Heat Therapy for Peripheral Arterial Disease (HEATPAD) (HEATPAD)

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.

Study Overview

• Status: Not yet recruiting
• Conditions: Peripheral Arterial Disease; Intermittent Claudication; Critical Limb Ischemia
• Intervention / Treatment: Device: AirGlove

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 Type: Interventional
• Enrollment (Estimated): 40
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Julie Dawson; Phone Number: 01603 647882; Email: julie.dawson@nnuh.nhs.uk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Participants in Phase 1a will be healthy volunteers. The inclusion criteria for this cohort are:

• Aged 18 or over
• ABPI within normal range (0.9 - 1.2)
• Negative Edinburgh Claudication Questionnaire

For Phase 1b and 1c inclusion criteria are:

• Capacity to provide informed consent
• Aged 60 or over
• ABPI <0.9
• Positive Edinburgh Claudication Questionnaire

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 Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Phase 1a; 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.	Device: AirGlove; AirGlove is a unique warming system developed to enable access to the veins in a patients arm for the delivery of intraveneous drugs by gently heating the patients arm up as it forces warm air through a double walled polythene glove. In this study, the device will be used on the leg of the participants as means of encouraging circulation to the area.; Other Names: GB001
Experimental: Phase 1b; 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).	Device: AirGlove; AirGlove is a unique warming system developed to enable access to the veins in a patients arm for the delivery of intraveneous drugs by gently heating the patients arm up as it forces warm air through a double walled polythene glove. In this study, the device will be used on the leg of the participants as means of encouraging circulation to the area.; Other Names: GB001
Experimental: Phase 1c; 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.	Device: AirGlove; AirGlove is a unique warming system developed to enable access to the veins in a patients arm for the delivery of intraveneous drugs by gently heating the patients arm up as it forces warm air through a double walled polythene glove. In this study, the device will be used on the leg of the participants as means of encouraging circulation to the area.; Other Names: GB001

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in walking distance.	Participants in phase 1b and 1c will undergo a 6-minute walk test to measure the initial claudication distance and maximum claudication 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.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in tissue perfusion.	A laser doppler flowmeter will be used to measure 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.
Change in arterial blood flow.	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.	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.
Change in ankle brachial pressure index and toe pressure index.	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.	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.
EQ-5D-5L Questionnaire score	Participants in phases 1b and 1c will complete the EQ-5D-5L questionnaire to assess quality of life.	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.
Intermittent Claudication Questionnaire score	Participants in phases 1b and 1c will complete the Intermittent Claudication Questionnaire to assess quality of life.	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.

Collaborators and Investigators

• Sponsor: Norfolk and Norwich University Hospitals NHS Foundation Trust
• Collaborators: GreenCross Medico Limited
• Investigators: Principal Investigator: Philip Stather, Mr, Norfolk and Norwich University Hospitals NHS Foundation Trust

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2025
• Primary Completion (Estimated): October 31, 2028
• Study Completion (Estimated): December 31, 2028

Study Registration Dates

• First Submitted: November 5, 2021
• First Submitted That Met QC Criteria: December 15, 2023
• First Posted (Estimated): January 1, 2024

Study Record Updates

• Last Update Posted (Estimated): January 1, 2024
• Last Update Submitted That Met QC Criteria: December 15, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Keywords: Healthy volunteers; Walking distance; Heat therapy; AirGlove
• Additional Relevant MeSH Terms: Pathologic Processes; Cardiovascular Diseases; Vascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Disease Attributes; Atherosclerosis; Chronic Disease; Ischemia; Peripheral Arterial Disease; Peripheral Vascular Diseases; Intermittent Claudication; Chronic Limb-Threatening Ischemia
• Other Study ID Numbers: 304872 (42-03-21)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No