Chronic Treatment with Renin-Angiotensin System Inhibitors at Hospital Admission is Associated with Improved Reperfusion and Mortality Among STEMI Patients Undergoing Mechanical Reperfusion: Insight from the ISACS-STEMI COVID-19 Registry.

INTRODUCTION: Despite the large use of renin-angiotensin system inhibitors (RASI) in STSegment Elevation Myocardial Infarction (STEMI) patients, few data have been reported on the prognostic impact of chronic RASI at admission in patients suffering from STEMI, especially during the COVID-19 pandemic. Therefore, the current study investigated the prognostic impact of chronic RASI at admission in patients suffering from STEMI, including both SARS-CoV-2 positive and negative individuals, enrolled before and during the COVID-19 pandemic. METHODS: We included STEMI patients who received primary percutaneous coronary intervention (PPCI) and were enrolled in the ISACS-STEMI COVID-19 registry. In the present sub-analysis, patients were allocated according to chronic RASI therapy at admission. The primary study endpoint was the occurrence of in-hospital mortality. Secondary endpoints were postprocedural TIMI 3 flow and mortality at 1 month. RESULTS: The overall population was 15,693 patients, including 6,213 patients pretreated with RASI. Several differences in baseline characteristics were observed between the two groups. No difference was observed in the prevalence of SARS-CoV-2 infection. After correction for all baseline confounders, including procedural features, chronic pretreatment with RASI was independently associated with improved postprocedural TIMI 3 flow (OR [95% CI] = 1.14 [1.03-1.35], p = 0.042), lower in-hospital mortality (adjusted OR [95% CI] = 0.64 [0.54-0.75], p < 0.001), and lower 30-day mortality (adjusted OR [95% CI] = 0.62 [0.53-0.73], p < 0.001). CONCLUSION: This is the largest study investigating the prognostic impact and benefits of chronic RASI pre-treatment in STEMI patients undergoing PPCI, including those treated during the COVID19 pandemic. We found that chronic RASI treatment at hospital admission was associated with significant improvement in reperfusion and reduction in mortality, without any negative effect in SARS-CoV-2 positive patients. Results should be interpreted considering the retrospective, nonrandomized nature of the study.