Functional MRI of the Lower Extremities

NCT03423316 — Not applicable, Unknown, 90 participants, Massachusetts General Hospital

ClinicalTrials Daily · Areas · Conditions · Drugs · Sponsors ·

Stress-rest Calf Muscle Perfusion: a Functional Diagnostic Test for Peripheral Arterial Disease (PAD)

Registry	NCT03423316
Status	Unknown
Phase	Not applicable
Study type	Interventional; non randomized, parallel, masking: none, diagnostic
Enrollment	90 (Estimated)
Sponsor	Massachusetts General Hospital (Other)
Conditions	Peripheral Arterial Disease
Interventions	Supervised exercise therapy (Behavioral)
Dates	start 2020-10-31 (estimated), primary completion 2021-07-01 (estimated), completion 2021-07-01 (estimated), first posted 2018-02-06, last updated 2020-09-16
Locations	1 site in United States

-Summary

In this project, the investigators propose to use high-resolution magnetic resonance imaging (MRI) to measure blood perfusion in different groups of calf muscle. This imaging approach is standard of care for evaluation of coronary artery disease (CAD), and has never been successfully applied to PAD. Preliminary results show distinct patterns of muscle perfusion between healthy and PAD patients, and thus great promise of the technique. The investigators will first verify the reproducibility of the technique, and then compare the calf muscle perfusion measures in PAD patients against healthy age-matched controls. This comparison will test the feasibility of detecting functional abnormality in PAD patients. After the baseline scans, the PAD patients will opt to undergo a 12-week supervised exercise therapy, and then a post-therapy MRI scan. Comparison of the pre- and post-therapy measurements will indicate how the therapy improves the calf-muscle perfusion, and how this perfusion change correlates with increases in patient's walking ability.

The long term goals of this project are to develop an improved diagnostic test for patients with PAD to predict who will benefit from therapeutic intervention. The MRI perfusion studies of calf muscle can be performed in conjunction with routine peripheral MR angiography to assess the functional significance of vascular stenosis.

Expand all sections · Collapse all

+Arms and interventions

Arm	Type	Interventions	Description
Healthy Controls	No intervention
Age-Matched Controls	No intervention		Subjects without PAD who have the same average age as the PAD patients
PAD Patients	Experimental	Behavioral: Supervised exercise therapy	Patients with PAD. Approximately 75% of PAD patients will be enrolled in the 12-week exercise therapy program.

Supervised exercise therapy (Behavioral): The therapy will be conducted three times each week for 12 weeks. Each session takes 1 hour, consisting of 5 minutes of warmup activities, 50 minutes of intermittent exercise, and 5 minutes of cool-down activities. Exercise consists of walking on a treadmill initiated at 2 mph and 0% grade, until claudication pain becomes moderately severe. After claudication pain subsides, the subject will restart the walk. At the end of the session, the total exercise duration will be recorded. After a patient is able to walk 8-10 minutes at the initial workload, the grade is increased by 1-2%, or the speed is increased by 0.5 mph as tolerated.

+Outcome measures

Primary outcomes

Stress-rest calf-muscle perfusion [Single visit (~90 minutes)]: Perfusion in the different calf muscle groups following exercises of low (rest) and high (stress) intensities
Perfusion changes following supervised exercise therapy [Before and after supervised exercise therapy (12 weeks)]: Change in stress-rest calf-muscle perfusion in PAD patients following the 12-week supervised exercise therapy

+Eligibility

Sex: All, ages: 18 Years to any, accepts healthy volunteers

Inclusion Criteria:

PAD patients with

* Intermittent claudication
* Ankle-brachial blood-pressure index (ABI) < 0.9

Exclusion Criteria:

* Estimated glomerular filtration rate (eGFR) < 30 ml/min/1.73m2
* Chronic pulmonary diseases
* Arthritis or other joint ailments

+Locations (1)

Facility	City	Country	Status
Massachusetts General Hospital	Boston, Massachusetts	United States