Cost-effectiveness of mechanical thrombectomy for acute ischemic stroke: generalizability across implementation settings.

BACKGROUND AND PURPOSE: Mechanical thrombectomy (MT) is a cost-effective treatment for large-vessel occlusion stroke. However, existing economic evaluations rely on restrictive assumptions regarding care pathways and resource use, limiting their applicability to real-world implementation. We evaluated the cost and cost-effectiveness implications of implementing MT across alternative, empirically observed clinical pathways in England to address this source of decision uncertainty. METHODS: A state-transition Markov model was populated with detailed United Kingdom clinical, outcome, and micro-costing data from five thrombectomy centres in England to compare MT with standard care. Alternative implementation scenarios reflected real-world variation in treatment pathways, including intervention-centre type, anaesthesia use, intensive care unit setting, and models of care. Scenarios were characterised using detailed pathway and cost data. Costs and quality-adjusted life-years were evaluated over a 5-year time horizon from National Health Service and societal perspectives. RESULTS: Mean procedural costs for MT were £6,135 (95% CI, £5,961-£6,318) per patient in the primary analysis, compared with £7,283 in the earlier protocol-based model. Over 5 years, MT was a dominant intervention, associated with both lower costs and improved health outcomes compared with standard care. Mean cost savings were £2,297 per patient, corresponding to an estimated annual saving of £52.6 million if all 22,908 potentially eligible patients were treated. Across all five centres and implementation scenarios, incremental cost-effectiveness ratios consistently remained below currently accepted willingness-to-pay thresholds per quality-adjusted life-year gained. CONCLUSIONS: Across a range of real-world clinical pathways, MT is highly likely to be a cost-saving alternative to current practice and cost-effective at current health opportunity-cost thresholds. These findings suggest that cost-effectiveness is robust to local variation in service delivery and support broader implementation of MT within the English stroke-care system.