title: Ventricular fibrillation associated with complete right bundle branch block.
abstract: BACKGROUND
  A substantial number of patients with idiopathic ventricular fibrillation (IVF) present with no specific electrocardiographic (ECG) findings.
  
  
  OBJECTIVE
  To evaluate complete right bundle branch block (RBBB) in patients with IVF.
  
  
  METHODS
  Patients with IVF showing complete RBBB were included in the present study. Structural and primary electrical diseases were excluded, and provocation tests were performed to exclude the presence of spastic angina or Brugada syndrome (BrS). The prevalence of complete RBBB and the clinical and ECG parameters were compared either in patients with IVF who did not show RBBB or in the general population and age and sex comparable controls with RBBB.
  
  
  RESULTS
  Of 96 patients with IVF, 9 patients were excluded for the presence of BrS. Of 87 patients studied, 10 (11.5%) patients showed complete RBBB. None had structural heart diseases, BrS, or coronary spasms. The mean age was 44 ± 15 years, and 8 of 10 patients were men. Among the ECG parameters, only the QRS duration was different from that of the other patients with IVF who did not show complete RBBB. Ventricular fibrillation recurred in 3:2 in the form of storms, which were well suppressed by isoproterenol. Complete RBBB was found less often in control subjects (1.37%; P < .0001), and the QRS duration was more prolonged in patients with IVF: 139 ± 10ms vs 150 ± 14ms (P = .0061).
  
  
  CONCLUSIONS
  Complete RBBB exists more often in patients with IVF than in controls. A prolonged QRS complex suggests a conduction abnormality. Our findings warrant further investigation of the role of RBBB in the development of arrhythmias in patients with IVF.
authors.affiliation: Department of Cardiology, School of Medicine, Keio University, Tokyo, Japan. yoshiyaaizawa-circ@umin.ac.jp
authors.forename: Yoshiyasu
authors.initials: Y
authors.lastname: Aizawa
authors.forename: Seiji
authors.initials: S
authors.lastname: Takatsuki
authors.forename: Takehiro
authors.initials: T
authors.lastname: Kimura
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Nishiyama
authors.forename: Kotaro
authors.initials: K
authors.lastname: Fukumoto
authors.forename: Yoko
authors.initials: Y
authors.lastname: Tanimoto
authors.forename: Kojiro
authors.initials: K
authors.lastname: Tanimoto
authors.forename: Shunichiro
authors.initials: S
authors.lastname: Miyoshi
authors.forename: Makoto
authors.initials: M
authors.lastname: Suzuki
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Yokoyama
authors.forename: Masaomi
authors.initials: M
authors.lastname: Chinushi
authors.forename: Ichiro
authors.initials: I
authors.lastname: Watanabe
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ogawa
authors.forename: Yoshifusa
authors.initials: Y
authors.lastname: Aizawa
authors.forename: Charles
authors.initials: C
authors.lastname: Antzelevitch
authors.forename: Keiichi
authors.initials: K
authors.lastname: Fukuda
mesh_terms: D000328:Adult; D000368:Aged; D002037:Bundle-Branch Block / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D014693:Ventricular Fibrillation / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D055815:Young Adult