Cost-Utility Analysis of Mechanical Thrombectomy

Ischemic stroke is the third highest cause of death in the United Kingdom and a leading cause of disability. The overall incidence is postulated to increase over the next 5 years by the WHO. The economic burden of stroke is estimated at £9 billion per year in the United Kingdom ($38 billion in the United States) and is estimated to rise. Intravenous tissue-type plasminogen activator (IV-tPA) for cerebral arterial occlusion is the proven therapy for acute ischemic stroke. However, new strategies are increasingly involving adjunctive endovascular techniques, especially when fibrinolysis is contraindicated or has failed. Recently, 5 randomised controlled trials (Endovascular Treatment for Acute Ischemic Stroke in the Netherlands [MR CLEAN], Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke (ESCAPE), Extending the Time for Thrombolysis in Emergency Neurological Deficits Intra-Arterial (EXTEND-IA), Solitaire With the Intention for Thrombectomy as Primary Endovascular Treatment (SWIFT PRIME) Trial, and Endovascular Revascularization With Solitaire Device Versus Best Medical Therapy in Anterior Circulation Stroke Within 8 Hours (REVASCAT)) demonstrated superior benefit of adjunctive mechanical thrombectomy versus IV-tPA alone when there is a major vessel occlusion. This has been propagated by a new generation of thrombectomy devices, stent retrievers, which demonstrate a higher arterial recanalization rate and a better clinical outcome. More importantly, this is in patients with proximal large vessel occlusions who are known through the natural history of the disease to have a poor outcome. Stent retrievers have consistently shown significantly better angiographic, safety, and clinical outcome data than the Merci Retriever. Stent retrievers also seem to produce higher complete recanalization rates than Penumbra, although no head-tohead trial has been performed. A meta-analysis demonstrated that early vessel recanalization, using a range of methods, is Background and Purpose—Recently, 5 randomized controlled trials demonstrated the benefit of endovascular therapy compared with intravenous tissue-type plasminogen activator in acute stroke. Economic evidence evaluating stent retrievers is limited. We compared the cost-effectiveness of intravenous tissue-type plasminogen activator alone versus mechanical thrombectomy and intravenous tissue-type plasminogen activator as a bridging therapy in eligible patients in the UK National Health Service. Methods—A model-based cost-utility analysis was performed using a lifetime horizon. A Markov model was constructed and populated with probabilities, outcomes, and cost data from published sources, including 1-way and probabilistic sensitivity analysis. Results—Mechanical thrombectomy was more expensive than intravenous tissue-type plasminogen activator, but it improved quality-adjusted life expectancy. The incremental cost per (quality-adjusted life year) gained of mechanical thrombectomy over a 20 year period was $11 651 (£7061). The probabilistic sensitivity analysis demonstrated that thrombectomy had a 100% probability of being cost-effective at the minimum willingness to pay for a quality-adjusted life year commonly used in United Kingdom. Conclusions—Although the upfront costs of thrombectomy are high, the potential quality-adjusted life year gains mean this intervention is cost-effective. This is an important factor for consideration in deciding whether to commission this intervention. (Stroke. 2015;46:2591-2598. DOI: 10.1161/STROKEAHA.115.009396.)