Cost-Effectiveness of Angioplasty versus Coronary Artery Bypass Grafts for High-Risk Patients [plenary]

Stroupe KT, Morrison D, Hlatky MA, Barnett PG, Cao L, Lyttle C, Hynes DM, Henderson WG. Cost-Effectiveness of Angioplasty versus Coronary Artery Bypass Grafts for High-Risk Patients [plenary]. Paper presented at: VA HSR&D National Meeting; 2006 Feb 1; Arlington, VA.

Objectives:Coronary revascularization is an expensive technique and among the most frequently performed in the United States. Estimates of healthcare costs associated with revascularizations range from $12 to $20 billion annually. A VA Cooperative Study randomized controlled trial (RCT) examined angioplasty versus coronary artery bypass graft (CABG) surgery for urgent revascularization of medically refractory angina patients at high risk of mortality from surgery. No previous RCTs have focused on this high-risk patient population. We examined the cost-effectiveness of angioplasty versus CABG for these high-risk patients. Methods:Of 454 patients at 16 VA medical centers, 445 were available for the economic analysis (218 angioplasty and 227 CABG patients). Total healthcare costs to VA were assessed from the healthcare provider's perspective. Effectiveness was measured by survival. The difference in average total cost and difference in survival between angioplasty and CABG patients were estimated at 3 and 5 years. The precision of the cost-effectiveness estimate was assessed using bootstrap methods. We determined the proportion of bootstrap replicants where angioplasty was the less costly and more effective (i.e, dominant) treatment.Results:After 3 years, average total costs were $60,274 for angioplasty versus $80,033 for CABG patients, a difference of $19,758 (95% confidence interval [CI], $12,587 to $27,640). The probability of survival at 3 years was 0.85 for angioplasty versus 0.81 for CABG patients (P = 0.17). Bootstrap analysis revealed angioplasty was less costly and more effective 96.7% of the time after 3 years. After 5 years, average total costs were $74,986 for angioplasty versus $92,342 for CABG patients, a difference of $17,356 (95% CI, $8,789 to $26,930). The probability of survival at 5 years was 0.79 for angioplasty patients versus 0.72 for CABG patients (P = 0.06). Bootstrap analysis revealed angioplasty remained less costly and more effective 96.6% of the time after 5 years.Implications:At 3 and 5 years, angioplasty was less costly and more effective for urgent revascularization of medically refractory, high-risk patients.Impacts:By indicating that angioplasty is less costly and more effective for high-risk patients, this study could impact choice of revascularization procedures both inside and outside of VA, resulting in substantial cost savings.