title: A randomized comparison of defibrillation thresholds in the right ventricular outflow tract versus right ventricular apex.
abstract: OBJECTIVE
  To determine whether the placement of an implantable cardioverter-defibrillator (ICD) lead in the right ventricular outflow tract (RVOT) has the same defibrillation threshold (DFT) as the right ventricular apex (RVA).
  
  
  BACKGROUND
  Right ventricular ICD leads have usually been placed in the RVA. Development of active fixation technology has allowed the placement of these leads in alternate locations such as the RVOT.
  
  
  METHODS
  At time of device implantation, 26 patients with either ischemic or dilated cardiomyopathy underwent DFT testing in both the RVA and RVOT using a binary search algorithm.
  
  
  RESULTS
  Placement of the lead in the RVA had a mean DFT of 7.6 +/- 2.8 J while the placement of the lead in the RVOT had a mean DFT of 10.3 +/- 3.0 J. The median (25th and 75th percentiles) DFTs in the RVA and RVOT were 7.5 J (6 and 11 J) and 11 J (9 and 14 J), respectively (p = 0.0002).
  
  
  CONCLUSIONS
  Placement of the right ventricular lead in the RVA has a significantly lower DFT than placement of the lead in the RVOT.
authors.affiliation: St. Mary's/Duluth Clinic, Duluth, MN 55805, USA. mike@mollerus.org
authors.forename: Michael
authors.initials: M
authors.lastname: Mollerus
authors.forename: Margaret
authors.initials: M
authors.lastname: Lipinski
authors.forename: Thomas
authors.initials: T
authors.lastname: Munger
mesh_terms: D017147:Defibrillators, Implantable; D004056:Differential Threshold; D004554:Electric Countershock / Q000379:methods*; D005260:Female; D006333:Heart Failure / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome; D014694:Ventricular Outflow Obstruction / Q000517:prevention & control*