Efficacy of epanolol versus metoprolol in angina pectoris: report from a Swedish multicentre study of exercise tolerance

Abstract

The efficacy of epanolol vs. metoprolol in stable angina pectoris was compared in 114 patients recruited to a randomized double-blind cross-over study, consisting of a 4-week period on each drug. Epanolol (200 mg) or metoprolol (200 mg) was administered daily. Bicycle ergometry was performed at the end of each treatment period. The maximum workload was 134 +/- 18 W on epanolol and 133 +/- 37 W on metoprolol (NS). Values for resting heart rate (epanolol, 72 +/- 11 beats min-1; metoprolol, 64 +/- 12 beats min-1; P less than 0.001), systolic blood pressure (epanolol, 143 +/- 21 mmHg; metoprolol, 137 +/- 21 mmHg; P less than 0.05) and diastolic blood pressure (epanolol, 88 +/- 10 mmHg; metoprolol, 84 +/- 11 mmHg; P less than 0.01) were all higher on epanolol treatment. During exercise, the increase in heart rate and blood pressure was of similar magnitude during the two treatment periods, and these parameters did not differ significantly at the last identical workload. The rating of chest pain, fatigue and dyspnoea did not differ between the two drugs during submaximal or maximal exercise. In conclusion, 200 mg of epanolol and metoprolol have similar efficacy with regard to exercise tolerance. As expected from the partial agonist activity present in epanolol but not in metoprolol, the former drug resulted in a higher heart rate and blood pressure at rest. The observed increase in these parameters during exercise was similar for both drugs.