Effects of acebutolol on chronic stable angina pectoris. A placebo-controlled, double-blind, randomized crossover study
We evaluated the effects of acebutolol, a cardioselective β-adrenergic blocking agent, on the anginal pattern and exercise tolerance in 44 patients with chronic stable angina. There were 43 males and one female, with a mean age of 57 years (range 48-73 years). The study consisted of an initial 4-week, single-blind placebo control phase, followed by a 3-week, single-blind dose-titration phase using increasing doses of acebutolol and by two 5-week double-blind phases that included randomization to acebutolol or placebo and crossover. A 1-week withdrawal schedule followed each treatment phase. All patients kept a diary of anginal frequency and nitroglycerin consumption. Capsule counts of returned medication were made at each visit. Exercise treadmill tests were performed at entry into the study and on the final day of each of the four phases. Acebutolol produced a significant decrease in the frequency of angina attacks, consumption of nitroglycerin and exercise capacity. Resting and peak exercise values were significantly reduced. Heart rates were reduced by 16% and 18%, respectively (p < 0.002) and rate-pressure products by 17% and 30%, respectively (p < 0.002). At effective antianginal dosages, acebutolol had no significant adverse effects on pulmonary functions. No clinical side effects of acebutolol necessitated drug discontinuance. Acebutolol is a well-tolerated β-blocking drug that significantly reduces spontaneous anginal frequency, decreases consumption of nitroglycerin and increases exercise capacity in patients with chronic stable angina. It is a useful therapeutic addition to the group of β-adrenergic blocking agents. Further, its lack of deleterious effects on the bronchial smooth muscle suggest that acebutolol may be safely used in patients in whom angina is associated with obstructive pulmonary disease.
DiBianco, R., Singh, S., Singh, J., Katz, R., Bortz, R., Gottdiener, J., Spodick, D., Laddu, A., & Fletcher, R. (1980). Effects of acebutolol on chronic stable angina pectoris. A placebo-controlled, double-blind, randomized crossover study. Circulation, 62 (6 I). http://dx.doi.org/10.1161/01.CIR.62.6.1179