title: Characterization and financial impact of implantable cardioverter-defibrillator patients without interventions 5 years after implantation.
abstract: BACKGROUND
  Implantable cardioverter defibrillators (ICD's) are increasingly used for primary and secondary prevention of sudden cardiac death. However, data on how many ICD patients indeed receive appropriate ICD therapy during long-term follow-up is scarce.
  
  
  OBJECTIVE
  The aim of our study was to determine the number of patients without appropriate ICD therapy 5 years after ICD implantation, to identify predicting factors, to assess the occurrence of late first ICD therapy and to quantify the financial impact of ICD therapy in a real-world setting.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  We prospectively enrolled 322 consecutive ICD patients. Baseline data were collected at implantation and patients were followed for a median of 7.3 years (IQR 5.8-9.2 years). Time to first appropriate ICD therapy (either antitachycardia pacing or cardioversion) was documented.
  
  
  RESULTS
  Five years after implantation, 139 patients (43%) had not received appropriate ICD therapy. In multivariable analysis, a primary prevention indication and negative electrophysiological studies prior to ICD implantation were independent predictors of freedom from ICD therapy. Of the patients without ICD therapy, 5 years after implantation, 25% had experienced inappropriate ICD shocks. Two hundred and seven devices (1.5 devices per patient) were needed for the 139 patients without ICD intervention within 5 years, accounting for € 31,784 per patient. During an additional follow-up of 3 years, 12% of the patients with unused ICD received a late first appropriate ICD therapy.
  
  
  CONCLUSIONS
  About half of the ICD patients receive appropriate ICD therapy within 5 years after implantation. Furthermore, there is a significant proportion of patients receiving late first shocks after five initially uneventful years.
authors.affiliation: Department of Internal Medicine, Division of Cardiology, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland. treichlin@uhbs.ch
authors.forename: T
authors.initials: T
authors.lastname: Reichlin
authors.forename: M
authors.initials: M
authors.lastname: Kühne
authors.forename: C
authors.initials: C
authors.lastname: Sticherling
authors.forename: S
authors.initials: S
authors.lastname: Osswald
authors.forename: B
authors.initials: B
authors.lastname: Schaer
mesh_terms: D000368:Aged; D016757:Death, Sudden, Cardiac / Q000517:prevention & control; D017147:Defibrillators, Implantable / Q000009:adverse effects / Q000191:economics / Q000592:standards*; D004554:Electric Countershock / Q000009:adverse effects / Q000191:economics / Q000706:statistics & numerical data*; D004812:Epidemiologic Methods; D005260:Female; D017048:Health Care Costs / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011184:Postoperative Period; D011379:Prognosis; D011475:Prosthesis Failure; D012086:Reoperation; D013557:Switzerland; D019564:Unnecessary Procedures / Q000706:statistics & numerical data