Cost-Effectiveness of Coronary Artery Bypass Surgery Versus Medicine in Ischemic Cardiomyopathy: The STICH Randomized Clinical Trial

BACKGROUND: The STICH Randomized Clinical Trial (Surgical Treatment for Ischemic Heart Failure) demonstrated that coronary artery bypass grafting (CABG) reduced all-cause mortality rates out to 10 years compared with medical therapy alone (MED) in patients with ischemic cardiomyopathy and reduced left ventricular function (ejection fraction <= 35%). We examined the economic implications of these results. METHODS: We used a decision-analytic patient-level simulation model to estimate the lifetime costs and benefits of CABG and MED using patient-level resource use and clinical data collected in the STICH trial. Patient-level costs were calculated by applying externally derived US cost weights to resource use counts during trial follow-up. A 3% discount rate was applied to both future costs and benefits. The primary outcome was the incremental cost-effectiveness ratio assessed from the US health care sector perspective. RESULTS: For the CABG arm, we estimated 6.53 quality-adjusted life-years (95% CI, 5.70-7.53) and a lifetime cost of $140 059 (95% CI, $106 401 to $180 992). For the MED arm, the corresponding estimates were 5.52 (95% CI, 5.06-6.09) quality-adjusted life-years and $74 894 lifetime cost (95% CI, $58 372 to $93 541). The incremental cost-effectiveness ratio for CABG compared with MED was $63 989 per quality-adjusted life-year gained. At a societal willingness-to-pay threshold of $100 000 per quality-adjusted life-year gained, CABG was found to be economically favorable compared with MED in 87% of microsimulations. CONCLUSIONS: In the STICH trial, in patients with ischemic cardiomyopathy and reduced left ventricular function, CABG was economically attractive relative to MED at current benchmarks for value in the United States.