title: Comparison of outcomes in patients undergoing defibrillation threshold testing at the time of implantable cardioverter-defibrillator implantation versus no defibrillation threshold testing.
abstract: BACKGROUND
  Inability to perform defibrillation threshold (DFT) testing during implantable cardioverter defibrillator (ICD) implantation due to co-morbidities may influence long-term survival.
  
  
  METHODS
  Retrospective review at The University of Michigan (1999-2004) identified 55 patients undergoing ICD implantation without DFT testing ("No-DFT group"). A randomly selected sample of patients (n = 57) undergoing standard DFT testing ("DFT group") was compared in terms of appropriate shocks, clinical shock efficacy and all-cause mortality.
  
  
  RESULTS
  DFT testing was withheld due to hypotension, atrial fibrillation with inability to exclude left atrial thrombus, left ventricular thrombus, CHF and/or ischemia. The No-DFT group had a similar appropriate shock rate, but lower total survival (69.1% vs. 91.2%, p = 0.004) than the DFT group. The No-DFT group had a higher incidence of ventricular fibrillation (VF) episodes (9.1% vs. 3.1%, p = 0.037), and deaths attributable to VF (3 of 17 deaths vs. 0 of 5 deaths) compared to the DFT group. Multivariate analysis found a trend toward increased risk of death in the No-DFT group (HR 3.18, 95% CI 0.82-12.41, p = 0.095) after adjusting for baseline differences in gender distribution, NYHA class and prior CABG.
  
  
  CONCLUSIONS
  In summary, overall mortality was higher in the No-DFT group. More deaths attributable to VF occurred in the No-DFT group. Thus, DFT testing should therefore remain the standard of care. Nevertheless, ICD therapy should not be withheld in patients who meet appropriate implant criteria simply on the basis of clinical scenarios that preclude routine DFT testing. (Cardiol J 2007; 14: 463-469).
authors.forename: Burr
authors.initials: B
authors.lastname: Hall
authors.forename: Vinodh
authors.initials: V
authors.lastname: Jeevanantham
authors.forename: Ethan
authors.initials: E
authors.lastname: Levine
authors.forename: James
authors.initials: J
authors.lastname: Daubert
authors.forename: Scott
authors.initials: S
authors.lastname: McNitt
authors.forename: Freburr
authors.initials: F
authors.lastname: Hall
authors.forename: Vinodh
authors.initials: V
authors.lastname: Jeevanantham
authors.forename: Ethan
authors.initials: E
authors.lastname: Levine
authors.forename: James
authors.initials: J
authors.lastname: Daubert
authors.forename: Scott
authors.initials: S
authors.lastname: McNitt
authors.forename: Fred Morady And Frank Pelosiburr
authors.initials: FM
authors.lastname: Hall
authors.forename: Vinodh
authors.initials: V
authors.lastname: Jeevanantham
authors.forename: Ethan
authors.initials: E
authors.lastname: Levine
authors.forename: James
authors.initials: J
authors.lastname: Daubert
authors.forename: Scott
authors.initials: S
authors.lastname: McNitt
authors.forename: Fred Morady And Frank Pelosid
authors.initials: FM
authors.lastname: Morady
authors.forename: Frank
authors.initials: F
authors.lastname: Pelosi