Abstract 4628:Efficacy of Bepridil in Patients with Symptomatic Brugada Syndrome-The Relationship Between The Effects of Bepridil and SCN5A Mutation-
Background: It has been reported that Bepridil prevents ventricular fibrillation (VF) in patients with symptomatic Brugada syndrome (BrS) because it depresses Ito current. But the relationship between the effects of Bepridil and SCN5A mutation in patients with BrS is not known.
Methods and Results: Low-dose (100mg/day) Bepridil was administered for seven patients (three with SCN5A mutation, four without SCN5A mutation; all men; age, 33 to 74 years) of BrS. If the effect was insufficient, Bepridil was escalated to 200mg/day. Three patients with SCN5A mutation had many VF episodes (patient A 22/72, B 11/38 and C 10/26; VF events/months) before low-dose Bepridil. But after low-dose Bepridil, most VF episodes were controlled (patient A 0/27, B 1/30 and C 1/29; VF events/months). All of four patients (patient D, E, F and G) without SCN5A mutation had relapses of VFs in a short term after low-dose Bepridil. One patient (patient E) suspected to have proarrhythmia needed cessation of Bepridil. In the other three patients, 200mg/day of Bepridil was administered. It was effective for one patient (patient G), but not effective for the other two patients (patient D and F). In patients with SCN5A mutation, parameters of signal-averaged electrocardiography (SAECG) were improved after low-dose Bepridil. But there was no improvement in SAECG of patients without SCN5A mutation (figure⇓).
Conclusion: In patients of BrS with SCN5A mutation, low-dose Bepridil improved parameters of SAECG and controlled VF occurrence.