title: Can we predict the failure of electrical cardioversion of acute atrial fibrillation? The FinCV study.
abstract: BACKGROUND
  Data on predictors of failure of electrical cardioversion of acute atrial fibrillation are scarce.
  
  
  METHODS
  We explored 6,906 electrical cardioversions of acute (<48 hours) atrial fibrillation in 2,868 patients in a retrospective multicenter study.
  
  
  RESULTS
  The success rate of electrical cardioversion was 94.2%. In 26% of unsuccessful cardioversions, the cardioversion was performed successfully later. Antiarrhythmic drug therapy, short (<12 hours) duration of atrial fibrillation episode, advanced age, permanent pacemaker, history of atrial fibrillation episodes within 30 days before cardioversion, and β-blockers were independent predictors of unsuccessful electrical cardioversion. In the subgroup of patients with cardioversion of the first atrial fibrillation episode (N = 1,411), the short duration of episode (odds ratio [OR] = 2.28; 95% confidence interval [CI] 1.34-3.90, P = 0.003) and advanced age (OR = 1.03; 95% CI 1.02-1.05, P < 0.001) were the only independent predictors of unsuccessful cardioversion. After successful cardioversion, the rate of early (<30 days) clinical recurrence of atrial fibrillation was 17.3%. The index cardioversion being performed due to the first atrial fibrillation episode was the only predictor of remaining in the sinus rhythm.
  
  
  CONCLUSIONS
  A short (<12 hours) duration of acute atrial fibrillation is a significant predictor of unsuccessful cardioversion, especially during the first attack. First atrial fibrillation episode was the only predictor of remaining in the sinus rhythm.
authors.affiliation: Heart Center, Turku University Hospital and University of Turku, Turku, Finland.
authors.forename: Toni
authors.initials: T
authors.lastname: Grönberg
authors.forename: Juha E K
authors.initials: JE
authors.lastname: Hartikainen
authors.forename: Ilpo
authors.initials: I
authors.lastname: Nuotio
authors.forename: Fausto
authors.initials: F
authors.lastname: Biancari
authors.forename: Tuija
authors.initials: T
authors.lastname: Vasankari
authors.forename: Marko
authors.initials: M
authors.lastname: Nikkinen
authors.forename: Antti
authors.initials: A
authors.lastname: Ylitalo
authors.forename: K E Juhani
authors.initials: KE
authors.lastname: Airaksinen
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000453:epidemiology / Q000628:therapy*; D002304:Cardiac Pacing, Artificial; D004554:Electric Countershock; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012008:Recurrence; D012189:Retrospective Studies; D017211:Treatment Failure
keywords: antiarrhythmic drug therapy; atrial fibrillation; cardioversion; clinical recurrence; failure rate