title: Characteristics of induced ventricular fibrillation cycle length in symptomatic Brugada syndrome patients.
abstract: BACKGROUND
  Limited information is available on the ventricular fibrillation (VF) spectrum in Brugada syndrome (BS) patients. We clarified differences in the VF cycle length (CL) using fast-Fourier transformation (FFT) analysis in symptomatic and asymptomatic BS patients.
  
  
  RESULTS
  VF was induced by pacing from the right ventricular (RV) apex and/or RV outflow tract (RVOT) for >8s. A 4096-point FFT analysis of results from 28 male BS patients (51.1 ± 13.7 years old) was performed. Dominant frequency (DF) from phases 1 (4s) to 6 was obtained at 2-s intervals. The average DF from surface and intracardiac electrograms (ECG: DF(ECG); ICE: DF(ICE,), respectively) was compared between symptomatic and asymptomatic patients. Symptomatic patients had a significantly shorter effective refractory period at a CL of 600 ms at the RVOT than asymptomatic patients. DF(ECG) significantly increased with phase (5.64 ± 0.32 Hz in phase 1 to 6.16 ± 0.52 Hz in phase 6) and was significantly higher in symptomatic patients than in asymptomatic patients. DF(ICE) had the same characteristics as DF(ECG).
  
  
  CONCLUSIONS
  Induced VF in BS patients can be characterized using FFT analysis. Our data support the hypothesis that symptomatic patients have a significantly shorter VF CL than asymptomatic patients.
authors.affiliation: Division of Cardiology, Department of Medicine and Clinical Science, Yamaguchi University Graduate School of Medicine, Ube, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hiratsuka
authors.forename: Akihiko
authors.initials: A
authors.lastname: Shimizu
authors.forename: Takeshi
authors.initials: T
authors.lastname: Ueyama
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yoshiga
authors.forename: Masahiro
authors.initials: M
authors.lastname: Doi
authors.forename: Toshihide
authors.initials: T
authors.lastname: Ohmiya
authors.forename: Masaaki
authors.initials: M
authors.lastname: Yoshida
authors.forename: Masakazu
authors.initials: M
authors.lastname: Fukuda
authors.forename: Masunori
authors.initials: M
authors.lastname: Matsuzaki
mesh_terms: D000328:Adult; D053840:Brugada Syndrome / Q000503:physiopathology*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D005583:Fourier Analysis; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D014693:Ventricular Fibrillation / Q000503:physiopathology*