Beta-blocker Use in ST-segment Elevation Myocardial Infarction in the Reperfusion Era (GRACE)

Early administration of oral beta-blockers were associated with fewer cases of cardiogenic shock, ventricular arrhythmias, and new-onset heart failure, but compared with delayed beta-blocker administration, both oral and intravenous beta-blockers were associated with increased in-hospital mortality.

Abstract
Background
Current guidelines recommend early oral beta-blocker administration in the management of acute coronary syndromes for patients who are not at high risk of complications.

Methods
Data from patients enrolled between 2000 and 2007 in the Global Registry of Acute Coronary Events (GRACE) were used to evaluate hospital outcomes in 3 cohorts of patients admitted with ST-elevation myocardial infarction, based on beta-blocker use (early [first 24 hours] intravenous (IV) [± oral], only early oral, or delayed [after first 24 hours]).

Results
Among 13,110 patients with ST-elevation myocardial infarction, 21% received any early IV beta-blockers, 65% received only early oral beta-blockers, and 14% received delayed (>24 hours) beta-blockers. Higher systolic blood pressure, higher heart rate, and chronic beta-blocker use were independent predictors of early beta-blocker use. Early beta-blocker use was less likely in older patients, patients with moderate to severe left ventricular dysfunction, and in those presenting with inferior myocardial infarction or Killip class II or III heart failure. IV beta-blocker use and delayed beta-blocker use were associated with higher rates of cardiogenic shock, sustained ventricular fibrillation/ventricular tachycardia, and acute heart failure, compared with oral beta-blocker use. In-hospital mortality was increased with IV beta-blocker use (propensity score adjusted odds ratio, 1.41; 95% confidence interval, 1.03-1.92) but significantly reduced with delayed beta-blocker administration (propensity adjusted odds ratio, 0.44; 95% confidence interval, 0.26-0.74).

Conclusions
Early beta-blocker use is common in patients presenting with ST-elevation myocardial infarction, with oral administration being the most prevalent. Oral beta-blockers were associated with a decrease in the risk of cardiogenic shock, ventricular arrhythmias, and acute heart failure. However, the early receipt of any form of beta-blockers was associated with an increase in hospital mortality.

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–Kay Lee Park, MD, Robert J. Goldberg, PhD, Frederick A. Anderson, PhD, José López-Sendón, MD, Gilles Montalescot, MD, PhD, David Brieger, MBBS, PhD, Kim A. Eagle, MD, Allison Wyman, MS, Joel M. Gore, MD for the Global Registry of Acute Coronary Events Investigators

This article originally appeared in the June 2014 issue of The American Journal of Medicine.