Classification and pharmacology of antiarrhythmic drugs

Despite the emergence of several forms of nonpharmacologic therapy for card iac arrhythmias, antiarrhythmic drugs continue to play an important role in the management of patients with this common clinical problem. The key to t he proper use of antiarrhythmic drugs is a thorough knowledge of their mode of action and pharmacology. The pharmacology of antiarrhythmic drugs is pa rticularly important because patients with cardiac arrhythmias frequently h ave multiorgan disease, which may influence the metabolism and elimination of antiarrhythmic drugs. The accumulation of toxic amounts of these agents can lead to dire effects including, but not limited to, ventricular proarrh ythmia and malignant bradycardia. The goals of pharmacologic therapy of car diac arrhythmia are to provide the maximum benefit in terms of arrhythmia s uppression while maintaining patient safety. To accomplish these goals, a k nowledge of the pharmacology of several antiarrhythmic drugs is mandatory.