Lege Artis Medicinae

[Effects of verapamil on cardiac arrhythmias]

ZÁMOLYI Károly1

JUNE 30, 1992

Lege Artis Medicinae - 1992;2(01 KLSZ)

[Verapamil, a „first generation" calcium anta gonist and synthetic papaverine derivate, was initially introduced as a potent peripheral and coronary vasodilator. It was later found to have significant antiarrhythmic activity, the mechanism of which was related to selective inhibition of transmembrane fluxes of the calcium. The electrical activity of the sinus node and of the atrioventricular (AV) node depends primarily on slow inward Ca2+ currents, therefore it is logical to expect that calcium antagonists will be effective here. The main electrophysiologic effects of verapamil include the slowing of conduction and the prolongation of refractoriness in the atrio ventricular node without significantly affecting intraatrial or intraventricular conduction. Thus, verapamil has been effective in the acute termination of reentry tachycardia in volving the atrioventricular node and in slowing the ventricular response during atrial fibrillation or flattern. Since verapamil has little, if any, effect on the electrical activity of the ventricle or the His Purkinje system, it does not provide effective therapy for controlling ventricular tachycardias. This paper focuses on a detailed discussion of the various arrhythmias that respond to calcium antagonist therapy. ]

AFFILIATIONS

  1. Orvostovábbképző Egyetem II. Belgyógyászati Klinika Budapest

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