compared with NSTE-ACS (RR:1.18; 95% CI: 1.09–1.28; P interaction Conclusions Women exhibit substantially more vulnerability to heart failure in STEMI than men: a greater percentage of women have heart failure, and women with heart failure have higher 30-day mortality than men with heart failure. This finding was not seen in NSTE-ACS. heart failure on initial assessment is a key feature to explain the sex gap in mortality after ACS. Funding Acknowledgement Type of funding sources: None.