Clinical Question: Is an early invasive strategy (routine catheterization/revascularization) cost-effective in the treatment of unstable angina and non–ST-segment elevation myocardial infarction (MI)?

Setting: Inpatient (any location) with outpatient follow-up

Study Design: Randomized controlled trial (single-blinded)

Synopsis: Published clinical trials show that an early invasive strategy for unstable angina and non–ST-segment elevation MI is superior to a more conservative approach in reducing major cardiac events at six months. Mahoney and colleagues now present data examining total six-month costs and long-term cost-effectiveness of these two strategies. All patients in this trial were treated with aspirin, heparin, and tirofiban (a glycoprotein IIb/IIIa inhibitor). Subjects were randomized to an early invasive strategy that included catheterization within four to 48 hours and revascularization as appropriate, or to a conservative strategy that included catheterization only because of recurrent ischemia or a positive stress test. Inpatient and emergency department charges, as well as outpatient charges, were obtained from Medicare billing data. Drug costs were obtained from the Red Book of average wholesale prices. Although the initial hospitalization costs were higher for patients in the invasive strategy group, these costs were offset significantly at the six-month follow-up. The average total costs at six months were nearly equivalent for the invasive and conservative strategies ($21,813 and $21,277, respectively). The estimated cost per year of life gained for the invasive strategy ranged from $8,371 to $25,769, based on model assumptions. These costs are well within the range of what is considered to be cost-effective.

Bottom Line: In patients with unstable angina without ST-segment elevation treated with aspirin, heparin, and tirofiban, the clinical benefit of an early invasive strategy with routine catheterization/revascularization as indicated is supported by favorable projected cost estimates. (Level of Evidence: 2b)