Abstract 13936: Efficacy of Bepridil to Prevent Ventricular Fibrillation in Early Repolarization Syndrome
Background: Early repolarization syndrome is a new disease entity characterized by ventricular fibrillation in the absence of structural heart abnormalities and the early repolarization pattern in the electrocardiogram. Implantable cardioverter defibrillator is the only proven effective treatment to prevent sudden cardiac death, but arrhythmia recurrence is not rare and additional therapy is often required in early repolarization syndrome. Although quinidine has been effective in preventing ventricular fibrillation, up to one third of patients cannot tolerate quinidine because of sideeffects. This study aimed to identify the effective antiarrhythmic treatment in early repolarization syndrome.
Methods and Results: This study included 55 patients with early repolarization syndrome (age, 44±17 years; 7 women, 13%). All patients had events associated with ventricular fibrillation, and 14 patients (25%) had atrial fibrillation. During a follow up of 3.5±3.4 years, arrhythmia recurred in 11 patients (20%) (incidence, 6.5 per 100 person-years [95% confidence interval, 2.8-10.1]). Bepridil was effective in preventing ventricular fibrillation in three patients who had multiple recurrences including two patients who had repetitive arrhythmia episodes within a short-time, so called “electrical storm”. Notably, prior to bepridil, quinidine failed to control arrhythmias in two of the three patients. Bepridil did not result in the augmentation of early repolarization pattern in any of the patients. Lidocaine, procainamide, flecainide, propafenone, mexiletine, sotalol, and nifekalant were not effective for recurrences of arrhythmias. In three patients in whom bepridil was effective in acute treatment, the drug was continued. There was no arrhythmia recurrence in two patients during 3.8 years and 2 months, respectively, and the frequency of ventricular fibrillation was dramatically decreased in the remaining patient. Furthermore, bepridil was also effective in preventing atrial fibrillation in one patient.
Conclusion: Bepridil was effective in preventing recurrences of ventricular fibrillation in patients with early repolarization syndrome, and may be useful even in patients whose arrhythmias are refractory to quinidine.
- © 2013 by American Heart Association, Inc.