Despite the surfacing of several forms of non-pharmacologic therapy for cardiac arrhythmias, antiarrhythmic drugs keep up to play an important role in the management of patients with this common clinical problem. The key to the actual use of antiarrhythmic drugs is a thorough knowledge of their mode of action and pharmacology. The pharmacology of antiarrhythmic drugs is especially important because patients with cardiac arrhythmias frequently have multiorgan disease, which may influence the metabolism and elimination of antiarrhythmic drugs. The cumulation of toxic amounts of these agents can lead to direct effects including, but not restricted to, ventricular proarrhythmia and malignant bradycardia. The main aims of pharmacologic therapy of cardiac arrhythmia are to aasemble the maximum benefit in terms of arrhythmia suppression while maintaining patient safety. To accomplish these goals, knowledge of the pharmacology of various antiarrhythmic drugs is necessary.
