title: Characterization of repolarization in Brugada syndrome patients during exercise testing: Dynamic angle evaluation.
abstract: BACKGROUND
  A new ECG criterion has been studied in Brugada syndrome (BrS) at rest to differentiate type 2 and incomplete right bundle branch block (IRBBB).
  
  
  METHODS
  We assessed this criterion during exercise comparing BrS (46 patients) and IRBBB (17 patients). A beta angle was measured from lead V1 between the upslope of S-wave and the downslope of the r'-wave.
  
  
  RESULTS
  Beta angle was significantly larger in BrS at rest (58±24° vs 25±15°, p<0.001), exercise (47±26° vs 15±11°, p<0.001), and recovery (46±24° vs 21±12°, p<0.001) with a reduction in angle at exercise compared to rest. There was a significant rebound in angle at recovery in the control group to (p<0.001); no such rebound was observed in the BrS group (p=NS).
  
  
  CONCLUSIONS
  Beta angle study at rest and its evolution at exercise could help discriminate BrS patients from healthy subjects.
authors.affiliation: Dept of Rehabilitation and Coronary Disease, University Hospital of Bordeaux, Pessac, France. Electronic address: thomas.pospiech@u-bordeaux.fr.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pospiech
authors.affiliation: Dept of Rehabilitation and Coronary Disease, University Hospital of Bordeaux, Pessac, France; Division of Cardiology, Sport Clinic of Bordeaux, Merignac, France.
authors.forename: Jérémie
authors.initials: J
authors.lastname: Jaussaud
authors.affiliation: Dept of Electrophysiology, University Hospital of Bordeaux, LYRIC, Pessac, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Sacher
authors.affiliation: Bioengineering Institute, University of Auckland, Private Bag, Auckland, New Zealand.
authors.forename: Darren A
authors.initials: DA
authors.lastname: Hooks
authors.affiliation: Dept of Electrophysiology, University Hospital of Bordeaux, LYRIC, Pessac, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Haïssaguerre
authors.affiliation: Dept of Rehabilitation and Coronary Disease, University Hospital of Bordeaux, Pessac, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Douard
mesh_terms: D000465:Algorithms; D053840:Brugada Syndrome / Q000145:classification / Q000175:diagnosis*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D003937:Diagnosis, Differential; D004562:Electrocardiography / Q000379:methods*; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Brugada syndrome; Exercise testing; Incomplete RBBB; Repolarization