title: Permanent pacemaker implantation after aortic valve replacement: Long-term dependency or rhythm recovery?
abstract: BACKGROUND
  Conduction disturbances requiring permanent pacemaker (PM) implantation occur in 3-12% of patients after aortic valve replacement (AVR). Our aim was to assess long-term PM dependency and its predictors in these patients.
  
  
  METHODS
  We conducted a retrospective study of all consecutive patients undergoing permanent PM implantation after AVR between January 2004 and December 2010. Absence of sinus rhythm or atrial fibrillation with appropriate ventricular response at a pacing rate of 30 bpm for 10 s was defined as pacemaker dependency.
  
  
  RESULTS
  Ninety-one patients underwent permanent PM implantation and during follow-up (1026.6 ± 732.0 days) 64% of them did not recover rhythm. Age, conduction disorders on the preoperative ECG, negative chronotropic medication before surgery, cardiopulmonary bypass and aortic cross-clamp times did not influence rhythm recovery. In multivariate analysis, valvular disease etiology related to endocarditis, prosthetic dysfunction and bicuspid valve were associated with long-term PM dependency (OR 5.05; CI: 1.43-17.75).
  
  
  CONCLUSIONS
  The majority of patients undergoing permanent PM implantation after AVR did not recover from conduction disorders during follow-up. The etiology of valvular disease was an independent predictor of late PM dependence.
authors: Department of Cardiology, São João Hospital, Porto, Portugal. Electronic address: ribeiro_vania@hotmail.com.
authors: Vânia
authors: V
authors: Ribeiro
authors: Department of Cardiology, São João Hospital, Porto, Portugal.
authors: Raquel
authors: R
authors: Mota Garcia
authors: Department of Cardiology, São João Hospital, Porto, Portugal.
authors: Cecília
authors: C
authors: Frutuoso
authors: Department of Cardiology, São João Hospital, Porto, Portugal.
authors: Filipa
authors: F
authors: Melão
authors: EPIUnit - Institute of Public Health of the University of Porto, Clinical Epidemiology, Predictive Medicine and Public Health Department, University of Porto Medical School, Porto, Portugal.
authors: Marta
authors: M
authors: Pereira
authors: Department of Cardiothoracic Surgery, São João Hospital, Porto, Portugal.
authors: Paulo
authors: P
authors: Pinho
authors: Department of Cardiology, São João Hospital, Porto, Portugal.
authors: Maria Júlia
authors: MJ
authors: Maciel
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000601:surgery*; D001145:Arrhythmias, Cardiac / Q000601:surgery*; D005260:Female; D006350:Heart Valve Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D011183:Postoperative Complications / Q000601:surgery*; D012189:Retrospective Studies; D013997:Time Factors
keywords: Aortic valve replacement; Conduction disorder; Distúrbios da condução; Pacemaker permanente; Permanent pacemaker; Substituição valvular aórtica