Leg Thermotherapy for Intermittent Claudication

Peripheral Artery Disease Clinical Trial

Official title:

Leg Thermotherapy for Intermittent Claudication

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02770547
• Other study ID #: 1601589496
• Status: Completed
• Phase: N/A
• Start date: May 30, 2016
• Est. completion date: December 14, 2018

Study information

• Verified date: January 2020
• Source: Indiana University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study proposes to evaluate the potential of leg thermotherapy as a non-pharmacological intervention that could improve the mobility and exercise tolerance of patients with intermittent claudication. Thermotherapy is a simple, easily applicable therapy that enhances exercise tolerance in patients with chronic heart failure by improving peripheral vascular endothelial function.

Description:

Peripheral arterial disease is characterized by atherosclerotic obstruction of the arteries in the lower extremities and affects approximately 10% of individuals older than 65 years. The most common clinical presentation of peripheral arterial disease is intermittent claudication, defined as leg pain caused by insufficient blood flow during walking. Individuals with intermittent claudication have severe exercise intolerance and markedly reduced levels of daily ambulatory activity. It is estimated that up to 40 million people worldwide suffer from intermittent claudication. Despite the increasing prevalence of this condition, few medical therapies improve mobility and exercise tolerance in these patients. An urgent need remains for the development of novel, non-invasive strategies that are more widely accessible and eliminate the need for supervision and frequent traveling to a clinical facility. The study proposes to evaluate the potential of leg thermotherapy as a non-pharmacological intervention that could improve the mobility and exercise tolerance of patients with intermittent claudication.

Subjects will complete baseline assessments for eligibility and ability to do study, including medical history, quality of life assessment, ankle-brachial measurement, leg MRI, venous blood draw, assessment of vascular function, and 6-minute walk test. Treatment consists of 3 treatment sessions per week for six consecutive weeks. Subjects will be randomized to low-heat therapy or high-heat therapy. Subjects will wear water-circulating pants through which the heat therapy will be administered during the treatment sessions. Outcome measurements (same as baseline assessments) will be repeated after 9 treatment sessions and after 18 treatment sessions (at the end of the treatment period).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 32
• Est. completion date: December 14, 2018
• Est. primary completion date: December 14, 2018
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 99 Years

Eligibility

Inclusion Criteria:

• Men and women with a stable symptomatic claudication for =6 months

• Ankle brachial index <0.9

Exclusion Criteria:

• Uncontrolled Diabetes (HbA1C > 8.5 measured within 3 months prior to date of consent)

• Heart Failure

• Chronic Obstructive Pulmonary Disease

• Critical limb ischemia (ischemic rest pain or ischemia-related non healing wounds or tissue loss

• Prior amputation

• Exercise-limiting comorbidity (i.e., angina, chronic lung disease, or arthritis)

• Recent (<3 months) infrainguinal revascularization (surgery or endovascular revascularization) or revascularization planned during study period.

• Plans to change medical therapy during the duration of the study

• Active cancer

• Chronic kidney disease (eGFR <30 by Modification of Diet in Renal Disease or Mayo or Cockcroft-Gault formula).

• HIV positive, active hepatitis B virus (HBV) or hepatitis C virus (HCV) disease.

• Presence of any clinical condition that in the opinion of the principal investigator makes the patient not suitable to participate in the trial.

• Peripheral neuropathy, numbness, or paresthesia in the legs.

• Morbid obesity BMI > 35.

• Open wounds or ulcers on the extremity.

MRI Exclusions:

• Cardiac pacemaker

• Implanted cardiac defibrillator

• Aneurysm clips

• Carotid artery vascular clamp

• Neurostimulator

• Insulin or infusion pump

• Implanted drug infusion device

• Bone growth/fusion stimulator

• Cochlear, otologic, or ear implant

• History of claustrophobia or who are unable to lie flat or who do not fit inside the bore of the scanner

Related Conditions & MeSH terms

• Intermittent Claudication
• Peripheral Arterial Disease
• Peripheral Artery Disease

Intervention

Device:
• Low Heat Thermotherapy
Subject will wear a High Density LCG (Liquid Circulating Garment). Water will be heated and circulated through the garment, which in turn supplies low heat to the subject's leg.
• High Heat Thermotherapy
Subject will wear a High Density LCG (Liquid Circulating Garment). Water will be heated and circulated through the garment, which in turn supplies high heat to the subject's leg.

Locations

Country	Name	City	State
United States	Indiana University Health Methodist Hospital	Indianapolis	Indiana
United States	Richard L. Roudebush VA Medical Center	Indianapolis	Indiana

Sponsors (2)

Lead Sponsor	Collaborator
Indiana University	American Heart Association

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Exercise Tolerance Assessed by Measuring Distance (m) Walked in 6-minutes	6-minutes walk test	Maximal walking distances on a 6mwt were obtained at weeks 3/6 and 6/6 of the study and compared to baseline values.
Primary	Blood Pressure	Participants have systolic, diastolic and mean blood pressure recording 14 times during baseline, week 3 and week 6 experimental sessions.	Average blood pressure taken every 5 minutes for 70 minutes was obtained at weeks 3/6 and 6/6 of the study and compared to baseline values.
Primary	Circulating Levels of Endothelin-1 (pg/mL)	Blood draw	Serum endothelin-1 levels were obtained at weeks 3/6 and 6/6 of the study and compared to baseline values.
Primary	Circulating Total Nitrate Levels (mmol)	Blood Draw	Serum total nitrate levels were obtained at weeks 3/6 and 6/6 of the study and compared to baseline values.
Secondary	Vascular Function Assessed by Leg MRI to Measure Peak Blood Flow in Popliteal Artery (ml/s)	Phase contrast magnetic resonance imaging was performed on the leg that the patient indicated to have the most severe claudication. An inflation cuff was placed around the thigh and inflated to 75 mmHg above resting brachial systolic pressure for 5 minutes. After 5 minutes of inflation, the cuff was release and an additional 10 minutes of imaging took place.	Peak flows after post-occlusive reactive hyperemia were obtained at weeks 3/6 and 6/6 of the study and compared to baseline values.
Secondary	Vascular Function Measured by Ankle-brachial Index - Calculated by Dividing Higher of Posterior Tibial or Dorsalis Pedis Blood Pressure (mmHg) by Higher of Right or Left Arm Systolic Blood Pressure (mmHg)	Ankle-brachial Index	Ankle-brachial index measures were obtained at weeks 3/6 and 6/6 of the study and compared to baseline values.
Secondary	Vascular Function Measuring Leg Cutaneous Vascular Conductance - Measured by Laser-doppler Flowmetry of the Skin	Laser-Doppler flowmetry of skin included placement of two heating probes on the anterior portion of the lower leg. The participant sat in a semi-recumbent position for 70 minutes while the temperature of the probe progressed from 33C to 39C at minute 10 and then to 43C at minute 50. Cutaneous vascular conductance was calculated at the average red blood cell flux during the final 2 minutes of the 39C heating portion divided by the mean arterial pressure taken at that time.	Maximal cutaneous vascular conductance values after 40 minutes of localized heating were obtained at weeks 3/6 and 6/6 of the study and compared to baseline values.
Secondary	Patient Reported Functional Health and Well-being Using 36-item Short Form Health Survey	36-item Short Form Health Survey. All scales are scored 1-100, with 1 being the poorest rating and 100 being the most optimal.	SF-36 questionnaires were administered at weeks 3/6 and 6/6 of the study and compared to baseline values.