New antiarrhythmic drugs for the treatment of atrial fibrillation

Abstract

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice and a difficult-to-treat arrhythmia. Conventional antiarrhythmic drugs, including flecainide, propafenone, sotalol and amiodarone, have several limitations in terms of efficacy and tolerability, and have made new drug development crucial. In the last decade, intensive research was undertaken to find new pharmacological options for the treatment of AF, and two new drugs are now available. Vernakalant is an atrial-selective drug specifically designed to block sodium channels at the atrial level, and its intravenous formulation has recently been recommended for approval by the Food and Drug Administration for pharmacological conversion of AF. Dronedarone is a chemical derivative of amiodarone (though having a significantly different clinical profile) with effects on multiple ion channels that proved effective in reducing the rate of the combined endpoint of death from any cause and cardiovascular hospitalization in patients with non-permanent AF enrolled in the ATHENA study. The available evidence on the efficacy of dronedarone has led to approval for recommendation in many clinical situations in which rhythm control is desirable. The complexity of the mechanisms underlying AF and the large variability of associated comorbidities render the AF patient a unique entity, making the identification of patients who may benefit from these novel approaches challenging.