title: Predictors of atrial tachyarrhythmias in subjects with type 1 ECG pattern of Brugada syndrome.
abstract: BACKGROUND
  Previous studies have demonstrated a high incidence of atrial tachyarrhythmias (ATs) in patients with Brugada syndrome (BS). The present study aimed to investigate whether various 12-lead electrocardiogram (ECG) and electrophysiological parameters may help to differentiate subjects with a high probability to develop ATs.
  
  
  RESULTS
  The clinical records of 38 individuals (31 males, age 44.4 +/- 13.9) with spontaneous (n = 15) or ajmaline-induced (n = 23) type 1 ECG pattern of BS were analyzed. During a mean follow-up period of 4.6 +/- 2.2 years, nine subjects suffered ATs (24%). Six subjects displayed paroxysmal atrial fibrillation and three typical atrial flutter. Among the studied 12-lead ECG parameters, subjects with ATs exhibited increased values of P-wave duration in lead II, P-wave dispersion, PR interval in leads II, QRS duration in leads II and V(2), Tpeak-end interval in lead II, and Tpeak-end dispersion of the 12 leads in relation to those without ATs (P < 0.05). Among the assessed electrophysiological parameters, atrial-His (AH) and His-ventricular (HV) intervals were significantly prolonged in subjects with ATs (P < 0.05). Multiple Cox proportional hazards analysis revealed that P-wave duration in lead II, P-wave dispersion, Tpeak-end in lead II, Tpeak-end dispersion of the 12 leads, as well as AH and HV intervals are independent predictors of ATs in subjects with BS (P < 0.05). Cut-off point analysis showed that an HV interval>or=56 ms displayed the highest predictive ability (P < 0.01).
  
  
  CONCLUSIONS
  Our findings demonstrate that simple 12-lead ECG and electrophysiological parameters may easily be applied to identify high-risk subjects with BS ECG phenotype to develop ATs.
authors.affiliation: Arrhythmia Service, Herz-Zentrum, Bad Krozingen, Germany. k.letsas@mail.gr
authors.forename: Konstantinos P
authors.initials: KP
authors.lastname: Letsas
authors.forename: Reinhold
authors.initials: R
authors.lastname: Weber
authors.forename: Klaus
authors.initials: K
authors.lastname: Astheimer
authors.forename: Constantinos C
authors.initials: CC
authors.lastname: Mihas
authors.forename: Jochem
authors.initials: J
authors.lastname: Stockinger
authors.forename: Thomas
authors.initials: T
authors.lastname: Blum
authors.forename: Dietrich
authors.initials: D
authors.lastname: Kalusche
authors.forename: Thomas
authors.initials: T
authors.lastname: Arentz