The aim of this study was to evaluate the efficacy of adding the beta-blocker bucindolol to standard therapy shortly after a myocardial infarction in a high-risk population with reduced left ventricular function. METHODS: The study was planned to include 2000 patients with an enzyme confirmed myocardial infarction and severely reduced left ventricular function determined by echocardiography (corresponding to ejection fraction < or =0.35). The primary endpoint was all cause mortality and the secondary endpoints were time to first event of death, progression of heart failure or reinfarction-and the components. The study was closed early due to discontinuation of development of bucindolol by the manufacturer. Therefore, 170 patients were randomised to receive bucindolol and 173 to receive placebo. RESULTS: There were 27 deaths in the bucindolol group and 30 in the placebo group, hazard ratio of bucindolol 0.88 (95% confidence limits 0.5-1.5; P=0.6). There were 9/4 (bucindolol/placebo, P=0.16) heart failure events and 5/17 (P=0.01) reinfarctions in the bucindolol/placebo groups. CONCLUSION: Due to early closure it is unknown whether bucindolol changes mortality in high-risk post myocardial infarct patients when added to best medical therapy. The frequency of reinfarction was significantly reduced.