title: Right ventricular pacing is associated with impaired overall survival, but not with an increased incidence of ventricular tachyarrhythmias in routine cardioverter/defibrillator recipients with reservedly programmed pacing.
abstract: OBJECTIVE
  Data from previous defibrillator studies raised concern about right ventricular pacing (RVP) promoting heart failure progression and mortality in implantable cardioverter/defibrillator (ICD) patients. The present observational study re-examined the association of RVP, survival, and ventricular tachyarrhythmias/ventricular fibrillation (VT/VF) in routine ICD patients with restrictively programmed pacing.
  
  
  RESULTS
  In 213 ICD patients [183 men, left ventricular ejection fraction (LVEF) 37 +/- 15%, follow-up 37 +/- 18 months, no advanced atrioventricular (AV) block], the RVP proportion, survival, and the time to a first appropriate VT/VF episode were assessed. Electrograms were validated and the overall survival was determined. The RVP prevalence was dichotomized at > or = 30% (high RVP) vs. <30% (low RVP). High RVP (RVP 94%, n = 24) and low RVP (RVP 0%, n = 189) patients had similar LVEF, underlying heart disease, ICD indication, and medication. Multivariate Cox regression showed no difference in survival without appropriate VT/VF treatment [odds ratio (OR): 0.92, 95% confidence interval (CI): 0.41-2.04, P = 0.83]. Overall survival was significantly more favourable in low RVP patients (OR: 0.34, CI: 0.13-0.91, P = 0.03).
  
  
  CONCLUSIONS
  Frequent RVP is associated with impaired survival in ICD patients despite conservative pacing settings. Implantable cardioverter/defibrillator patients requiring concomitant bradycardia pacing should be cared for with particular attention to clinical worsening. Right ventricular pacing prevention and alternative modalities of ventricular pacing need prospective evaluation.
authors.affiliation: Charité-Universitaetsmedizin Berlin, Campus Virchow-Klinikum, Medizinische Klinik mit Schwerpunkt Kardiologie, Augustenburger Platz 1 13353, Berlin, Germany. martin.stockburger@charite.de
authors.forename: Martin
authors.initials: M
authors.lastname: Stockburger
authors.forename: Oezlem
authors.initials: O
authors.lastname: Celebi
authors.forename: Alice
authors.initials: A
authors.lastname: Krebs
authors.forename: Thomas
authors.initials: T
authors.lastname: Knaus
authors.forename: Aischa
authors.initials: A
authors.lastname: Nitardy
authors.forename: Dirk
authors.initials: D
authors.lastname: Habedank
authors.forename: Rainer
authors.initials: R
authors.lastname: Dietz
mesh_terms: D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D004554:Electric Countershock / Q000401:mortality*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006333:Heart Failure / Q000401:mortality* / Q000517:prevention & control*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D017180:Tachycardia, Ventricular; D016896:Treatment Outcome; D018497:Ventricular Dysfunction, Right / Q000401:mortality* / Q000517:prevention & control*