Background: Women have poorer outcomes in acute coronary syndrome (ACS) due to older age, comorbidities, atypical presentation and delay in admission. (1) The aim is to consider gender differences in outcomes in the Croatian Branch of the ISACS-CT registry.

Methods: From January 2012 to February 2017, 1808 patients were enrolled in the Croatian branch of the registry, 46% (n=844) presenting with acute ST segment elevation acute myocardial infarction (STEMI), 35% (n=637) with non-ST segment elevation myocardial infarction (NSTEMI) and 18% (n=327) with unstable angina. Sex ratio, male to female, was 2.2:1, the median age 65 (57-75) years. In-hospital mortality was defined as the primary outcome.

Results: There was no sex difference in type of ACS at admission. Women were significantly older, generally more burdened with comorbidities and arrived to the hospital with more delay from symptom onset (women vs. men: in the first 2 h - 19% vs. 24%, p=0.02; in the first 6 h - 49% vs. 58%, p<0.01). In patients with STEMI, logistic analysis showed female sex (OR = 2.9, CI 95% 1.1-8.1., p=0.04), diabetes (OR=2.7), creatinine levels (OR=1.01) and time from onset to admission (OR=0.65), as independent factors associated with in-hospital mortality (Figure 1). Considering time from symptom onset to admission, worse outcomes in women were visible only in the 2-6 hour window (women vs. men: 15.3% vs. 2.5%, p>0.01) (Figure 2). There was no gender difference in undergoing percutaneous coronary intervention (PCI), but successful revascularization was less often achieved in women (92% vs. 97%, p<0.01). Moreover, female sex (OR = 4.7, CI 95% 1.5-14.7, p=0.021), together with creatinine levels (OR=1.01) and GB IIB/IIIA administration (OR=2.7), proved independently associated with in-hospital mortality in the PCI group, whereas this effect was not seen in the non-invasive treatment group.

Conclusion: Gender differences in patients presenting with STEMI are visible in the Croatian branch of the ISACS-CT registry. In this setting, female sex bears risk of worse outcome associated with delay in admission and invasive treatment.