AIMS: The impact of sex on adverse left ventricular remodeling (LVR) after ST-elevation myocardial infarction (STEMI) is unclear due to conflicting results. This study sought to establish sex-based differences in adverse LVR using Cardiovascular Magnetic Resonance (CMR) among STEMI patients and their impact on clinical outcomes. METHODS AND RESULTS: The study included patients with a first STEMI who underwent primary percutaneous coronary intervention (PCI). CMR was performed at 6 days (Interquartile range [IQR]: 4-9 days) and after 6 months (6.42 months
IQR: 5.98-7.47 months). Follow-up was 6.94 years (IQR: 4.48-9.32 years).The primary endpoint was the presence of adverse LVR (>
15% of LV end-diastolic volume and a decrease of >
3% in LV ejection fraction) at 6 months. The secondary endpoint was major adverse cardiac events (MACE), defined as a combined variable: cardiovascular death, heart failure admission, or ventricular arrhythmias.One thousand sixty-seven patients were included (17.5% women
mean age: 58.71±11.85 years). Women were older and had more cardiovascular risk factors (CVRF). There was no association between sex and adverse LVR (OR 0.80
95%CI 0.39-1.64, P=0.536). MACE occurred in 177 patients (16.7%) and was more frequent in women (22.6% vs. 15.4%, P=0.017). However, after adjusting for baseline differences and CVRF, the female sex was not associated with MACE (HR: 1.21 95% CI, 0.81-1.81, P=0.343). CONCLUSIONS: The higher rate of MACE after STEMI in women compared to men appears to be associated with a higher prevalence of CVRF and comorbidities rather than a more significant occurrence of adverse LVR.