title: Amiodarone after unsuccessful direct-current cardioversion of persistent atrial fibrillation.
abstract: OBJECTIVE
  To assess the safety and efficacy of amiodarone used after unsuccessful direct current (DC) cardioversion of persistent atrial fibrillation (AF).
  
  
  METHODS
  The study group comprised 67 patients (F/M 26/41; mean age 61.3+/-11.2 years) after unsuccessful DC cardioversion (DCC) of persistent AF (mean arrhythmia duration 212.6+/-135.2 days) in whom another attempt of DCC was intended. Repeat DC cardioversion was performed after loading with oral amiodarone, for a period necessary to achieve a cumulative dose of up to 12.0-16.0 g. Pretreatment was an outpatient procedure. After successful DC cardioversion all study subjects received a maintenance dose of amiodarone, 100-200 mg daily, aimed at preventing AF. The follow-up period was 12 months.
  
  
  RESULTS
  Spontaneous conversion to sinus rhythm (SR) during amiodarone pretreatment was observed in 13 pts (19.2%). DCC was performed in 54 pts and SR was restored in 41 of the study pts (76%). Complications occurred in 3 pts, including 1 case of apparent hyperthyroidism and 2 cases of decreased TSH level, and required amiodarone withdrawal. After 12 months, 72.2% of pts maintained SR on low dose (179.2+/-42.1 mg/day) amiodarone. Spontaneous conversion to SR during amiodarone loading was significantly related to long-term SR maintenance after successful DC cardioversion (p<0.013; RR 2.01; 95% CI 1.34-3.03).
  
  
  CONCLUSIONS
  Pretreatment with amiodarone and repeat DC cardioversion results in sinus rhythm restoration in about 80.6% of pts with persistent AF after an initial unsuccessful attempt. Direct-current cardioversion can be performed safely taking standard precautions for patients receiving amiodarone. At 12 months after successful repeated DC cardioversion, more than 72.2% of pts on low-dose amiodarone maintain SR.
authors.affiliation: I Katedra i Klinika Kardiologii, Akademia Medyczna, ul. Banacha 1 a, 02-097 Warszawa. dkosior@amwaw.edu.pl
authors.forename: Dariusz A
authors.initials: DA
authors.lastname: Kosior
authors.forename: Beata
authors.initials: B
authors.lastname: Wozakowska-Kapłon
authors.forename: Mariusz
authors.initials: M
authors.lastname: Jasik
authors.forename: Marek
authors.initials: M
authors.lastname: Kiliszek
authors.forename: Daniel
authors.initials: D
authors.lastname: Rabczenko
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Opolski
mesh_terms: D000638:Amiodarone / Q000008:administration & dosage / Q000627:therapeutic use*; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000188:drug therapy* / Q000209:etiology / Q000628:therapy; D003131:Combined Modality Therapy; D004554:Electric Countershock / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017211:Treatment Failure
chemical_list: D000889:Anti-Arrhythmia Agents; D000638:Amiodarone