Background: It remains unclear if early use of intravenous (IV) beta-blockers (iBB) improves clinical outcomes patients with ST-segment elevation myocardial infarction (MI; STEMI), especially among those who received reperfusion therapy.
Objective: To evaluate effect of early iBB use on clinical outcomes among patients with STEMI.
Methods: A systematic review of randomized control trials in MEDLINE, EMBASE, CINAHL, and Cochrane databases comparing early use (administered within 12 hours of presentation) of iBB with standard medical therapy/placebo among patients who presented with STEMI. The effect of iBB was assessed by stratifying studies into pre-reperfusion and reperfusion trials and pooled treatment effects were estimated using relative risk with Mantel-Haenszel risk ratio, using a random-effects model
Results: Twenty-one studies (N=74,801) were selected for final analysis. Clinical outcomes at 30 days and 1 year are summarized in table below.
Conclusion: In the current reperfusion era, early use of iBB in patients with STEMI was associated with reduction in the risk of recurrent MI and ventricular tachyarrhythmias without any significant reduction in all-cause or CV mortality or increase in the risk of cardiogenic shock.