Abstract 2311: New Predictors of Arrhythmic Event in Brugada Syndrome: Manifest T-wave Alternans after Sodium Channel Blocker Administration
(Background) T-wave alternans is a major predictor for cardiac sudden death in several heart diseases. Manifest T-wave alternans (MTWA) is sometimes observed after a sodium channel blocker administration in Brugada syndrome (BS), but little is known about the occurrence of MTWA and clinical characteristics in patients with Brugada syndrome.
(Methods and Results) We administered pilsicainide chloride, a class Ic sodium channel blocker, to total 84 BS patients (age 48.0 years, 1 female). Clinical ventricular fibrillation (VF) was documented in 12 patients. Predictive indices for VF occurrence, including family history of sudden death, late potentials (LP), SCN5A mutation, induction of VF during EP study, and MTWA were examined. MTWA was not observed before pilsicainide administration, but became apparent in 14 patients 5 minutes after administration (Fig⇓.). MTWA positive patients had significantly a higher prevalence of VF (50% vs. 7.1%, P<0.001). In univariate analysis, LP also had significant predictive value (P=0.003), however in multivariate analysis, MTWA appeared the only independent predictor for VF occurrence (P=0.009).
(Conclusion) MTWA after pilsicainide administration is associated with the high risk for the VF occurrence.