title: Comparison of verapamil and ibutilide for the suppression of immediate recurrences of atrial fibrillation after transthoracic cardioversion.
abstract: BACKGROUND
  Verapamil and ibutilide blunt the atrial fibrillation-induced shortening of atrial refractoriness that may predispose to an immediate recurrence of atrial fibrillation after cardioversion. This study compared the efficacy of verapamil and ibutilide in preventing an immediate recurrence of atrial fibrillation.
  
  
  RESULTS
  Transthoracic cardioversion was performed in 223 patients with atrial fibrillation. Atrial fibrillation recurred within 10 minutes after cardioversion on two occasions in 21 patients (9.4%). Twenty of these patients were randomly assigned to receive an infusion of either 0.15 mg/kg of verapamil at a rate of 2 mg/min (11 patients), or 1 mg of ibutilide over 10 minutes (9 patients). Eight patients (73%) had another episode of immediate recurrence of atrial fibrillation after verapamil, compared to two patients (22%) after ibutilide (P<0.05). Including the results after crossover, immediate recurrence of atrial fibrillation occurred in 8 of 12 patients (67%) who received verapamil, compared to 3 of 16 patients (19%) who received ibutilide (P=0.02). Verapamil and/or ibutilide successfully prevented immediate recurrence of atrial fibrillation in 17 of 20 patients (85%). After 700 days of follow-up, there was no significant difference in the recurrence rate of atrial fibrillation between the patients in whom immediate recurrence of atrial fibrillation was prevented by verapamil and/or ibutilide and the patients who were successfully converted to sinus rhythm and did not have immediate recurrence of atrial fibrillation.
  
  
  CONCLUSIONS
  Ibutilide is more effective than verapamil in preventing immediate recurrence of atrial fibrillation. Suppression of immediate recurrence of atrial fibrillation by ibutilide and/or verapamil may allow for long-term maintenance of sinus rhythm postcardioversion as often as in patients who do not experience immediate recurrence of atrial fibrillation.
authors.affiliation: Division of Cardiology, Department of Internal Medicine, University Hospital Benjamin Franklin, Free University of Berlin, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Sticherling
authors.forename: Mehmet
authors.initials: M
authors.lastname: Ozaydin
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tada
authors.forename: Hakan
authors.initials: H
authors.lastname: Oral
authors.forename: Frank
authors.initials: F
authors.lastname: Pelosi
authors.forename: Bradley P
authors.initials: BP
authors.lastname: Knight
authors.forename: S Adam
authors.initials: SA
authors.lastname: Strickberger
authors.forename: Fred
authors.initials: F
authors.lastname: Morady
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000188:drug therapy* / Q000517:prevention & control; D016009:Chi-Square Distribution; D004554:Electric Countershock / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D013449:Sulfonamides / Q000627:therapeutic use*; D014700:Verapamil / Q000627:therapeutic use*
chemical_list: D013449:Sulfonamides; C067192:ibutilide; D014700:Verapamil