CMR analysis of the cardioprotective effects of chronic statin therapy prior to first STEMI: a propensity score analysis

Abstract Background In addition to their lipid-lowering properties, statins possess cardioprotective effects. However, the impact of the latter on acute cardioprotection and adverse left ventricular (LV) remodelling following ST-elevation myocardial infarction (STEMI) have not been investigated through cardiac magnetic resonance (CMR) analysis to date. Purpose To investigate the cardioprotective effects of chronic oral statin treatment prior to first STEMI. Methods The study included 1236 patients with a first STEMI and a CMR performed during the index admission. Among them, 923 underwent a second CMR at 6 months follow-up. The effects of chronic oral statin treatment prior to STEMI on acute infarct size (IS) as a percentage of LV mass, LV ejection fraction (LVEF), microvascular obstruction (MVO), and changes in LV end-diastolic volume (EDVi) and end-systolic volume indexes (ESVi)] at 6 months were evaluated. A propensity score to receive treatment prior to STEMI with statins was calculated based on the inverse probability of treatment weighting (IPTW) from the following parameters: age on admission, sex, smoking status, type 2 diabetes, hypertension, family history of coronary artery disease, current co-treatments (ACEis/ARBs and/or beta-blockers), heart rate (HR), blood pressure (BP) and creatinine levels on admission, and pre-PCI TIMI flow in the culprit artery. Results were stratified according to a symptom-to-balloon time (S2Bt) ≤ or >3 hours. Results The study population's median age was 59 years (IQR 50–68), 16.3% were women; 18.9% were receiving treatment with statins prior to STEMI (table 1). Despite no effect on MVO occurrence (OR: 0.81 [0.60; 1.09], p=0.166), prior treatment with statins was associated with a reduction in IS (18.43% [16.67; 20.19] vs 21.50% [20.67; 22.34], p=0.002), particularly among subjects with ≤3 hours of S2Bt. Accordingly, prior treatment with statins conferred a benefit in mean baseline LVEF (50.23% [48.73; 51.73] vs 48.15% [47.43; 48.87], p=0.014). At 6 months, treatment with statins prior to STEMI blunted the changes in EDVi and ESVi, but only among patients with ≤3 hours of S2Bt (table 2). In addition, a reduction in the probability of adverse LV remodelling, defined as an increase in ESVi >10%, was observed in statin pre-treated patients (OR: 0.67 [0.45; 0.99], p=0.043). Conclusion Treatment with statins before STEMI is associated with improved indexes of cardioprotection as assessed by CMR, particularly among subject