Abstract 14948: Clinical Characteristics of Idiopathic Ventricular Fibrillation with Early Repolarization and Response of Early Repolarization to Sodium Channel Blocker: Comparison to Brugada Syndrome with Ventricular Fibrillation.
Background: Recent studies have shown a high incidence of early repolarization (J-point elevation) in inferolateral leads in patients with idiopathic ventricular fibrillation (IVF). Brugada syndrome (BS) is also characterized by J-point and ST elevation in right precordial leads and VF. However little is known about similarities and differences between IVF with early repolarization (Early Repolarization Syndrome: ERS) and BS.
Methods: Fourteen patients of ERS and twenty-one patients of BS with documented VF were included into this study. Early repolarization was defined as an elevation of the J-point (QRS-ST junction) of at least 0.1mv from baseline in inferior or lateral leads. All patients experienced VF which was confirmed in electrocardiography (ECG) or monitor ECG and follow up data was collected from implantable cardioverter defibrillator (ICD). To distinguish precisely between ERS and BS, provocative tests with sodium-channel blockers were performed in all ERS and BS patients.
Results: In ERS group, all patients were male and most patients experienced ventricular fibrillation during sleep or low activity (79%). Most patients in ERS group (92%) and BS group (100%) showed attenuation of ER in inferior or lateral leads by sodium channel blocker infusion (94%). Comparing to patients in BS group, ERS patients showed lower inducibility of VF during electrophysiological study (0% vs. 88% p<0.05) and low positivity in signal averaged electrocardiography (SAECG) (7% vs. 60% p<0.01). Moreover, ERS group appeared to have a significantly lower recurrence of VF than BS group (7% vs. 52% p<0.01) .
Conclusions: Unlike ST elevation in right precordial lead in BS, early repolarization in inferior or lateral leads in both ERS and BS patients were attenuated by sodium channel blocker infusion. ERS group showed peculiar clinical characteristics such as negative late potentials, low VF inducibility and appeared to have a better prognosis than Brugada syndrome.
- © 2010 by American Heart Association, Inc.