Abstract 11889: Impact of Beta-blockers on Long-term Survival in the Reperfusion Era

Abstract

Background: Although benefits of beta-blockers (BB) have been shown prior to the reperfusion era, it remains unclear whether BB improve survival in patients with ST-segment elevation myocardial infarction (STEMI) who receive reperfusion therapy (RT). We therefore aimed to evaluate the impact of BB on long-term survival of patients who received RT and who survived the index STEMI.

Methods: The AMI-QUEBEC Study was an observational study of all patients admitted for STEMI at 17 Quebechospitals (Canada) in 2003. We excluded patients with in-hospital deaths, patients without 5-year mortality data and patients who did not receive RT.We used Cox proportional-hazards models to evaluate the impact of BB on 5-year all-cause and cardiovascular (CV) mortalities, adjusted for age, female sex, type of STEMI, GRACE score, left ventricle ejection fraction (LVEF), diabetes, systolic blood pressure on admission, type of RT and other medications at discharge.

Results: There were 1,123 patients with STEMI and who received RT with available long-term survival data. The mean age was 60.4 years and 26% were females. Forty-five percent of patients received fibrinolytic therapy, 55% underwent primary percutaneous coronary intervention (PCI). At discharge, BB were prescribed for 87% of patients .The median follow-up was 57 months. There were 72 deaths (6.4%) of which 42 (3.7%) were of CV causes during follow-up. Although BB at discharge was not independently associated with 5-year all cause mortality (HR: 1.01, 95% confidence intervals (CI): 0.51-1.97, p=0.99), 5-year CV mortality was reduced by 53% (HR: 0.47, 95% CI: 0.24-0.92; p=0.03) .

Conclusion: Discharge prescription of BB was associated with long-term CV survival benefit in patients with STEMI who receive RT. Our results suggest that the CV survival benefit of BB, as shown prior to the reperfusion era, may be extrapolated to patients who receive RT.