Duplex UltraSound afTer Endo Revascularisation - Feasibility Randomised Control Trial (DUSTER)

Chronic Limb Threatening Ischaemia

Chronic limb threatening ischaemia, endovascular, ultrasound surveillance, randomised controlled trial

17, 000 people every year in the UK develop foot pain or wounds from blocked leg arteries. If left untreated, this can lead to amputation. Keyhole surgery is often used to balloon open the blockages before they can cause serious problems. However half of people over the next 2 years can develop further blockages, which can be identified by ultrasound scans of the leg arteries The aim of this clinical trial is to explore the benefits of regular ultrasound checks of the leg after keyhole surgery. In this study participants are randomly allocated to one of two groups. Half of participants will have standard clinic appointments with their vascular specialist at 1 month, 6 months and 12 months. The other half will have additional ultrasound scans of the leg arteries before their clinic appointments at 1, 6 and 12 months. We will then look at how many people attended the scans, whether the scans could be completed and how this affected decisions to have more surgery. At the end of the trial we will look at what happened to participants in both groups.

Phase 1: Feasibility RCT The study is a multi-site, randomised (1:1), controlled, open label, 2 arm, feasibility trial. DUSTER will be performed in 3 NHS vascular units at the following NHS Trusts: * Mid and South Essex NHS Foundation Trust * Imperial College Healthcare NHS Trust * Manchester University NHS Trust These sites comprise two urban and one rural site, in both the North, South and East of the country. This will help understand the effects of travel, ethnicity, and geography on attending appointments. Following NIHR INCLUDE guidance we have costed for translation of study materials / interpreters. Phase 2: Participant interviews Participants in the intervention arm will be invited to individual semi-structured interviews with members of the research team. The interviews will be held as per participants' preference on MS Teams, or via telephone, or in person, after a minimum 6 month follow up. The interviews seek to explore factors affecting adherence and the impact of integrated surveillance on patients. It will apply a Qualitative Descriptive Research (QDR) approach and aims to inquire into the experience of everyday living with chronic limb threatening ischaemia. QDR aims to provide broad insight into phenomena as experienced/lived by individuals and is widely used as the qualitative component in mixed-methodology studies especially in large-scale healthcare intervention studies to identify participants' perceptions of why ultrasound surveillance worked or did not work and how it might be better implemented. Using QDR in this manner can make modifications to how surveillance is delivered in a future HTA study, including behavioural modifications such as educational tools, automated reminders along with intervention modifications e.g. community-based scanning. Phase 3: Participant and stakeholder focus groups After the feasibility study, we will invite participants and stakeholders to 2 separate focus groups (face to face or MS teams-hybrid) to discuss potential secondary endpoints for a future HTA application (e.g. amputation free survival, quality of life and cost-effectiveness). These will be co-chaired with our lay co-applicants. HTA application drafting If progression criteria are met (see , Phases 1 -3 will feed into a draft HTA application in the final month of the study. The progression criteria are: * \>80% of ultrasound surveillance appointments are attended (\>72/90), AND * \>90% completion rate of at least one ultrasound scan component (\>81/90), AND * There is an increase of \>10% in re-interventions in ultrasound surveillance arm (\>3 patients).

United Kingdom