Bepridil for Persistent Atrial Fibrillation

Abstract

Bepridil was originally developed as an anti-angina drug which suppresses mainly L and T type calcium channels, several potassium channels, and fast kinetic sodium channel of the myocardial cells. Bepridil has been used for restoring sinus rhythm and maintenance of sinus rhythm in patients with long-lasting atrial fibrillation in Japan. Atrial fibrillation has been converted to sinus rhythm within a few months in majority of patients with persistent atrial fibrillation by bepridil. Fibrillation waves gradually become coarser, after that sinus rhythm has been restored. Pharmacological cardioversion with bepridil recovered atrial mechanical function earlier than electrical cardioversion. In other words, bepridil improved atrial stunning from the early phase of post-cardioversion. Bepridil was highly effective for maintenance of sinus rhythm after pharmacological or electrical conversion. The serum concentration of bepridil is higher in patients with successful maintenance of sinus rhythm than in patients with recurrent atrial fibrillation. The combination therapy with Na channel blocker is effective. Bepridil is more effective for maintenance of sinus rhythm in patients with large left atrial diameter and with or without structural heart disease than Na channel blocker. Care should be taken for torsades de pointes or ventricular fibrillation caused by QT prolongation during bepridil treatment. Pulmonary fibrosis also occurred in a very few percentage of patients with bepridil. However, bepridil is the most effective antiarrhythmic drug for conversion to sinus rhythm in patients with persistent atrial fibrillation.