Verapamil and the heart: Pharmacological and Therapeutic Considerations

Abstract

Verapamil is a new anti-anginal and anti-arrhythmic drug whose pharmacological actions can be related to its specific blocking effect on the transmembrane transport of calcium ions. Intravenous verapamil slows the ventricular rate in atrial fibrillation and flutter with an occasional patient reverting to sinus rhythm. The drug promptly terminates most cases of paroxysmal supraventricular tachycardias. It is likely to become the initial agent of choice in the acute treatment of this arrhythmia. Verapamil is not effective in ventricular tachycardia or in atrial fibrillation complicating the WPW syndrome. Few side effects are encountered following intravenous verapamil expecially when the drug is given slowly. Verapamil is also effective in angina in a dose of 120mg tds orally. Little is known of the metabolism and pharmacokinetic of verapamil but the available experience in arrhythmias clearly justifies further study.