Abstract 653: SCN5A Mutation is Associated with Early and Frequent Recurrence of Ventricular Fibrillation in Patients with Brugada Syndrome
Mutation in SCN5A has been reported to be causally linked to Brugada syndrome (BrS), but recent observation revealed that this mutation is not necessarily associated with ventricular fibrillation (VF) or syncope episode in a case of BrS. We therefore examined the clinical importance of SCN5A mutation in BrS patients. Total 121 patients were examined. The existence of SCN5A mutation (n=14) was not associated with VF/syncope episode [SCN5A (+) vs SCN5A (−), 28.6% (4/14) vs 10.9% (10/92); P=NS]. ICD was implanted for secondary prevention (SP group) in 28 patients (54.9%) and for primary prevention n (PP group) in 23 of 51 patients (45.1%). During a mean follow-up period of 49.3 ± 33.7 months, 13 patients (46.4%) in SP group and 1 patient (4.3%) in PP group had received appropriate shocks. The shock free survival was significantly shorter in SP group than PP group (52.4% vs 88.9% at 5 years, p = 0.0016). Next, we examined SCN5A mutation on the recurrence of VF episode in SP group. The shock free survival was significantly shorter in BrS patients with SCN5A mutation than the patients without SCN5A mutation (0% vs. 76.4% at 1 years, p = 0.002, figure⇓). Moreover, the number of ICD shocks was significantly larger in BrS patients with SCN5A mutation than in BrS patients without SCN5A mutation (9.3 ± 6.4 vs. 1.7 ± 3.2, p = 0.001). VF inducibility by programmed electrical stimulation was not associated with shock free survival. SCN5A mutation is strongly associated with early and frequent VF recurrence. Additional medical management should be required in symptomatic BrS patients with SCN5A mutation.