In which class of the Vaughn-Williams classification system of anti-dysrhythmic medications does verapamil belong?
A) IA
B) IB
C) II
D) IV

Question

Quizplus · Accepted Answer

Verapamil belongs to class IV of the Vaughn-Williams classification system, which includes calcium channel blockers with predominantly negative chronotropic and inotropic effects on the heart. Verapamil specifically blocks L-type calcium channels in the myocardium, which results in decreased calcium influx and subsequent relaxation of vascular smooth muscle and decreased cardiac contractility. Class IV anti-dysrhythmics are primarily used for the treatment of supraventricular dysrhythmias, such as atrial fibrillation and atrial flutter.

In Which Class of the Vaughn-Williams Classification System of Anti-Dysrhythmic