Objectives: Beta-blockade is currently recommended in the early management of patients with acute coronary syndromes (ACS). This was a systematic review of the medical literature to determine if early beta-blockade improves the outcome of patients with ACS.
Methods:The authors searched the PubMed and EMBASE databases for randomized controlled trials from 1965 through May 2009 using a search strategy derived from the following PICO formulation of our clinical question: Patients included adults (18+ years) with an acute or suspected myocardial infarction (MI) within 24 hours of onset of chest pain. Intervention included intravenous or oral beta-blockers administered within 8 hours of presentation. The comparator included standard medical therapy with or without placebo versus early beta-blocker administration. The outcome was the risk of in-hospital death in the intervention groups versus the comparator groups. The methodologic quality of the studies was assessed. Qualitative methods were used to summarize the study results. In-hospital mortality rates were compared using a forest plot of relative risk (RR; 95% confidence interval [CI]) between beta-blockers and controls. Statistical analysis was done with Review Manager V5.0.Results: Eighteen articles (total N = 72,249) met the inclusion ⁄ exclusion criteria. For in-hospital mortality, RR = 0.95 (95% CI, 0.90-1.01). In the largest of these studies (n = 45,852), a significantly higher rate (p < 0.0001) of cardiogenic shock was observed in the beta-blocker (5.0%) versus control group (3.9%).Conclusions: This systematic review failed to demonstrate a convincing in-hospital mortality benefit for using beta-blockers early in the course of patients with an acute or suspected MI.
ACADEMIC EMERGENCY MEDICINE 2010; 17:1-10 ª 2010 by the Society for Academic Emergency MedicineKeywords: adrenergic beta-antagonists, coronary artery disease, chest pain, myocardial infarction, angina
CLINICAL SCENARIOA 48-year-old man presents to the emergency department (ED) with new onset chest pain of 45 minutes' duration that occurred for the first time today. The pain was centrally located in the chest when it began and did not radiate. It dissipated after 10 minutes of rest and is no longer present at the time of evaluation. The pain was associated with some shortness of breath, but no nausea, vomiting, diaphoresis, or palpitations. The patient has hypertension and non-insulin-dependent diabetes and has smoked 1 to 1.5 packs of cigarettes per day for 20 years. His father died of a heart attack at age 45. The physical exam and vital signs are all within normal limits. The heart rate is 95 beats ⁄ min, blood pressure is 170 ⁄ 94 mm Hg, and finger stick blood sugar is 230 mg ⁄ dL. An electrocardiogram demonstrated deep and symmetrical T-wave inversions in the precordial leads V4-V6. The initial troponin is normal. The patient receives aspirin, and you decide to admit him to the telemetry unit for possible acute coronary syndrome (ACS). The patient's family physician requests that yo...