Acute Management of Ventricular Arrhythmias: Role of Antiarrhythmic Agents

Abstract

When treating life‐threatening ventricular arrhythmias such as symptomatic ventricular tachycardia and ventricular fibrillation (VT/VF), the nature of the arrhythmia must be precisely defined and the approach must be tailored to it. For hemodynamically unstable ventricular arrhythmias, DC cardioversion or high‐energy defibrillation remains the approach of choice. Determining the specific role of intravenous drugs in acute conversion of VT/VF and the most appropriate long‐term therapy (pharmacologic or nonpharmacologic) to prevent recurrence can be difficult. Pharmacologic conversion of stable VT/VF presents an even greater challenge, as the role of lidocaine, considered the first‐line agent for many decades, is now being reevaluated. Lidocaine appears to be effective in converting no more than 20% of stable VTs, compared with 70% for intravenous sotalol. The precise efficacies of parenteral procainamide, β‐blockers, and newer class III agents, including intravenous amiodarone, remain to be defined; however, intravenous amiodarone, available recently, can control unstable, recurrent VT/VF that is resistant to lidocaine or procainamide. A standard regimen of concomitant intravenous and oral amiodarone may be given for rapid and sustained control, and allows oral amiodarone to be continued in a significant number of patients.