title: Critical analysis of ineffective post implantation implantable cardioverter-defibrillator-testing.
abstract: OBJECTIVE
  To test of the implantable-cardioverter-defibrillator is done at the time of implantation. We investigate if any testing should be performed.
  
  
  METHODS
  All consecutive patients between January 2006 and December 2008 undergoing implantable cardioverter-defibrillator (ICD) implantation/replacement (a total of 634 patients) were included in the retrospective study.
  
  
  RESULTS
  Sixteen patients (2.5%) were not tested (9 with LA/LV-thrombus, 7 due to operator's decision). Analyzed were 618 patients [76% men, 66.4 + 11 years, 24% secondary prevention (SP), 46% with left ventricular ejection fraction (LVEF) < 20%, 56% had coronary artery disease (CAD)] undergoing defibrillation safety testing (SMT) with an energy of 21 + 2.3 J. In 22/618 patients (3.6%) induced ventricular fibrillation (VF) could not be terminated with maximum energy of the ICD. Six of those (27%) had successful SMT after system modification or shock lead repositioning, 14 patients (64%) received a subcutaneous electrode array. Younger age (P= 0.0003), non-CAD (P= 0.007) and VF as index event for SP (P= 0.05) were associated with a higher incidence of ineffective SMT. LVEF < 20% and incomplete revascularisation in patients with CAD had no impact on SMT.
  
  
  CONCLUSIONS
  Defibrillation testing is well-tolerated. An ineffective SMT occurred in 4% and two third of those needed implantation of a subcutaneous electrode array to pass a SMT > 10 J.
authors.affiliation: Markus Roos, Heart Center, Salzburger Leite, 97616 Bad Neustadt a.d. Saale, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Roos
authors.affiliation: Markus Roos, Heart Center, Salzburger Leite, 97616 Bad Neustadt a.d. Saale, Germany.
authors.forename: J Christoph
authors.initials: JC
authors.lastname: Geller
authors.affiliation: Markus Roos, Heart Center, Salzburger Leite, 97616 Bad Neustadt a.d. Saale, Germany.
authors.forename: Marc-Alexander
authors.initials: MA
authors.lastname: Ohlow
keywords: Defibrillation test; Implantable cardioverter defibrillator; Implantable cardioverter-defibrillator; Safety margin test; Subcutaneous electrode array; Sudden cardiac death; Ventricular fibrillation