title: Effect of verapamil on prevention of atrial fibrillation in patients implanted with an implantable atrial defibrillator.
abstract: BACKGROUND
  The role of verapamil in the prevention of atrial fibrillation (AF) in patients with recurrent AF is unknown.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the effect of verapamil on the prevention of AF in patients implanted with an implantable atrial defibrillator (IAD).
  
  
  METHODS
  The effects of verapamil (240 mg/day) on the total duration of AF, number of AF recurrences, and number of cardioversions were prospectively evaluated in a randomized, crossover fashion over an 8-week period in 11 patients (9 men, 2 women; mean age: 60 +/- 6 years) implanted with an IAD.
  
  
  RESULTS
  Implantable atrial defibrillators successfully converted 13 of 14 (93%) spontaneous episodes of AF. There was no significant difference in the efficacy of cardioversion (86 vs. 100%, p = 0.8), the total duration of AF (173 +/- 198 vs. 270 +/- 241 h, p = 0.5), the number of AF episodes (8.5 +/- 9.0 vs. 9.3 +/- 10.2, p = 0.3), and the number of cardioversions (1.7 +/- 2.4 vs. 1.8 +/- 2.1 p = 0.7) with or without treatment with verapamil.
  
  
  CONCLUSIONS
  The results of the present study suggest that treatment with verapamil has no significant effect on the prevention of AF in patients treated with an LAD.
authors.affiliation: Division of Cardiology, Department of Medicine, University of Hong Kong, Queen Mary Hospital, Hong Kong, China.
authors.forename: H F
authors.initials: HF
authors.lastname: Tse
authors.forename: Q
authors.initials: Q
authors.lastname: Wang
authors.forename: C M
authors.initials: CM
authors.lastname: Yu
authors.forename: G M
authors.initials: GM
authors.lastname: Ayers
authors.forename: C P
authors.initials: CP
authors.lastname: Lau
mesh_terms: D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000517:prevention & control*; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D018592:Cross-Over Studies; D017147:Defibrillators, Implantable; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D014700:Verapamil / Q000627:therapeutic use*
chemical_list: D000889:Anti-Arrhythmia Agents; D002121:Calcium Channel Blockers; D014700:Verapamil