title: Cost-effectiveness of the implantable cardioverter defibrillator: a review of current evidence.
abstract: BACKGROUND
  Implantable cardioverter defibrillator (ICD) therapy is indicated for patients at risk for sudden cardiac death (SCD) due to ventricular tachycardia (VT) or ventricular fibrillation (VF). The high relative cost of therapy with the ICD versus antiarrhythmic drugs has raised questions regarding its cost-effectiveness. To address these questions, we review the literature on ICD cost-effectiveness.
  
  
  RESULTS
  MEDLINE and other databases were searched for articles published since 1980 reporting original data on the cost-effectiveness of ICD versus drug therapy for patients at risk for SCD. Data on costs and life-years were abstracted and studies grouped into decision analysis models and trial-based analyses. Cost-effectiveness ratios were inflated to 2002 US dollars. Thirteen economic studies were included in this review: 6 decision-analytic models, 4 economic analysis alongside randomized controlled trials, and 1 observational study. Two additional studies evaluated the cost-effectiveness of ICDs stratified by mortality risk. Studies varied in time horizon, and in all but one study ICD therapy was more costly than drug therapy. Early models assumed larger survival benefits than were observed in subsequent trials; therefore, ICDs appeared to be more cost-effective (i.e., US dollars 28000-US dollars 60000 per life-year gained). Three large clinical trial-based studies estimated that the cost per life-year gained was between US dollars 30181 and US dollars 185000. Stratified analyses show that patients at higher risk for mortality due to structural heart disease (e.g., left ventricular ejection fraction <35%) benefit more from ICD therapy, resulting in lower cost-effectiveness ratios.
  
  
  CONCLUSIONS
  ICD therapy continues to evolve with changing methods of implantation and improving technology. Current evidence suggests that ICDs may be a cost-effective option in patients at high risk for VT/VF. The cost-effectiveness of ICD therapy for primary and secondary prevention of SCD depends upon patient characteristics that influence their prior risk of mortality. Further research on patient selection criteria and the measurement of health-related quality of life is required.
authors.affiliation: Centre for Evaluation of Medicines, Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Larry D
authors.initials: LD
authors.lastname: Lynd
authors.forename: Bernie J
authors.initials: BJ
authors.lastname: O'Brien
mesh_terms: D001145:Arrhythmias, Cardiac / Q000150:complications / Q000191:economics* / Q000401:mortality / Q000628:therapy*; D002304:Cardiac Pacing, Artificial / Q000191:economics*; D002986:Clinical Trials as Topic; D017281:Cost of Illness; D003362:Cost-Benefit Analysis; D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000517:prevention & control*; D003661:Decision Support Techniques; D019317:Evidence-Based Medicine; D017048:Health Care Costs; D006801:Humans; D010138:Pacemaker, Artificial / Q000191:economics*; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology