title: Risk of thromboembolic complications in patients with permanent atrial fibrillation undergoing cardioverter-defibrillator implantation.
abstract: BACKGROUND
  Cardioversion of atrial fibrillation (AF) carries the risk of thromboembolic complications and, therefore, anticoagulation therapy is routinely administered before and after this procedure. In patients with permanent AF who undergo implantation of cardioverter-defibrillator (ICD), anticoagulants are usually withdrawn during the perioperative period. However, in some patients sinus rhythm may be restored during defibrillation threshold (DFT) testing which potentially may increase the risk of thromboembolic complications.
  
  
  OBJECTIVE
  To assess the frequency of sinus rhythm restoration during ICD implantation in patients with permanent AF and the rate of both thromboembolic events and local bleeding complications which may occur due to temporary withdrawal of anticoagulation therapy and its re-initiation early after the procedure.
  
  
  METHODS
  Permanent AF was present in 23 (12%) of 193 patients selected for ICD implantation. All patients received prolonged oral anticoagulation according to the generally accepted standards. Anticoagulation therapy was stopped few days before the procedure and replaced by low molecular weight heparin which was administered up to 24 hours before ICD implantation and re-initiated 12-24 hours afterwards.
  
  
  RESULTS
  During DFT testing sinus rhythm was restored in 5 (21.7%) patients with AF. Clinical and DFT characteristics were similar in those who were converted to sinus rhythm and those who remained in AF. No thromboembolic events were noted in either group. Local haematoma at the site of ICD implantation occurred in two (8%) patients.
  
  
  CONCLUSIONS
  Sinus rhythm was restored in 21.7% of patients with permanent AF who underwent ICD implantation. Temporary withdrawal of anticoagulation therapy did not increase the risk of thromboembolic complications, however, its early re-initiation after implantation resulted in an increase in local bleeding complication rate.
authors.affiliation: Department of Coronary Artery Disease, National Institute of Cardiology, Warsaw, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Przybylski
authors.forename: Maciej
authors.initials: M
authors.lastname: Sterliński
authors.forename: Michał
authors.initials: M
authors.lastname: Lewandowski
authors.forename: Marek
authors.initials: M
authors.lastname: Srzednicki
authors.forename: Piotr
authors.initials: P
authors.lastname: Wolski
authors.forename: Aleksander
authors.initials: A
authors.lastname: Maciag
authors.forename: Mariusz
authors.initials: M
authors.lastname: Pytkowski
authors.forename: Ilona
authors.initials: I
authors.lastname: Kowalik
authors.forename: Hanna
authors.initials: H
authors.lastname: Szwed