Clinical and economic implications of the Multicenter Automatic Defibrillator Implantation Trial-II.

BACKGROUND

The Multicenter Automatic Defibrillator Implantation Trial (MADIT)-II demonstrated that implantable cardioverter defibrillators (ICDs) save lives when used in patients with a history of myocardial infarction (MI) and an ejection fraction of 0.3 or less.

OBJECTIVE

To investigate the cost-effectiveness of implanting ICDs in patients who met MADIT-II eligibility criteria and were enrolled in the Duke Cardiovascular Database between 1 January 1986 and 31 December 2001.

DESIGN

Cost-effectiveness analysis.

DATA SOURCES

Published literature, databases owned by Duke University Medical Center, and Medicare data.

TARGET POPULATION

Adults with a history of MI and an ejection fraction of 0.3 or less.

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTIONS

ICD therapy versus conventional medical therapy.

OUTCOMES MEASURES

Cost per life-year gained and incremental cost-effectiveness.

RESULTS

Compared with conventional medical therapy, ICDs are projected to result in an increase of 1.80 discounted years in life expectancy and an incremental cost-effectiveness ratio of 50,500 dollars per life-year gained. Cost-effectiveness varied dramatically with changes in time horizon: The cost-effectiveness ratio increased to 67,800 dollars per life-year gained, 79,900 dollars per life-year gained, 100,000 dollars per life-year gained, 167,900 dollars per life-year gained, and 367,200 dollars per life-year gained for 15-year, 12-year, 9-year, 6-year, and 3-year time horizons, respectively. Changing the frequency of follow-up visits, complication rates, and battery replacements had less of an effect on the cost-effectiveness ratios than reducing the cost of ICD placement and leads.

LIMITATIONS

The study was limited by the completeness of the data, referral bias, difference in medical therapy between the Duke cohort and the MADIT-II cohort, and not addressing potential upgrades to biventricular devices.

CONCLUSIONS

The economic expense of defibrillator implantation in all patients who meet MADIT-II eligibility criteria is substantial. However, in the range of survival benefit observed in MADIT-II, ICD therapy for these patients is economically attractive by conventional standards.