Cost Effectiveness of Assessing Ultrasound Plaque Characteristics to Risk Stratify Asymptomatic Patients With Carotid Stenosis.

Background Imaging may play an important role in identifying high-risk plaques in patients who have carotid disease and who could benefit from surgical revascularization. We sought to evaluate the cost effectiveness of a decision-making rule based on the ultrasound imaging assessment of plaque echolucency in patients with asymptomatic carotid stenosis. Methods and Results We used a decision-analytic model to project lifetime quality-adjusted life years and costs for 5 stroke prevention strategies: (1) medical therapy only; (2) revascularization if plaque echolucency and stenosis progression to >90% are present; (3) revascularization only if plaque echolucency is present; (4) revascularization only if stenosis progression >90% is present; or (5) either plaque echolucency or stenosis progression is present. Risks of clinical events, costs, and quality-of-life values were estimated based on published sources and the analysis was conducted from a healthcare system perspective for asymptomatic patients with 70% to 89% carotid stenosis at presentation. Patients who did not undergo revascularization had the highest stroke events (17.6%) and lowest life-years (8.45), while those who underwent revascularization on the basis of either presence of plaque echolucency on ultrasound or progression of carotid stenosis had the lowest stroke events (12.0%) and longest life-years (14.41). The plaque echolucency or progression-based revascularization group had an incremental cost-effectiveness ratio of $110 000/quality-adjusted life years compared with the plaque echolucency-based strategy, which had an incremental cost-effectiveness ratio of $29 000/quality-adjusted life years compared with the joint echolucency and progression-based strategy. Conclusions Plaque echolucency on ultrasound can be a cost-effective tool to identify patients with asymptomatic carotid artery stenosis most likely to benefit from carotid endarterectomy.