Abstract 171: Endovascular Thrombectomy May Be Cost-Effective for Patients With Large Core Ischemic Strokes: A Cost-Utility Analysis From the SELECT Study

Abstract

Background: Whether Endovascular Thrombectomy (EVT) is cost-effective in large ischemic core infarcts is unknown. Methods: In the prospective multicenter cohort study of imaging selection study (SELECT), large core was defined as CT ASPECTS < 6 or CTP ischemic core volume (rCBF<30%) ≥ 50 cc. A Markov model estimated costs, quality-adjusted life years (QALYs) and the Incremental Cost-effectiveness Ratio (ICER) of EVT compared to Medical Management (MM) over 20 years life expectancy. The lower and upper willingness to pay (WTP) per QALY were set at $50000 and $100000 and the Net Monetary Benefit (NMB) for EVT were calculated. A probabilistic sensitivity analysis (PSA) and cost-effectiveness acceptability curves (CEAC) assessed EVT cost-effective probability at WTP range values. Results: Of 361 enrolled, 105 had large core on CT or CTP (EVT 62, MM 43). 19 (31%) EVT patients achieved mRS 0-2 vs 6 (14%) MM (aOR: 3.27, 95% CI: 1.11-9.62; P = .03) with a shift towards better mRS (adj cOR: 2.12, 95% CI: 1.05-4.31, P = .04). Over 20 years EVT was associated with $26589 (C.I. $8672- $43978) incremental costs and a gain of 1.18 QALYs (C.I. 0.091- 2.2) per patient. EVT could avert 75 deaths over a theoretical cohort of 1000 patients (MM 861 vs EVT 786) thus the ICER of EVT compared to MM was $22400 per QALY (CI. $10109 - $66140), which is <$50000/QALY, Tab 1. EVT has a higher NMB compared to MM at the lower and upper WTP thresholds (EVT $86,3 and 271,4 million vs MM $53,6-$179,3 million), Tab 2. The PSA confirmed the results (fig 1). The CEAC showed 94% and 97% cost-effectiveness probability of EVT at the lower and upper values respectively of the maximum WTP, fig 2. EVT ICER in SELECT large core ($22400/QALY) was higher but still comparable to those in HERMES ($16882/QALY), DAWN ($7335/QALY) and DEFUSE3 ($14673/QALY), Tab 3. Conclusion: EVT may result in better outcomes and more lives saved in large core patients with higher QALYs, NMB and an acceptable ICER. The results were comparable to other EVT RCTs.