Beta-blocker prescription and outcomes in uncomplicated acute myocardial infarction: Insight from the ePARIS registry

Abstract

Background: Systematic prescription of beta-blockers after myocardial infarction remains an open question in the era of revascularization, especially for patients with uncomplicated myocardial infarction.

Objective: To evaluate in a real-life registry the proportion of patients with uncomplicated myocardial infarction (preserved left ventricular ejection fraction and no cardiovascular event within the first 6 months), and to report their characteristics, outcomes and beta-blocker use.

Methods: We included 1887 consecutive patients with ST-segment elevation myocardial infarction from the prospective ePARIS registry. Patients were divided into three groups: the "uncomplicated myocardial infarction" group (n=1060), defined by a left ventricular ejection fraction ≥ 40% and a 6-month period free from cardiovascular events; the "complicated myocardial infarction" group (n=366), defined by a left ventricular ejection fraction ≥ 40% and a recurrent cardiovascular event in the first 6 months; and the "left ventricular dysfunction" group (n=461), defined by a left ventricular ejection fraction<40%.

Results: During a median follow-up of 2.7 years (interquartile range 1.0-4.9 years), the "uncomplicated myocardial infarction" group was at low mortality risk compared with the "complicated myocardial infarction" group (hazard ratio 0.38, 95% confidence interval 0.25-0.58; P<0.01) and the "left ventricular dysfunction" group (hazard ratio 0.22, 95% confidence interval 0.15-0.32; P<0.01). Beta-blockers were prescribed at discharge predominantly in the "uncomplicated myocardial infarction" group (93%) compared with 87% in the "complicated myocardial infarction" group and 81% in the "left ventricular dysfunction" group.

Conclusions: Beta-blockers are less prescribed in patients who may need them the most. The benefit of beta-blockers-largely prescribed in lower-risk patients-remains to be shown beyond the first 6 months for these patients with no left ventricular dysfunction and no recurrent events.

Keywords: Beta-blocker; Coronary intervention; Myocardial infarction.