Effect of early metoprolol before PCI in ST‐segment elevation myocardial infarction on infarct size and left ventricular ejection fraction. A systematic review and meta‐analysis of clinical trials

AIM: This meta-analysis aims to look at the impact of early intravenous Metoprolol in ST-segment elevation myocardial infarction (STEMI) before percutaneous coronary intervention (PCI) on infarct size, as measured by cardio magnetic resonance (CMR) and left ventricular ejection fraction. METHODS: We searched the following databases: PubMed, Scopus, Cochrane library, and Web of Science. We included only randomized control trials that reported the use of early intravenous Metoprolol in STEMI before PCI on infarct size, as measured by CMR and left ventricular ejection fraction. RevMan software 5.4 was used for performing the analysis. RESULTS: Following a literature search, 340 publications were found. Finally, 18 studies were included for the systematic review, and 8 clinical trials were included in the meta-analysis after the full-text screening. At 6 months, the pooled effect revealed a statistically significant association between Metoprolol and increased left ventricular ejection fraction (LVEF) (%) compared to controls (mean difference [MD] = 3.57, [95% confidence interval [CI] = 2.22-4.92], p < .00001), as well as decreased infarcted myocardium(g) compared to controls (MD = -3.84, [95% [CI] = -5.75 to -1.93], p < .0001). At 1 week, the pooled effect revealed a statistically significant association between Metoprolol and increased LVEF (%) compared to controls (MD = 2.98, [95% CI = 1.26-4.69], p = .0007), as well as decreased infarcted myocardium(%) compared to controls (MD = -3.21, [95% CI = -5.24 to -1.18], p = .002). CONCLUSION: A significant decrease in myocardial infarction and increase in LVEF (%) was linked to receiving Metoprolol at 1 week and 6-month follow-up.