Beta adrenergic blocking agents for exertional angina pectoris

Beta adrenergic blocking agents are effective antianginal agents and reduce the frequency of anginal attacks, nitroglycerin consumption, and improve exercise tolerance in patients with stable exertional angina pectoris. These drugs are effective in the management of exertional angina pectoris primarily due to their ability to block beta 1 receptors and thereby competitively blocking the effects of sympathetic stimulation (i.e. increase in myocardial oxygen demand) during exercise. In this report other pharmacological properties of these agents i.e. membrane stabilizing activity, intrinsic sympathomimetic activity and cardioselectivity are of little importance. Comparative studies with beta adrenergic blocking agents with different ancillary properties, utilizing intravenous preparations, acute single and multiple oral dosing and sustained oral therapy prescribed for several weeks or months, show that if used in equipotent doses all beta adrenergic blocking agents are equally effective antianginal agents. It should be recognized that therapy with these agents may precipitate heart failure or aggravate bronchospasm in susceptible patients. This can occur with cardioselective agents and with beta blockers which also have intrinsic sympathomimetic activity.