title: Primary ICD-therapy in patients with advanced heart failure: selection strategies and future trials.
abstract: BACKGROUND
  For allocation of primary ICD-therapy, a possible lower limit of inclusion criteria--defining overly advanced heart failure--is less well investigated. Also, a multi-variable approach to stratification beyond ejection fraction (LVEF) appears warranted. We examined whether adding a selection limit of peak VO(2) <or= 14 ml/kg/min to LVEF <or= 20% improves stratification. Furthermore, we sought to provide current survival data and a size-estimate for prospective trials based on real-life data for this high risk cohort.
  
  
  METHODS
  In our prospective clinical registry 1,926 patients with systolic CHF were recruited consecutively since 1994. Of these patients, 292 met the selection criteria described above. The mean age was 57.6 +/- 9.5 years, 83% were male, 37% had ischemic cardiomyopathy and 28% received primary ICD-therapy. All cause mortality was considered as end point.
  
  
  RESULTS
  Median follow-up was 45 (18-86) months. ICD was not a significant predictor of outcome either for the entire population, or grouped according to aetiology of CHF. Still, 3-year mortality was 15% (ICD-patients) Vs. 28% (non-ICD-patients); P = 0.05; under combination medical therapy. Inversely, in ICD-patients medical combination therapy conveyed a significant survival benefit (P < 0.001). Consequently, the number-needed-to-treat was eight under combination therapy and the size estimate amounts to 300 patients for a prospective trial in this cohort.
  
  
  CONCLUSIONS
  A cut-off of LVEF <or= 20% and pVO(2) <or= 14 ml/kg/min could identify patients that do not draw a significant survival benefit from adjunct primary ICD-therapy. Our results indicate the need for a specific randomized trial in this cohort. The according mortality data and a size estimate are provided.
authors.affiliation: Department of Cardiology, University of Heidelberg, Heidelberg, Germany. lutz_frankenstein@med.uni-heidelberg.de
authors.forename: Lutz
authors.initials: L
authors.lastname: Frankenstein
authors.forename: Christian
authors.initials: C
authors.lastname: Zugck
authors.forename: Manfred
authors.initials: M
authors.lastname: Nelles
authors.forename: Dieter
authors.initials: D
authors.lastname: Schellberg
authors.forename: Andrew
authors.initials: A
authors.lastname: Remppis
authors.forename: Hugo
authors.initials: H
authors.lastname: Katus
mesh_terms: D015897:Comorbidity; D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006333:Heart Failure / Q000401:mortality* / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D015995:Prevalence; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000401:mortality* / Q000517:prevention & control*