Review : Sotalol: Current Status and Expanding Indications

Abstract

Background: The role of antiarrhythmic drug therapy continues to undergo major changes. The change is necessitated by the advent of invasive interventional procedures, such as catheter ablation of arrhythmias and the use of implantable devices for sensing and termi nating life-threatening ventricular arrhythmias and symptomatically troublesome supraven tricular arrhythmias. Many conventional and time-honored drugs, such as sodium channel blockers, have been found either to be ineffective or to have the potential to produce seri ous proarrhythmic reactions. Attention is therefore focused on compounds that prolong repolarization and reduce sympathetic stimulation. Two compounds, amiodarone and sotalol, have emerged as prototypes of drugs of the future.

Methods and Results: This review focuses on sotalol for controlling supraventricular and ventricular tachyarrhythmias. Sotalol is a major antiarrhythmic agent that combines potent class III action with nonselective β-blocking properties. The drug's pharmacokinetics is sim ple. Its elimination half-life is 10-15 hours, the drug being excreted almost exclusively by the kidneys. Sotalol's pharmacokinetics allows development of optimal dosing for initiation of therapy relative to changes in creatinine clearance with further dose adjustment by mon itoring the QT interval on the surface electrocardiogram. The compound exerts broad- spectrum antiarrhythmic actions in supraventricular and ventricular arrhythmias. It prevents inducible ventricular tachycardia (VT) and ventricular fibrillation (VF) in approximately 30% of patients with a higher figure for the suppression of spontaneously occurring arrhyth mias documented on Holter recordings.

Conclusions: The major role of sotalol is in the management of VT/VF often in conjunction with an implantable cardioverter/defibrillator, in which context it lowers the defibrillation threshold. Sotalol is superior to class I agents, especially in VT/VF and in survivors of car diac arrest. Sotalol has emerged as a major antifibrillatory compound for the control of life- threatening ventricular arrhythmias as the main indication. Data have indicated its poten tial for the maintenance of stability of sinus rhythm in patients with atrial fibrillation and flutter after electrical conversion and in preventing their occurrence in a variety of clinical settings.