title: Prognostic significance of early repolarization in inferolateral leads in Brugada patients with documented ventricular fibrillation: a novel risk factor for Brugada syndrome with ventricular fibrillation.
abstract: BACKGROUND
  Little is known about the clinical and prognostic impact of early repolarization (ER) on patients with Brugada syndrome (BrS), especially those with documented ventricular fibrillation (VF).
  
  
  OBJECTIVE
  To investigate the prevalence and prognostic significance of ER in inferolateral leads in patients with BrS and documented VF.
  
  
  METHODS
  We investigated 10 different 12-lead electrocardiograms (ECGs) recorded on different days to identify the presence of ER, which was defined as J-point elevation ≥0.1 mV in inferior (II, III, aVF) or lateral leads (I, aVL, V₄-V₆), in 49 individuals (46 men; age 46 ± 13 years) with a type 1 ECG of BrS and previous history of VF.
  
  
  RESULTS
  ER was observed persistently (in all ECGs) in 15 patients (31%; P group), intermittently (in at least one but not in all ECGs) in 16 patients (33%; I group), and not observed in 18 patients (37%; N group), yielding an overall ER incidence of 63% (31/49). During the follow-up period (7.7 years), recurrence of VF was documented in all 15 patients (100%) in the P group, and less in 12 patients (75%) in the I group and in 8 patients (44%) in the N group. The P group showed a worse prognosis than N group (P = .0001) by Kaplan-Meier analysis. Either persistent or intermittent ER in an inferolateral lead was an independent predictor of fatal arrhythmic events (hazard ratio 4.88, 95% confidence interval 2.02-12.7, P = .0004; and hazard ratio 2.50, 95% confidence interval 1.03-6.43, P = .043, respectively).
  
  
  CONCLUSIONS
  The prevalence of ER in inferolateral leads was high and an especially persistent form of ER was associated with a worse outcome in BrS patients with documented VF.
authors.affiliation: Division of Arrhythmia and Electrophysiology, Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center, Suita, Japan.
authors.forename: Hiro
authors.initials: H
authors.lastname: Kawata
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Morita
authors.forename: Yuko
authors.initials: Y
authors.lastname: Yamada
authors.forename: Takashi
authors.initials: T
authors.lastname: Noda
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Satomi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Aiba
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Isobe
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nagase
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Nakamura
authors.forename: Kengo
authors.initials: K
authors.lastname: Fukushima Kusano
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ito
authors.forename: Shiro
authors.initials: S
authors.lastname: Kamakura
authors.forename: Wataru
authors.initials: W
authors.lastname: Shimizu
mesh_terms: D000328:Adult; D000368:Aged; D053840:Brugada Syndrome / Q000503:physiopathology*; D003645:Death, Sudden; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011379:Prognosis; D012307:Risk Factors; D016019:Survival Analysis; D014693:Ventricular Fibrillation / Q000503:physiopathology*; D055815:Young Adult
keywords: BrS; Brugada syndrome; ECG; ER; Early repolarization; ICD; IVF; Idiopathic ventricular fibrillation; J wave; PES; RV; SCD; Sudden death; VF; early repolarization; electrocardiogram; idiopathic ventricular fibrillation; implantable cardioverter-defibrillator; programmed electrical stimulation; right ventricle; sudden cardiac death; ventricular fibrillation