title: Optimal timing of electrical cardioversion in patients with persistent atrial fibrillation.
abstract: BACKGROUND
  Many studies have tried to propose risk factors for atrial fibrillation recurrence after a successful pharmacological or electrical cardioversion. Regarding the duration of atrial fibrillation before electrical cardioversion, only limited data exist. The aim of our study was to investigate the effect of atrial fibrillation duration on long-term sinus rhythm maintenance in patients after successful electrical cardioversion of persistent atrial fibrillation.
  
  
  METHODS
  Three hundred one patients after successful electrical cardioversion were included in the analysis. The patients were followed for 2 years. Electrocardiogram showing atrial fibrillation was considered the study endpoint.
  
  
  RESULTS
  After mean observational time of 377±311 days, atrial fibrillation occurred in 168 patients (61.5%). Multivariate logistic regression analysis showed the duration of atrial fibrillation was the only predictor of atrial fibrillation recurrence (OR 1.06; CI 1.00-1.11; P=.036), while amiodarone appeared to protect against atrial fibrillation recurrence OR 0.26; CI 0.07-0.95; P=.041). A Cox proportional hazards multivariate model predicted atrial fibrillation recurrence rate of atrial fibrillation ≥10 months (OR 1.87, CI 1.26 to 2.76, P=.002) and treatment with amiodarone (OR 0.55, CI 0.40-0.76, P=.000).
  
  
  CONCLUSIONS
  Atrial fibrillation duration before electric cardioversion is a significant predictor of atrial fibrillation recurrence rate after successful restoration of sinus rhythm. Further studies are needed to clarify the implications of atrial fibrillation duration on sinus rhythm persistence after a successful cardioversion.
authors.affiliation: Department of Cardiology and Angiology, University Medical Centre, Maribor, Slovenia. franjo.naji@yahoo.com
authors.forename: Franjo
authors.initials: F
authors.lastname: Naji
authors.forename: Damijan
authors.initials: D
authors.lastname: Vokac
authors.forename: Vojko
authors.initials: V
authors.lastname: Kanic
authors.forename: Miso
authors.initials: M
authors.lastname: Sabovic
mesh_terms: D000368:Aged; D000638:Amiodarone / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000188:drug therapy / Q000503:physiopathology / Q000628:therapy*; D004554:Electric Countershock; D004562:Electrocardiography; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D055502:Secondary Prevention; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents; D000638:Amiodarone