Abstract WMP7: Cost Effectiveness of Stent-retriever Thrombectomy Compared With Intravenous Thrombolytic Therapy Alone in Acute Ischemic Stroke Patients

Abstract

Introduction: Despite recent clinical trials demonstrating greater benefit with mechanical thrombectomy,thehigher cost associated with thrombectomy may limit its broad applicability. Objective: To determine the cost-effectiveness of stent-retriever thrombectomy plus IV-tPA versus IV-tPA alone in acute ischemic stroke patients. Method: The probability of individual primaryendpoints was obtained from the results of the SWIFT PRIME trial that compared98 acute ischemic stroke patients who received intravenous rt-PA alone with 98 patients who had mechanical thrombectomy with IV rt-PA (combination therapy). Total cost associated with each therapeutic intervention was derived from hospitalization cost and cost associated with primary and secondary endpoints of dependence, independence and death in each group. All probabilities, quality-of-life factors, and costs were estimated from the published literature. Costs were adjusted for inflation. A Monte Carlo simulation model was built to compare the health benefits and costs associated with combination therapy compared with IV-tPA alone. Overall costs and QALY’s were varied around probability values from the SWIFT PRIME trial to generate the simulation. Standard errors were used for generating variability.Incremental cost effectiveness ratio and cost effectiveness acceptability curves were also derived. Results: The cost effectiveness acceptability plane was completely situated in the south-east quadrant. This denotes that thrombectomy along with t-PA was both cheaper as well as improved Quality of life when compared to t-PA alone. Overall, QALYs for the thrombectomy and Iv-tPA and IV-tPA groups were 0.60(0.005) and 0.51(0.004), respectively (ranging from 0.0 [death] to 0.77 [independent]. Overall cost of combination therapy was $754,790 (12,303) and for IV-tPA alone was $933,190($7,495). The incremental cost effectiveness ratio was -$21,450 ($1,857)per QALY. The major costs in the tPA arm were a result of greater dependence at 90 days. Conclusion: In acute ischemic stroke patients and major arterial occlusion, stent-retriever thrombectomy in addition to intravenous t-PA,is both cost effective and improves quality of life.