Vasodilatory Effects of Light on Peripheral Artery Disease
University of Alabama at Birmingham
Summary
Subjects with a known diagnosis of peripheral artery disease as measured by an abnormal ankle brachial index (\<.9 or \>1.1) will undergo a single 5 min exposure of 670 nm light, 1 cm above the gastrocnemius muscle. Blood flow will be measured by infusion of ultrasound contrast and subsequent acquisition of ultrasound images. 2 blood samples will be collected for measurement of nitric oxide metabolites.
Description
The intent of this protocol is to measure blood flow in the gastrocnemius muscle in patients with documented peripheral artery disease before and after exposure to 670 nm light energy. The study consists of one visit. Blood flow measurement will be performed using contrast enhanced ultrasound, a method by which ultrasound contrast is continuously infused into the blood stream. Ultrasound records images in the area of interest and flow is related to the intensity of the contrast in each image. Blood will be drawn to measure nitric oxide metabolites. The study is designed to consist of one visit…
Eligibility
- Age range
- 18–85 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Participants will be subjects between the ages of 18 and 85 who have been diagnosed with peripheral artery disease. Men and women will be recruited for participation. All ethnicities will be included in this study. Diagnosis of peripheral artery disease is defined as an Ankle Brachial index of \<0.9 or greater than 1.1 either at rest or during treadmill exercise. Exclusion Criteria: * Exclusionary criteria include age under 18 years and over 85 years, those who are unable to understand the consent process , those who cannot read or speak English, active pregnancy, hyp…
Interventions
- DeviceRed Light (670 nm energy)
Light Emitting Diode light source (670 nm wavelength with output up to 75mW/cm2) will be placed over the gastrocnemius muscle. The light will be on for 5 minutes.
- DrugOctafluoropropane
All subjects will undergo infusion of octafluoropropane to measure peripheral blood flow.
Location
- Medical College of WisconsinMilwaukee, Wisconsin