Effect of Lower Leg Heating and Transcutaneous Electrical Nerve Stimulation on Exercise Capacity in Patients With PAD

Salisbury University10 enrolled

Overview

Peripheral arterial disease (PAD) is characterized by poor circulation in the lower extremities that often provokes claudication (leg pain, numbness, and heaviness) with physical exertion. The aim of this research protocol is to determine the effect of two non-invasive treatment modalities on leg blood flow and exercise capacity in those with PAD. Specifically, we are measuring popliteal artery blood flow (Doppler ultrasound), toe oxygen saturation, ankle-brachial index (ABI), and 6-minute walking distance (6MWD) in men and women who have intermittent claudication (Fontaine Stage II; Rutherford Category 1-2) in response to 15 or 45 minutes of lower limb heating and transcutaneous electrical nerve stimulation (TENS).

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

SUPPORTIVE_CARE

Masking

SINGLE

Enrollment

Conditions

Peripheral Arterial Disease

Interventions

Lower leg transcutaneous electrical nerve stimulation (TENS)BEHAVIORAL

Bilateral lower leg transcutaneous electrical nerve stimulation (TENS) using burst mode at a 3Hz burst rate, 100Hz frequency, and 250 µs pulse duration, sufficient to evoke skeletal muscle contraction

Eligibility

Sex: ALLMin age: 40 YearsMax age: 85 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Intermittent claudication (Fontaine Stage II) * Resting ankle-brachial index (ABI) \< 0.90 * Ability to walk \> 60 meters in six minutes Exclusion Criteria: * Body mass index (BMI) \> 35 kg/m2 * Severe exercise limitations (more than PAD) due to co-morbidity * Taking illegal/recreational drugs * Uncontrolled hypertension (\>180/100 mmHg) * Severe peripheral neuropathy * Foot ulcers * Gangrene * Pregnant or breast feeding

Outcomes

Primary Outcomes

Distance walked during six-minute walk test

Distance walked during a self-paced six-minute walk

Time frame: 35 minutes post-intervention/control

Secondary Outcomes

Popliteal artery blood flow

Unilateral popliteal blood flow measured via Doppler ultrasound

Time frame: Pre-intervention baseline; 10, 20, and 30 minutes post-intervention/control

Time/distance to claudication during six-minute walk

Subjects give subjective ratings of claudication onset, if applicable, during six-minute walk test

Time frame: 35 minutes following each intervention and control period

Ankle brachial index (ABI)

Systolic blood pressures (SBP) are measured in the brachial arteries of both arms and in the posterior tibial and dorsalis pedis arteries of both ankles using a hand-held Doppler ultrasound probe and a sphygmomanometer

Time frame: Pre-intervention baseline and 20 minutes post-intervention/control

Toe oxygen saturation

A pulse oximeter is used to measure toe oxygen saturation in the big toe of each of the subject's feet