title: Mode of onset of ventricular fibrillation in patients with early repolarization pattern vs. Brugada syndrome.
abstract: OBJECTIVE
  The aim of the present study was to identify specific electrocardiogram (ECG) features that predict the development of multiple episodes of ventricular fibrillation (VF) in patients with an early repolarization (ER) pattern and to compare the mode of VF initiation with that observed in typical cases of Brugada syndrome (BrS).
  
  
  RESULTS
  The mode of the onset and the coupling intervals of the premature ventricular contractions (PVCs) initiating VF episodes were analysed in patients with BrS (n = 8) or ER who experienced sudden cardiac death/syncope or repeated appropriate implantable cardioverter defibrillator shocks. Among the 11 patients with ER, 5 presented with electrical storm (ES, four or more recurrent VF episodes/day). The five ES patients displayed a dramatic but very transient accentuation of J waves across the precordial and limb leads prior to the development of ES. Ventricular fibrillation episodes were more commonly initiated by PVCs with a short-long-short (SLS) sequence in ER (42/58, 72.4%) vs. BrS patients (13/86, 15.1%, P < 0.01). Coupling intervals were significantly shorter in the ER group compared with those with BrS [328 (320, 340) ms vs. 395 (350, 404) ms, P < 0.01].
  
  
  CONCLUSIONS
  Our study provides additional evidence in support of the hypothesis that ER pattern in the ECG is not always benign. Transient augmentation of global J waves may be indicative of a highly arrhythmogenic substrate heralding multiple episodes of VF in patients with ER pattern. Ventricular tachycardia/VF initiation is more commonly associated with an SLS sequence, and PVCs display a shorter coupling interval in patients with ER pattern compared with those with BrS.
authors.affiliation: Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, 138-736 Poongnap-dong 388-1, Songpa-gu, Seoul, Republic of Korea. gbnam@amc.seoul.kr
authors.forename: Gi-Byoung
authors.initials: GB
authors.lastname: Nam
authors.forename: Kwan-Ho
authors.initials: KH
authors.lastname: Ko
authors.forename: Jun
authors.initials: J
authors.lastname: Kim
authors.forename: Kyoung-Min
authors.initials: KM
authors.lastname: Park
authors.forename: Kyoung-Suk
authors.initials: KS
authors.lastname: Rhee
authors.forename: Kee-Joon
authors.initials: KJ
authors.lastname: Choi
authors.forename: You-Ho
authors.initials: YH
authors.lastname: Kim
authors.forename: Charles
authors.initials: C
authors.lastname: Antzelevitch
mesh_terms: D000328:Adult; D000368:Aged; D053840:Brugada Syndrome / Q000150:complications* / Q000628:therapy; D002304:Cardiac Pacing, Artificial; D002316:Cardiotonic Agents / Q000627:therapeutic use; D016022:Case-Control Studies; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007545:Isoproterenol / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D014693:Ventricular Fibrillation / Q000209:etiology* / Q000628:therapy; D055815:Young Adult
chemical_list: D002316:Cardiotonic Agents; D007545:Isoproterenol