title: Electrical cardioversion of persistent atrial fibrillation: acute and long-term results stratified according to arrhythmia duration.
abstract: BACKGROUND
  Current definition of persistent atrial fibrillation (PAF) enrolls a heterogeneous population with different atrial fibrillation (AF) exposure and degree of atrial substrate. Study aims were to evaluate acute and long-term results of electrical cardioversion (ECV) and to identify temporal cutoff of previous AF exposure to reclassify PAF in subgroups with different chance of sinus rhythm (SR) maintenance.
  
  
  METHODS
  Five hundred twenty-one patients (66% men; age 69 ± 10 years) with PAF undergoing ECV, were divided in four groups according to AF duration at the time of ECV: group A with AF ≤2 months (141 patients); group B with AF >2 and ≤4 months (176 patients); group C with AF >4 and ≤6 months (89 patients); and group D with AF >6 months and <1 year (115 patients).
  
  
  RESULTS
  There was no difference in term of acute success among groups (98.5% vs 97.1% vs 98.9% vs 96.5%, respectively, P = 0.95). At 5-year follow-up, 198 (41%) patients were in SR: 50% in group A, 44% in group B, 42% in group C, and 25% in group D (P < 0.001). At the multivariate analysis, previous ECV (hazard ratio [HR] 1.55, P < 0.001), left atrium enlargement (HR 1.39, P = 0.013), and AF duration >6 months at time of procedure (HR 1.59, P = 0.001) independently predict ECV failure.
  
  
  CONCLUSIONS
  ECV is associated with high acute success rate and low complications rate. Long-term results are strongly related with AF duration at time of ECV: a cutoff of >6 months helps in selecting patients that can take greater advantage of the procedure.
authors: Cardiology Division, Department of Internal Medicine, San Giovanni Battista Hospital, University of Turin, Italy. elisabetta.toso@libero.it
authors: Elisabetta
authors: E
authors: Toso
authors: Alessandro
authors: A
authors: Blandino
authors: Davide
authors: D
authors: Sardi
authors: Alberto
authors: A
authors: Battaglia
authors: Lucia
authors: L
authors: Garberoglio
authors: Salvatore
authors: S
authors: Miceli
authors: Giuseppe
authors: G
authors: Azzaro
authors: Attilio Luca
authors: AL
authors: Capello
authors: Fiorenzo
authors: F
authors: Gaita
mesh_terms: D000208:Acute Disease; D000368:Aged; D001281:Atrial Fibrillation / Q000401:mortality* / Q000517:prevention & control*; D002908:Chronic Disease; D018572:Disease-Free Survival; D004554:Electric Countershock / Q000401:mortality*; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D013534:Survival; D016019:Survival Analysis; D016896:Treatment Outcome