title: A comparison of right ventricular non-apical defibrillator lead position with traditional right ventricular apical position: a single centre experience.
abstract: BACKGROUND
  Implantable cardioverter defibrillator (ICD) leads have traditionally been placed at the right ventricular apex (RVA). An important minority of patients with an ICD may develop a future requirement for bradycardia support. Pacing from the RVA may be detrimental, promoting heart failure and mortality. Increasingly non-apical right ventricular (RVNA) lead positions have been suggested as an alternative pacing site.
  
  
  METHODS
  A retrospective review of 512 patients who received an ICD at our institution between 1999 and 2011 was conducted. A comparison of lead performance characteristics was performed between RVNA sites and those at RVA. Data were collated from chart review and the pacing database.
  
  
  RESULTS
  The mean follow-up period in the RVNA cohort was 40.4±25.9 months and in the RVA cohort it was 38±31.8 months (p=0.43). The RVNA cohort consisted of 144 leads and 368 leads in the RVA cohort. The groups had similar baseline clinical characteristics. No significant difference was detected in the proportion of patients receiving an appropriate ICD defibrillation (RVNA 10.4% vs. RVA 16.8%; p=0.07), inappropriate defibrillation (RVNA 7.6% vs. RVA 7.6%; p=0.99) or an unsuccessful defibrillation (RVNA 0% vs. RVA 1.7%; p=0.12). There was also no significant difference in the proportion of patients receiving successful anti-tachycardia pacing (ATP) (RVNA 13.2% vs. RVA 17.4%; p=0.49) or failed ATP (RVNA 2.7% vs. RVA 4.1%; p=0.25). There was no significant difference in lead impedance (p=0.99), sensing (p=0.59) and pacing threshold (p=0.34).
  
  
  CONCLUSIONS
  In this large retrospective study, RVNA ICD lead had similar stability and therapy efficacy compared to the traditional RVA position. This potentially has important implications for the suitability of RVNA as an alternative site for ICD leads.
authors.affiliation: University of Queensland, Brisbane, Queensland, Australia 4102. Electronic address: gerald.kaye@health.qld.gov.au.
authors.forename: Gerald C
authors.initials: GC
authors.lastname: Kaye
authors.affiliation: Department of Cardiology, Princess Alexandra Hospital, Ipswich Road, Wolloongabba, Brisbane, Queensland, Australia 4102.
authors.forename: Lim K
authors.initials: LK
authors.lastname: Eng
authors.affiliation: Department of Cardiology, Princess Alexandra Hospital, Ipswich Road, Wolloongabba, Brisbane, Queensland, Australia 4102.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Hunt
authors.affiliation: Department of Cardiology, Princess Alexandra Hospital, Ipswich Road, Wolloongabba, Brisbane, Queensland, Australia 4102.
authors.forename: Kieran M
authors.initials: KM
authors.lastname: Dauber
authors.affiliation: Department of Cardiology, Princess Alexandra Hospital, Ipswich Road, Wolloongabba, Brisbane, Queensland, Australia 4102.
authors.forename: John
authors.initials: J
authors.lastname: Hill
authors.affiliation: University of Queensland, Brisbane, Queensland, Australia 4102.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Gould
mesh_terms: D000368:Aged; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000009:adverse effects / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
keywords: Anti-tachycardia pacing; Defibrillation; Implantable cardioverter defibrillator; Right ventricular non-apical pacing; Right ventricular pacing