title: Concurrent Cardioversion of Atrial Fibrillation during ICD Shock Testing.
abstract: BACKGROUND
  Many patients receiving an implantable cardioverter-defibrillator (ICD) also have atrial fibrillation (AF). Shock testing during ICD implantation carries a potential risk of cardioversion to sinus rhythm (SR) and thrombembolic events. We aimed to analyze the recurrence of AF after cardioversion to SR during ICD shock testing.
  
  
  METHODS
  A total of 555 consecutive patients referred to a tertiary hospital in Switzerland for ICD implantation or generator exchange between 02/2002 and 03/2010 were screened for AF. Fifty-seven patients who were in AF at the time of ICD shock testing were included.
  
  
  RESULTS
  Forty-four patients (77%) were successfully cardioverted from AF to SR. Type of AF (persistent, not permanent 64 vs 31% of cardioverted patients) was the only predictor. Thirty-nine patients (89%) experienced a recurrence of AF/atrial flutter after a median of 54 days (interquartile range 35-251 days). The only predictor for recurrence of AF was previous AF declared as permanent. No ischemic stroke occurred during hospitalization for the procedure.
  
  
  CONCLUSIONS
  For patients in AF undergoing shock testing at the time of ICD implant, there is a high chance of cardioversion from AF to SR, but there is also a high risk of early recurrence. Decisions regarding long-term anticoagulation should not be based on the heart rhythm immediately following shock testing.
authors: Division of Cardiology, University of Basel Hospital, Basel, Switzerland.
authors: Annina S
authors: AS
authors: Vischer
authors: Division of Cardiology, University of Basel Hospital, Basel, Switzerland.|Herzpraxis Aeschenvorstadt, Basel, Switzerland.
authors: Marcus
authors: M
authors: Mutschelknauss
authors: Division of Cardiology, University of Basel Hospital, Basel, Switzerland.
authors: Michael S
authors: MS
authors: Kühne
authors: Division of Cardiology, University of Basel Hospital, Basel, Switzerland.
authors: Stefan
authors: S
authors: Osswald
authors: Division of Cardiology, University of Basel Hospital, Basel, Switzerland.
authors: Christian
authors: C
authors: Sticherling
authors: Division of Cardiology, University of Basel Hospital, Basel, Switzerland.
authors: Beat A
authors: BA
authors: Schaer
mesh_terms: D001281:Atrial Fibrillation / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control*; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D019544:Equipment Failure Analysis; D005260:Female; D006333:Heart Failure / Q000150:complications* / Q000175:diagnosis / Q000517:prevention & control*; D006801:Humans; D008297:Male; D012008:Recurrence; D016896:Treatment Outcome
keywords: atrial fibrillation; cardioversion; implantable cardioverter-defibrillator; shock testing; sinus rhythm