title: Dronedarone for prevention of atrial fibrillation: a dose-ranging study.
abstract: OBJECTIVE
  Dronedarone, a benzofurane derivative without iodine substituents, shares the electrophysiologic properties of amiodarone. This study was designed to determine the most appropriate dose of dronedarone for prevention of atrial fibrillation (AF) after cardioversion.
  
  
  RESULTS
  Patients with persistent AF were randomly allocated to 800, 1200, 1600 mg daily doses of dronedarone or placebo. The main analysis was conducted on 199/270 patients, who entered the maintenance phase following pharmacological cardioversion or, if unsuccessful, DC cardioversion. Within 6-month follow-up, the time to AF relapse increased on dronedarone 800 mg, with a median of 60 days vs 5.3 days in the placebo group (relative risk reduction 55% [95% CI, 28 to 72%] P=0.001). No significant effect was seen at higher doses. Spontaneous conversion to sinus rhythm on dronedarone occurred in 5.8 to 14.8% of patients (P=0.026). There were no proarrhythmic reactions. Drug-induced QT prolongation was only noticed in the 1600 mg group. Premature drug discontinuations affected 22.6% of subjects given 1600 mg dronedarone versus 3.9% on 800 mg and were mainly due to gastrointestinal side effects. No evidence of thyroid, ocular or pulmonary toxicity was found.
  
  
  CONCLUSIONS
  Dronedarone, at a 800 mg daily dose, appears to be effective and safe for the prevention of AF relapses after cardioversion. The absence of thyroid side effects and of proarrhythmia are important features of the drug. Further studies are needed to better delineate the antiarrhythmic profile of the drug.
authors.affiliation: Division of Cardiology, Hôpital Cardiologique, Lyon, France.
authors.forename: Paul
authors.initials: P
authors.lastname: Touboul
authors.forename: Josep
authors.initials: J
authors.lastname: Brugada
authors.forename: Alessandro
authors.initials: A
authors.lastname: Capucci
authors.forename: Harry J G M
authors.initials: HJ
authors.lastname: Crijns
authors.forename: Nils
authors.initials: N
authors.lastname: Edvardsson
authors.forename: Stefan H
authors.initials: SH
authors.lastname: Hohnloser
mesh_terms: D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000493:pharmacokinetics; D001281:Atrial Fibrillation / Q000517:prevention & control*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D010393:Pempidine / Q000008:administration & dosage* / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D012008:Recurrence; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents; C017276:dropempine; D010393:Pempidine