Class 4 Antiarrhythmic Drugs: Verapamil and Diltiazem
Verapamil and diltiazem are non‑dihydropyridine calcium channel blockers classified as Class IV antiarrhythmics, primarily used to slow atrioventricular (AV) nodal conduction and control ventricular rate in supraventricular tachyarrhythmias such as atrial…
Antiarrhythmic drugs: Class III – Amiodarone and others
Class III antiarrhythmics predominantly prolong cardiac repolarization via potassium channel blockade, with amiodarone as the prototypical agent and additional options including dofetilide, sotalol, ibutilide, and dronedarone chosen based on structural heart disease,…
Antiarrhythmic drugs: Beta-adrenoceptor-blocking drugs (Class 2)
Introduction Among the diverse categories of drugs used to manage cardiac arrhythmias, beta-adrenoceptor-blocking drugs (beta blockers)—classified as Class 2 antiarrhythmics under the Vaughan Williams scheme—play a pivotal role in controlling aberrant…
Antiarrhythmic drugs: Propafenone (Class 1C)
Propafenone is a Class 1C antiarrhythmic that produces potent, use‑dependent blockade of fast cardiac Na+ channels with slow unbinding kinetics, resulting in marked conduction slowing and QRS widening, and it…
Antiarrhythmic drugs: Flecainide (Class 1C)
Flecainide is a Class 1C antiarrhythmic agent widely used for rhythm control in atrial and ventricular arrhythmias, particularly in patients without significant structural heart disease. The following summarizes its pharmacology, clinical…
Antiarrhythmic drugs: Mexiletine (Class 1B)
Mexiletine is an oral Class IB antiarrhythmic and sodium channel blocker structurally related to lidocaine, used primarily for ventricular arrhythmias and selected channelopathies such as LQT3 where late sodium current…
Antiarrhythmic drugs: Lidocaine (Class 1B)
If you trained in a time when every crash cart seemed to include “lido,” you remember lidocaine as the go-to antidote for ugly ventricular ectopy. Today, it has a more…
Antiarrhythmic drugs: Disopyramide (Class 1A)
Introduction Disopyramide is a Class 1a antiarrhythmic agent, primarily used in the treatment of ventricular tachycardia. It functions as a sodium channel blocker, inhibiting conduction by depressing the increase in…
Antiarrhythmic drugs: Quinidine (Class 1A)
Overview and Learning Objectives By the end of this chapter, you should be able to: Quinidine is a prototypical Class IA antiarrhythmic historically used in atrial and ventricular arrhythmias. Although…
Antiarrhythmic drugs: Procainamide (Class 1A)
Introduction Procainamide is a medication primarily used in the treatment of cardiac arrhythmias, which are irregular heart rhythms. It belongs to the class of antiarrhythmic agents known as Group I…
