A Randomised controlled trial assessing the clinical and cost-effectiveness of Endovascular vs. Open revascularisation for common femoral artery steno-occlusive disease. The RAF Trial.

Background: Lower limb peripheral arterial disease (PAD) affects 1 in 5 people >55 years of age. It is the main cause of limb amputations. People with symptomatic PAD typically present with claudication (pain on walking) or leg gangrene (chronic limb threatening ischaemia [CLTI]). The common femoral artery (CFA) is the artery most often affected by in those with CLTI or claudication; 11,400 people require CFA revascularisation in the NHS yearly. CFA revascularisation can be performed via open surgery or newer endovascular treatments (minimally invasive). The latter might avoid some surgical complications like wound infections, but is known to be less durable and can be more expensive. Open CFA surgery vs. endovascular treatment have never been compared head-to-head in a high-quality trial assessing their clinical and cost-effectiveness, leading to unnecessary uncertainty for patients/clinicians, preventable amputations, deaths, and re-interventions across the NHS. Aim: Compare the clinical and cost effectiveness of open surgery vs. endovascular CFA treatment. Methods: Multicentre prospective randomised controlled trial (RCT) involving 504 adults with CLTI or lower limb claudication [Rutherford Stage >=3 or Fontaine Stage >= IIb(1)] who have steno-occlusive CFA disease requiring revascularisation, recruited from 24 NHS hospitals nationally (urban/rural areas). We will assess whether the established more invasive treatment (open CFA surgery) is superior to the newer endovascular treatment, as suggested by our lay co-applicants and patient advisory groups/workshops. The primary outcome measure will be a composite of death (all-cause) and/or re-intervention (major amputation or leg revascularisation) over a minimum of one year after randomisation. A variety of relevant secondary outcomes (quality-of-life, cardiovascular events, limb-related outcomes) will be reported and a full health economic analysis will be performed. Timeline: 51 months’ duration, allowing 9 months for approvals and pilot set-up, 6-month pilot, 18-month main recruitment phase (with a minimum of 12 months follow-up per individual patient). Anticipated impact & dissemination: This will be the first effectiveness-driven randomised study in this context, ending patient/experts’ uncertainty. RAF is expected to immediately shape guidelines and future practice regarding CFA treatment. Dissemination will take place via a trial-website, updates using infographics/text-summaries (lay and expert) on social media and through professional societies, and hybrid dissemination events to maximise attendance/engagement with participants/public/NHS. Results, published in journals and conferences, will be sent to guideline-committees/societies. PPI: Our two lay co-applicants and 42 lay participants in a national survey/workshops unanimously agreed on the importance of this research and shaped design. Most commented on clinical uncertainty, noting that it causes unnecessary stress/confusion for patients. A James Lind Alliance (JLA) Priority Setting Partnership (PSP) with 122 lay participants recognised this area as a top research-priority. Our two lay co-applicants will liaise with an independent advisory group to prepare trial documents, frequent summaries, support recruitment, and disseminate. We costed for two study events where 60 lay and expert participants will promote/disseminate nationally. PPI will be led by the CI, an expert co-applicant, and a coordinator.