title: Acute pericardial effusion following atrial fibrillation ablation: characteristics and relationship with arrhythmia recurrences.
abstract: BACKGROUND
  Pericardial effusion (PE) can occur during or after atrial fibrillation (AF) ablation, and may induce atrial arrhythmia.
  
  
  OBJECTIVE
  To characterize the impact of PE on arrhythmia recurrences following AF ablation.
  
  
  METHODS
  Patients referred for a first radiofrequency AF ablation were studied prospectively. Transthoracic echocardiography was performed before and 24h after the procedure. If PE was present, transthoracic echocardiography was repeated at 1 month to evaluate PE evolution. Early arrhythmia recurrences (EARs) were defined as any arrhythmia documented within 1 month of the procedure.
  
  
  RESULTS
  PE was diagnosed in 18/81 patients (22%); and was present in significantly more patients with persistent versus paroxysmal AF (14/40 [35%] vs 4/41 [10%]; P=0.008). PEs were mild (mean 6 ± 3mm), mainly asymptomatic (89%), and none required pericardiocentesis. Early and late arrhythmia recurrences were present in 25/81 (31%) and 29/81 (36%), respectively. The incidence of PE was significantly higher among patients with EARs versus those without (12/25 [48%] vs 6/56 [11%]; P=0.0004). By multivariable analysis, PE and duration in AF were the two independent predictors of EARs. PE incidence was similar in patients with and without late arrhythmia recurrences. At 1 month, no patients had PE on transthoracic echocardiography.
  
  
  CONCLUSIONS
  PE following radiofrequency AF ablation is frequent, particularly following persistent AF ablation. This effusion is generally mild, mainly asymptomatic, and independently associated with EARs.
authors.affiliation: hôpital Henri-Mondor, fédération de cardiologie, Creteil, France. nicolellouche@yahoo.com
authors.forename: Nicolas
authors.initials: N
authors.lastname: Lellouche
authors.forename: Frederic A
authors.initials: FA
authors.lastname: Sebag
authors.forename: Nathalie
authors.initials: N
authors.lastname: Elbaz
authors.forename: Majed
authors.initials: M
authors.lastname: Hassine
authors.forename: Najia
authors.initials: N
authors.lastname: Chaachoui
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Teiger
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Dubois-Randé
authors.forename: Pascal
authors.initials: P
authors.lastname: Lim
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects*; D016009:Chi-Square Distribution; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D005602:France; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010490:Pericardial Effusion / Q000175:diagnosis / Q000209:etiology*; D011446:Prospective Studies; D012008:Recurrence; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome