ATENOLOL USE AND CLINICAL OUTCOMES AFTER THROMBOLYSIS FOR ACUTE MYOCARDIAL-INFARCTION - THE GUSTO-I EXPERIENCE

Objectives. We assessed the use and effects of acute intravenous and l ater oral atenolol treatment in a prospectively planned post hoc analy sis of the GUSTO-I dataset. Background. Early intravenous beta blockad e is generally recommended after myocardial infarction, especially for patients with tachycardia and/or hypertension and those without heart failure. Methods. Besides one of four thrombolytic strategies, patien ts without hypotension, bradycardia or signs of heart failure mere to receive atenolol 5 mg intravenously as soon as possible, another 5 mg intravenously 10 min later and 50 to 100 mg orally daily during hospit alization. We compared the 30-day mortality of patients given no ateno lol (n = 10,073), any atenolol (n = 30,771), any intravenous atenolol (n = 18,200), only oral atenolol (n = 12,545) and both intravenous and oral drug (n = 16,406), after controlling for baseline differences an d for early deaths (before oral atenolol could be given). Results. Pat ients given any atenolol had a lower baseline risk than those not give n atenolol. Adjusted 30-day mortality was significantly lower in ateno lol-treated patients, but patients treated with intravenous and oral a tenolol treatment vs. oral treatment alone were more likely to die (od ds ratio, 1.3; 95% confidence interval, 1.0 to 1.5; p = 0.02). Subgrou ps had similar rates of stroke, intracranial hemorrhage and reinfarcti on, but intravenous atenolol use was associated,vith more heart failur e, shock, recurrent ischemia and pacemaker use than oral atenolol use. Conclusions. Although atenolol appears to improve outcomes after thro mbolysis for myocardial infarction, early intravenous atenolol seems o f limited value. The best approach for most patients may be to begin o ral atenolol once stable. (J Am Coil Cardiol 1998;32:634-40) (C) 1998 by the American College of Cardiology.