Bepridil for drug-refractory ventricular tachyarrhythmias

To avoid frequent discharges of implantable cardioverter defibrillators, antiarrhythmic drugs may be needed in some patients with ventricular tachyarrhythmias. For ventricular tachyarrhythmias refractory to conventional antiarrhythmic drugs, we evaluated the efficacy of bepridil, a multiple ion-channel blocker.

Sixteen patients with structural heart disease and ventricular tachyarrhythmias refractory to multiple antiarrhythmic drugs (4.1+/-1.6 drugs including class III drugs) were enrolled. Bepridil was prescribed at a mean dose of 156+/-40 mg/day. Bepridil prolonged the QT/QTc interval without affecting heart rate or the QRS duration. During a mean follow-up of 52+/-44 months, bepridil completely suppressed ventricular tachyarrhythmias in 6 of the 16 patients (38%) and the drug decreased the frequency of ventricular tachyarrhythmia recurrences by >75% in 3 of the other 10 patients. The markers of complete suppression of ventricular tachyarrhythmias during bepridil treatment included a smaller number of VT morphologies, a better NYHA functional class, and a greater drug-induced prolongation of the QT/QTc interval. The result of electrophysiologic study-guided evaluation of bepridil was closely associated with the clinical efficacy of bepridil in 7 of 8 patients.

Bepridil appears to be useful to suppress drug-refractory ventricular tachyarrhythmia recurrence.