Heat Therapy for Peripheral Arterial Disease (HEATPAD)

Not Applicable

Not yet recruiting

• Conditions: Peripheral Arterial Disease; Intermittent Claudication; Critical Limb Ischemia
• Interventions: Device: AirGlove

• Registration Number: NCT06186505
• Lead Sponsor: Norfolk and Norwich University Hospitals NHS Foundation Trust

Brief Summary

Peripheral arterial disease (PAD) is a disabling condition, with symptoms of muscle cramping or pain on exertion, which can substantially reduce quality of life. This study aims to see if AirGlove device improves participants circulation. This is phase 1 study and will be taken in 3 parts: Phase 1a will be undertaken in 10 healthy volunteers to assess the effects of the AirGlove device on lower limb arterial flow, tissue perfusion, quality of life and product usability following a single session. Phase 1b will be undertaken in 20 participants with intermittent claudication to assess the effects of the AirGlove device on lower limb arterial flow, tissue perfusion, quality of life and product usability both in a single session and following a 12-week trial of heat therapy. Phase 1c will be undertaken in 10 participants with critical limb ischaemia Rutherford stage 4 (rest pain). Lower limb arterial flow, tissue perfusion, pain scores, quality of life, and product usability will be assessed both in a single session and following a 2-12 week trial of heat therapy.

Detailed Description

As people get older, the blood supply to the legs can get worse. This is caused by blockages in the main blood vessels in the leg. If left to get worse this can progress to ulcers and amputation. If treated early the blood supply can be improved. Currently patients are advised to exercise to improve their blood supply, however not all patients can do this. Recent work has shown that heat treatment could have a benefit in these patients to help improve walking distance and lower the risk of amputation. The studies so far have been limited to a one-off treatment, typically to the whole body rather than the affected leg. This study aims to use a device to warm the lower leg for a set amount of timeper day. The research team will look at the improvement in their walking distance and blood supply to the leg over a 12 week period.

The first phase of this study will be in healthy volunteers. They will undergo the trial protocol in a single session to assess acceptability of the trial protocol and identify potential barriers.

All patients invited into this study will be given the heat therapy device called AirGlove. This slides over the lower leg like a large sock, and hot air circulates within the sock itself. The research team will teach the patient how to use the device and they will then take it home for 12 weeks. At the start and end of the study patients will undergo tests to assess their walking distance, quality of life, pain, and to assess how much blood is getting down their leg.

This study will look at the role of heat therapy as an alternative to help improve their walking, potentially reducing the need for surgery, and saving legs.

Study Timeline

• Study First Submitted: 2021-11-05
• Status Verified: 2023-12
• Study First Submitted QC: 2023-12-15
• Last Update Submitted: 2023-12-15
• Study First Posted: 2024-01-02
• Last Update Posted: 2024-01-02
• Study Start: 2025-01-01
• Primary Completion: 2028-10-31
• Study Completion: 2028-12-31

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 40

Inclusion Criteria

Not provided

Exclusion Criteria

• Aged under 60 years (for Phase 1b and 1c only)
• Has known allergy to any trial product
• undergone previous surgical or endovascular intervention for peripheral arterial or endovascular intervention for peripheral arterial disease
• Alternative cause of leg pain
• Requires urgent revascularisation (<2 weeks)
• Significant leg ulceration/necrosis

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Phase 1a	AirGlove	Phase 1a will be undertaken in 10 healthy volunteers to assess the effects of the AirGlove device on lower limb arterial flow, tissue perfusion, and product usability following a single session. Measurements will be taken just prior to device application, and then again at the time of device removal.
Phase 1c	AirGlove	Phase 1c will be undertaken in 10 PAD patients with critical limb ischaemia Rutherford stage 4 (rest pain). Lower limb arterial flow, tissue perfusion, pain scores, quality of life, and product usability will be assessed both in a single session and following a 2-12 week trial of heat therapy.
Phase 1b	AirGlove	Phase 1b will be undertaken in 20 PAD patients with intermittent claudication to assess the effects of the AirGlove device on lower limb arterial flow, tissue perfusion, quality of life and product usability both in a single session, and following a 12-week trial of heat therapy. Measurements will be taken just prior to device application, and then again at the time of device removal at the start of the trial, and again at week 12 (in line with the recommended duration of SET).

Primary Outcome Measures

Name	Time	Method
Change in walking distance.	Participants in phases 1b and 1c will be measured at baseline and at a 12-week follow up visit. Participants in phase 1c will additionally have their walking distance measured at visits at 3 and 6 weeks.	Participants in phase 1b and 1c will undergo a 6-minute walk test to measure the initial claudication distance and maximum claudication distance.

Secondary Outcome Measures

Name	Time	Method
EQ-5D-5L Questionnaire score	Participants in phases 1b and 1c will be measured at baseline and at a 12-week follow up visit. Participants in phase 1c will additionally be measured at visits at 3 and 6 weeks.	Participants in phases 1b and 1c will complete the EQ-5D-5L questionnaire to assess quality of life.
Change in ankle brachial pressure index and toe pressure index.	Participants in phases 1b and 1c will be measured at baseline and at a 12-week follow up visit. Participants in phase 1c will additionally be measured at visits at 3 and 6 weeks.	ABPI measurements will also be undertaken at the same timepoints both pre and post device removal. These assessments will be undertaken prior to application of the AirGlove device, and just prior to device removal at 30 minutes. Further haemodynamic assessments will be undertaken 10 minutes, 20 minutes, and 30 minutes post device removal.
Change in tissue perfusion.	Participants in phases 1b and 1c will be measured at baseline and at a 12-week follow up visit. Participants in phase 1c will additionally be measured at visits at 3 and 6 weeks.	A laser doppler flowmeter will be used to measure change in tissue perfusion.
Change in arterial blood flow.	Participants in phases 1b and 1c will be measured at baseline and at a 12-week follow up visit. Participants in phase 1c will additionally be measured at visits at 3 and 6 weeks.	A doppler ultrasound will be used to measure blood volume flow and time adjusted mean velocity in the common femoral artery. Blood volume flow compromises the volume of blood crossing a single point in the common femoral artery, whereas time adjusted mean velocity is the rate of change of blood flow at this point. These assessments will be undertaken prior to application of the AirGlove device, and just prior to device removal at 30 minutes. Further haemodynamic assessments will be undertaken 10 minutes, 20 minutes, and 30 minutes post device removal. This will be assessed in this manner during each participant visit.
Intermittent Claudication Questionnaire score	Participants in phases 1b and 1c will be measured at baseline and at a 12-week follow up visit. Participants in phase 1c will additionally be measured at visits at 3 and 6 weeks.	Participants in phases 1b and 1c will complete the Intermittent Claudication Questionnaire to assess quality of life.