Magnetic Resonance Imaging to Identify Characteristics of Plaque Build-Up in People With Peripheral Arterial Disease

Magnetic Resonance in Peripheral Arterial Disease

Peripheral arterial disease (PAD) is a disease in which fatty build-up, or "plaque," accumulates in the peripheral arteries. People with PAD often experience leg pain while walking due to reduced blood flow to the legs. This study will use magnetic resonance imaging (MRI) techniques to examine how specific features of plaque build-up in the leg arteries affect walking ability, leg strength, and balance in people with PAD.

Study Overview

• Status: Completed
• Conditions: Peripheral Vascular Diseases

Detailed Description

Plaque build-up caused by atherosclerosis increases the risk of blood clots, heart attack, and stroke. Blockages of plaque can occur in different areas of the body. PAD, a circulatory disorder in which blockages occur in the peripheral arteries, is one manifestation of atherosclerosis. Individuals with PAD experience reduced blood flow to the legs, which may cause leg pain while walking. This study will use MRI techniques to examine how characteristics of plaque build-up in the leg arteries change over time and how this change affects function, walking ability, leg strength, and balance in people with PAD. Results from this study may be used to shape future research studies that will attempt to identify more effective treatments for people with PAD.

This study will enroll people with PAD, as well as a smaller control group of people who do not have PAD. At an initial study visit, study researchers will interview participants to collect information about their medical history, daily activity level, walking ability, and mental functioning. Blood collection and a leg MRI will occur. Also, blood flow to the legs will be measured by comparing blood pressure measurements in the arms and legs. Leg function will be measured through a series of timed walks, leg strength exercises, and muscle power exercises. Questionnaires to assess participants' medical history will be completed by each participant's primary care doctor, and study researchers will review participants' medical records. Participants with knee pain will have a knee x-ray, and participants may wear a small device called an accelerometer for 1 week to monitor physical activity levels. During the second and third study visits, occurring at one and two year follow-up, blood flow, leg function, and leg strength will be measured. If participants cannot attend either study visit, researchers may visit participants at their home or conduct an interview over the phone. Study researchers may contact participants by phone once or twice a year for follow-up.

• Study Type: Observational
• Enrollment (Actual): 519

Contacts and Locations

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Northwestern University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Ankle Brachial Index less than 1 in participants

Description

Inclusion Criteria:

• For participants with PAD: lowest leg ankle-brachial index (ABI) less than or equal to 0.999
• For participants in the control group: lowest ABI between 1.00 to 1.30

Exclusion Criteria:

• Foot amputation, leg amputation, or gangrene
• Recent liver transplantation
• Requires oxygen on ambulation
• End stage renal disease
• Confined to a wheelchair
• Lives in a nursing home
• Low life expectancy
• Mini-Mental Status Exam (MMSE) score of less than 23 out of 30
• Communication difficulty due to language barriers
• Inability to tolerate MRI testing for any reason
• Six-minute walk performance limited primarily by pulmonary disease, legal blindness, or severe lower extremity arthritis

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Functional Performance: 6-minute walk performance	Baseline, 12 months, 24 months
MRI: Mean Plaque Volume	Baseline, 24 months

Secondary Outcome Measures

Outcome Measure	Time Frame
Four meter walking velocity (usual pace), four meter walking velocity (fastest pace), SPPB	Baseline, 12 months, 24 months
MRI: maximum plaque volume, external remodeling, mean percent lumen reduction, maximum percent lumen reduction	Baseline, 24 months

Collaborators and Investigators

• Sponsor: Northwestern University
• Collaborators: National Heart, Lung, and Blood Institute (NHLBI)
• Investigators: Principal Investigator: Mary M. McDermott, MD, Northwestern University

Publications and helpful links

General Publications

• Polonsky TS, Liu K, Tian L, Carr J, Carroll TJ, Berry J, Criqui MH, Ferrucci L, Guralnik JM, Kibbe MR, Kramer CM, Li F, Xu D, Zhao X, Yuan C, McDermott MM. High-risk plaque in the superficial femoral artery of people with peripheral artery disease: prevalence and associated clinical characteristics. Atherosclerosis. 2014 Nov;237(1):169-76. doi: 10.1016/j.atherosclerosis.2014.08.034. Epub 2014 Sep 2.
• McDermott MM, Carroll TJ, Kibbe M, Kramer CM, Liu K, Guralnik JM, Keeling AN, Criqui MH, Ferrucci L, Yuan C, Tian L, Liao Y, Berry J, Zhao L, Carr J. Proximal superficial femoral artery occlusion, collateral vessels, and walking performance in peripheral artery disease. JACC Cardiovasc Imaging. 2013 Jun;6(6):687-94. doi: 10.1016/j.jcmg.2012.10.024. Epub 2013 May 4.
• McDermott MM, Liu K, Carr J, Criqui MH, Tian L, Li D, Ferrucci L, Guralnik JM, Kramer CM, Yuan C, Kibbe M, Pearce WH, Berry J, McCarthy W, Liao Y, Xu D, Orozco J, Carroll TJ. Superficial femoral artery plaque, the ankle-brachial index, and leg symptoms in peripheral arterial disease: the walking and leg circulation study (WALCS) III. Circ Cardiovasc Imaging. 2011 May;4(3):246-52. doi: 10.1161/CIRCIMAGING.110.962183. Epub 2011 Mar 24.

Study record dates

Study Major Dates

• Study Start: October 1, 2007
• Primary Completion (Actual): January 1, 2012
• Study Completion (Actual): January 1, 2012

Study Registration Dates

• First Submitted: August 23, 2007
• First Submitted That Met QC Criteria: August 23, 2007
• First Posted (Estimate): August 24, 2007

Study Record Updates

• Last Update Posted (Estimate): April 9, 2014
• Last Update Submitted That Met QC Criteria: April 7, 2014
• Last Verified: April 1, 2014

More Information

Terms related to this study

• Keywords: PAD; Magnetic Resonance Imaging; Functional Impairment; Peripheral Arterial Disease
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Arteriosclerosis; Arterial Occlusive Diseases; Atherosclerosis; Vascular Diseases; Peripheral Arterial Disease; Peripheral Vascular Diseases
• Other Study ID Numbers: 1396; R01HL083064-01A2 (U.S. NIH Grant/Contract)