Acute Vascular Response to Exercise in Women With Nonobstructive Coronary Artery Disease

Study Overview
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Brief Summary
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The purpose of this study is to examine the acute effect of exercise on vascular function in women with nonobstructive coronary artery disease.

Detailed Description
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Women are more likely to have nonobstructive coronary artery disease (CAD) . The purpose of this study is to examine the acute effect of exercise on vascular function in women with nonobstructive coronary artery disease. Endothelium-dependent and -independent dilation, arterial stiffness and wave reflection will be measured at baseline and after walking on a treadmill at a slow pace for 47 minutes. Endothelium-dependent dilation will be measured using brachial artery flow-mediated dilation via high resolution ultrasonography. Endothelium-independent dilation will be measured using brachial artery dilation to sublingual nitroglycerin. Arterial stiffness and wave reflection will measured using applanation tonometry.

Official Title
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Acute Vascular Response to Exercise in Women With Nonobstructive Coronary Artery Disease

Conditions
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Nonobstructive Coronary Artery Disease

Intervention / Treatment
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* Other: Slow-paced walking


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: women with non-obstructive coronary artery disease documented within the past 5 years by coronary angiogram as no coronary arteries with stenosis greater than 50% lesions age 18 to 89 years able to complete maximal graded exercise test Exclusion Criteria: use of tobacco products within the previous six months use of oral contraceptives or hormone replacement therapy within the prior year pregnancy (positive urine pregnancy test) or lactation history of hepatic disease or infection with hepatitis B, C or HIV

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 89 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Slow-paced walking<br>Subjects will complete 47 minutes of walking at slow pace. | Other: Slow-paced walking<br>* Subjects will walk on a treadmill at a slow pace for 47 minutes<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in endothelium-dependent dilation | Brachial artery endothelium-dependent flow-mediated dilation to reactive hyperemia will be measured using high resolution ultrasonography. To determine flow-mediated dilation, brachial artery diameter and blood velocity will be measured before and after occluding the forearm for 5 minutes by inflating a cuff to 250 mmHg. | Baseline, 15 minutes after exercise and 1 hour after exercise | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in endothelium-independent dilation | To determine vascular smooth muscle responsiveness to nitric oxide, brachial artery diameter will be measured using high resolution ultrasonography before and after sublingual administration of 0.4mg nitroglycerin. | Baseline, 15 minutes after exercise | 
| Change in arterial stiffness and wave reflection | Aortic pulse wave velocity and augmentation index will be measured using applanation tonometry. | Baseline, 15 minutes after exercise and 1 hour after exercise |