title: Quantitative assessment of cibenzoline administration for vagally mediated paroxysmal atrial fibrillation using frequency-domain heart rate variability analysis.
abstract: BACKGROUND
  Cibenzoline (CBZ), a class I antiarrhythmic drug, has been widely used to maintain sinus rhythm in patients with paroxysmal atrial fibrillation (P-AF). This agent has an anticholinergic action and will become the drug of first choice for vagally mediated P-AF. We assessed its efficacy quantitatively by analyzing the frequency-domain heart rate variability (FD-HRV) of the Holter electrocardiogram (ECG) in patients with vagal P-AF.
  
  
  METHODS
  We enrolled 65 consecutive patients with vagal P-AF, but 31 patients were excluded because of the occurrence of significant arrhythmias during the 24-h Holter recordings. Accordingly, CBZ was administered to the remaining 34 patients. After administration, a Holter ECG recording was made again. High frequency (HF) components, i.e., vagal tone index, on the FD-HRV analysis from 00:00 h to 06:00 h were used for assessment. In 14 patients, the treatment was changed to disopyramide (DSP) and the same analyses were performed.
  
  
  RESULTS
  In two patients, the FD-HRV analysis was not utilized after administration. Finally, 32 patients were available for evaluation. CBZ was considered effective for vagal P-AF in 24 patients (75%). After administration, the HF component levels decreased (1589+/-795 ms(2) vs. 850+/-524 ms(2), p<0.0001). Comparison of the pre-administration HF component levels between the CBZ-responsive group and the CBZ-non-responsive group showed higher levels in the CBZ-responsive group (1766+/-758 ms(2) vs. 1058+/-690 ms(2), p=0.026). Although no significant difference in the reduction of the HF component levels was found between CBZ and DSP, DSP had anticholinergic side effects in two patients (14%).
  
  
  CONCLUSIONS
  In vagal P-AF patients, larger HF components on the FD-HRV analysis could be a hallmark of the antiarrhythmic action of CBZ. The reduction in the HF component levels after drug administration is useful for a quantitative assessment of anticholinergic action.
authors.affiliation: Second Department of Internal Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-8611, Japan.
authors.forename: Mutsumi
authors.initials: M
authors.lastname: Miyakoshi
authors.forename: Takanori
authors.initials: T
authors.lastname: Ikeda
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Miwa
authors.forename: Katsura
authors.initials: K
authors.lastname: Sakaki
authors.forename: Haruhisa
authors.initials: H
authors.lastname: Ishiguro
authors.forename: Atsuko
authors.initials: A
authors.lastname: Abe
authors.forename: Takehiro
authors.initials: T
authors.lastname: Tsukada
authors.forename: Hisaaki
authors.initials: H
authors.lastname: Mera
authors.forename: Satoru
authors.initials: S
authors.lastname: Yusu
authors.forename: Hideaki
authors.initials: H
authors.lastname: Yoshino
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000188:drug therapy*; D018680:Cholinergic Antagonists / Q000627:therapeutic use; D004206:Disopyramide / Q000627:therapeutic use; D015716:Electrocardiography, Ambulatory; D005260:Female; D006339:Heart Rate; D006801:Humans; D007093:Imidazoles / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents; D018680:Cholinergic Antagonists; D007093:Imidazoles; D004206:Disopyramide; C032151:cifenline