title: Right ventricular pacing can induce ventricular dyssynchrony in patients with atrial fibrillation after atrioventricular node ablation.
abstract: OBJECTIVE
  This study was designed to assess the effects of long-term right ventricular (RV) pacing on left ventricular (LV) dyssynchrony, LV function, and heart failure symptoms.
  
  
  BACKGROUND
  Atrioventricular (AV) node ablation and subsequent long-term RV pacing is a well-established treatment option in patients with atrial fibrillation (AF).
  
  
  METHODS
  In 55 patients with drug-refractory AF, AV node ablation and implantation of a pacemaker was performed. At baseline and after a mean of 3.8 +/- 1.7 years, LV dyssynchrony (by M-mode echocardiography and tissue Doppler imaging), LV function, and volumes and functional status were assessed.
  
  
  RESULTS
  After long-term RV pacing, 27 patients (49%) had developed LV dyssynchrony. Concomitantly, these patients worsened in heart failure symptoms (New York Heart Association functional class increased from 1.8 +/- 0.6 to 2.2 +/- 0.7, p < 0.05), with a decrease in LV ejection fraction (from 48 +/- 7% to 43 +/- 7%, p < 0.05) and an increase in LV end-diastolic volume (from 116 +/- 39 ml to 130 +/- 52 ml, p < 0.05). Conversely, patients without LV dyssynchrony did not deteriorate in heart failure symptoms, LV function, or LV volumes.
  
  
  CONCLUSIONS
  Long-term RV pacing can induce LV dyssynchrony in almost 50% of patients treated with AV node ablation for chronic AF. The development of LV dyssynchrony was associated with deterioration in heart failure symptoms, systolic LV function, and LV dilatation.
authors.affiliation: Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Laurens F
authors.initials: LF
authors.lastname: Tops
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Schalij
authors.forename: Eduard R
authors.initials: ER
authors.lastname: Holman
authors.forename: Lieselot
authors.initials: L
authors.lastname: van Erven
authors.forename: Ernst E
authors.initials: EE
authors.lastname: van der Wall
authors.forename: Jeroen J
authors.initials: JJ
authors.lastname: Bax
mesh_terms: D001281:Atrial Fibrillation / Q000628:therapy*; D001283:Atrioventricular Node / Q000601:surgery*; D002303:Cardiac Output, Low / Q000209:etiology / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects* / Q000379:methods*; D017115:Catheter Ablation; D004452:Echocardiography; D006352:Heart Ventricles; D006801:Humans; D012189:Retrospective Studies; D013997:Time Factors; D018754:Ventricular Dysfunction / Q000000981:diagnostic imaging / Q000209:etiology*