Red Light Treatment in Peripheral Artery Disease

Vasodilatory Effects of Light on Peripheral Artery Disease

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.

Study Overview

• Status: Recruiting
• Conditions: Peripheral Artery Disease; Vasodilation; Claudication, Intermittent
• Intervention / Treatment: Device: Red Light (670 nm energy); Drug: Octafluoropropane

Detailed 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. However, if the protocol changes or the data quality initially collected is uninterpretable, subjects may be asked to return to allow for a standard methodology across all participants. In this case, the subjects who are asked to return will be subject to the same informed consent process a second time. The two visits will be at least one week apart to further reduce the already minimal risks of the study. This will also limit the number of study participants required to gather the necessary data to complete the study, thereby limiting the risks of the study to a smaller number of participants.

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

Contacts and Locations

• Study Contact: Name: Nicole L Lohr, MD,PHD; Phone Number: 414-996-3504; Email: nlohr@uabmc.edu

Study Locations

• United States
  • Wisconsin
    • Milwaukee, Wisconsin, United States, 53226
      • Recruiting
      • Medical College of Wisconsin
      • Contact: Nicole L Lohr, MD PhD; Phone Number: 205-996-3504; Email: nlohr@uabmc.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

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, hypersensitivity to perflutren contrast agents, pulmonary hypertension, active illicit drug use, untreated blood pressure over 160/95, sickle cell disease, or a history of intracardiac shunt. Additional exclusion criteria neurological diseases such as spinal stenosis, unspecified pain disorders, and any uncontrolled medical conditions.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Red Light treatment; This is a single arm design. All subjects will be enrolled to have peripheral blood flow measured before, during, and after red light exposure.	Device: Red 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.; Drug: Octafluoropropane; All subjects will undergo infusion of octafluoropropane to measure peripheral blood flow.; Other Names: Definity

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in blood flow	Video intensity units from contrast images will be converted to ml/min/g tissue	Baseline, 5 min of light, and up to 1 min after discontinuation of light

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in nitric oxide metabolites	NO measurement by ozone chemiluminescence	Baseline and 1 min after discontinuation of light

Collaborators and Investigators

• Sponsor: University of Alabama at Birmingham
• Investigators: Principal Investigator: Nicole L Lohr, MD,PHD, Medical College of Wisconsin

Study record dates

Study Major Dates

• Study Start (Actual): January 17, 2018
• Primary Completion (Estimated): December 31, 2024
• Study Completion (Estimated): May 1, 2025

Study Registration Dates

• First Submitted: June 27, 2017
• First Submitted That Met QC Criteria: June 27, 2017
• First Posted (Actual): June 29, 2017

Study Record Updates

• Last Update Posted (Estimated): April 18, 2024
• Last Update Submitted That Met QC Criteria: April 16, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Keywords: red light; vasodilation; nitric oxide
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Vascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Atherosclerosis; Peripheral Vascular Diseases; Peripheral Arterial Disease; Intermittent Claudication
• Other Study ID Numbers: 29388

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