title: Severe left ventricular systolic dysfunction increases atrial fibrillation after ablation of atrial flutter.
abstract: BACKGROUND
  Atrial fibrillation (Afib) that occurs after a successful atrial flutter (AFL) ablation may negate the potential benefits of the ablation. Afib occurs more often when severe left ventricular systolic dysfunction (LVSD) is present. We hypothesized that even after a successful AFL ablation, the incidence of postablation Afib is increased when severe LVSD is present.
  
  
  METHODS
  Ninety consecutive patients with LVSD who underwent ablation for AFL at Montefiore Medical Center from August 2001 to January 2005 were classified according to the severity of LVSD. Group 1 (n = 36) consisted of patients with EF < or = 35%, and group 2 (n = 54) consisted of patients with EF 36-55%. There were no statistically significant differences in baseline patient characteristics between the two groups.
  
  
  RESULTS
  During a mean follow up of 350 days, Afib occurred in 31% (n = 11; 8 with prior history of AFib) in group 1, and 7.4% (n = 4; all with prior history of Afib) in group 2. Cumulative probability of remaining Afib-free in group 1 versus group 2 was 75% versus 96% at 365 days, and 69% versus 91% at 600 days (P = 0.01). A prior history of Afib did not interact with EF when analyzed with a logistic regression analysis.
  
  
  CONCLUSIONS
  After an AFL ablation, the incidence of Afib is increased, and the probability of remaining free of Afib is decreased, when severe LVSD is present, independent of a prior history of Afib. This finding may have implications for optimal patient selection for AFL ablation, and the use of adjunctive therapies.
authors.affiliation: Arrhythmia Service of the Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, New York, USA.
authors.forename: Peter E
authors.initials: PE
authors.lastname: Zambito
authors.forename: Ashok
authors.initials: A
authors.lastname: Talreja
authors.forename: Susheel
authors.initials: S
authors.lastname: Gundewar
authors.forename: John
authors.initials: J
authors.lastname: Fisher
authors.forename: Kevin
authors.initials: K
authors.lastname: Ferrick
authors.forename: Jay
authors.initials: J
authors.lastname: Gross
authors.forename: Soo
authors.initials: S
authors.lastname: Kim
authors.forename: Eugen C
authors.initials: EC
authors.lastname: Palma
mesh_terms: D001281:Atrial Fibrillation / Q000453:epidemiology* / Q000209:etiology*; D001282:Atrial Flutter / Q000150:complications* / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D012189:Retrospective Studies; D012720:Severity of Illness Index; D018487:Ventricular Dysfunction, Left / Q000150:complications*