Global Vascular Effects of Intermittent Pneumatic Compression-Pilot Study

Study Overview
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Brief Summary
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Intermittent pneumatic compression (IPC) of the lower extremities is a well-established technique for preventing deep vein thrombosis (DVT) and for treating venous stasis. IPC will be done in the home for 3 divided hours every day for 4 weeks. Lab tests, brachial ultrasound and MRI testing will be performed at baseline and after 4 weeks of daily IPC therapy. See detailed description for increase in healthy control subjects.

Detailed Description
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Intermittent pneumatic compression (IPC) of the lower extremities is a well-established technique for preventing deep vein thrombosis (DVT) and for treating venous stasis. Four categories of discoveries suggest that there may be potential of IPC to have global vascular benefits: IPC of the arms prevents DVT in legs; Nitric oxide released by vascular endothelial cells exerts protective effects on blood vessels; IPC increases nitric oxide availability locally in the lower extremity; Nitric oxide may be transported in blood and released at distant sites, particularly in a hypoxic setting. Therefore, we propose to test the effects of lower extremity IPC on global nitric oxide availability. We will enroll 4 categories of subjects. The first 3 categories will have only 1 hour of leg compression. Baseline cholesterol will be drawn for screening labs Brachial ultrasound and NO measurements will be done before and after 1 hr of IPC. No MRI will be done on these groups. Category 4 will have baseline labs and testing to include: Brachial ultrasound,NO measurements and MRI will be done before and after 4 weeks of daily IPC therapy. Category 1, 21-40 yrs healthy male or female Category 2, 50 yrs plus healthy males or females Category 3, 50 yrs plus aged matched controls with known heart disease Category 4, 50 yrs plus12 patients with coronary artery disease.

Official Title
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Global Vascular Effects of Intermittent Pneumatic Compression-Pilot Study

Conditions
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Coronary Heart Disease

Intervention / Treatment
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* Device: Intermittent pneumatic compression of the lower extremities


Participation Criteria
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Eligibility Criteria
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Category 1 subjects-healthy volunteers (no MRI required) INCLUSION (N-12) 21 -40 years male or female EXCLUSIONS History of CAD, MI, Cath,CABG,CTA, positive stress test HTN uncontrolled (SBP>140 or DBP>90) DM except diet controlled Cholesterol >200 at screening Smoking last 10 years Acute Medical Illness Inflammatory Phlebitis Infection lower limbs Recent lower limb surgery Category 2 subjects ( age matched without CAD)(no MRI required) INCLUSION (N-12) 50 plus male or female EXCLUSIONS History of CAD, MI, Cath,CABG,CTA, positive stress test HTN uncontrolled (SBP>140 or DBP>90) DM except diet controlled Cholesterol >200 at screening Smoking last 10 years Acute Medical Illness Inflammatory Phlebitis Infection lower limbs Recent lower limb surgery Category 3 subjects ( age matched with CAD)(no MRI required) INCLUSION (N-up to 5) 50 plus male or female documented CAD by cath, PTCI, CABG, CTA EXCLUSIONS History of CHF, DVT, PE Angina, active, needing nitrates Acute Medical Illness Inflammatory Phlebitis Infection lower limbs Recent lower limb surgery Category 4 subjects with MRI (original group) INCLUSIONS(N=12) 50 plus male or female documented CAD by cath, PTCI, CABG, CTA EXCLUSIONS History of CHF, DVT, PE Angina, active, needing nitrates Atrial Fib BMI>35 (MRI) MRI contraindications pregnancy Chronic Inflammatory Disease Acute Medical Illness Inflammatory Phlebitis Infection lower limbs recent lower limb surgery

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Intermittent leg compression<br>Intermittent leg compression daily for 3 hrs a day for 4 weeks | Device: Intermittent pneumatic compression of the lower extremities<br>* IPC will be done for 3 divided hours daily for 4 weeks<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brachial Flow Velocity | Brachial flow velocity measured using ultrasound. Units cm/sec. | Baseline | 
| Brachial Flow Velocity | Measured using ultrasound, units cm/sec. | 5 minutes into leg intermittent pneumatic compression | 
| Brachial Flow Velocity | Measured using ultrasound, units cm/sec. | 50 minutes into IPC | 
| Brachial Diameter | mm | baseline | 
| Brachial Diameter | mm | 1 hour after leg IPC | 
| Brachial Flow Dilation | Brachial Flow Mediated dilation, mm | baseline | 
| Brachial Flow Dilation | Brachial Flow Mediated dilation, mm | 1 hour after IPC | 
| Brachial Flow Dilation | Brachial Flow Mediated dilation, % | baseline | 
| Brachial Flow Dilation | Brachial Flow Mediated dilation, % | 1 hour after IPC | 
| Brachial Occlusion-mediated Constriction | Brachial Occlusion-mediated constriction measured via ultrasound, mm | baseline | 
| Brachial Occlusion-mediated Constriction | Brachial Occlusion-mediated constriction measured via ultrasound, mm | 1 hour after IPC | 
| Brachial Occlusion-mediated Constriction | Brachial Occlusion-mediated constriction measured via ultrasound, % | baseline | 
| Brachial Occlusion-mediated Constriction | Brachial Occlusion-mediated constriction measured via ultrasound, % | 1 hour after IPC | 
| Plasma Nitrite | nM | baseline | 
| Plasma Nitrite | nM | 1 hour after IPC | 
| Red Blood Cell Nitric Oxide | nM | baseline | 
| Red Blood Cell Nitric Oxide | nM | 1 hour after IPC | 
| Plasma S-nitrosothiols | nM | baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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IPC, EECP, intermittent pneumatic leg compression, nitric oxide, vascular endothelial cells, atherosclerosis