Chemoreflex Control of Sympathetic Activity in Patients With Coronary Artery Disease

Study Overview
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Brief Summary
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The investigators hypothesize that chemoreflex response of muscle sympathetic nerve activity (MSNA) during hypoxia and hypercapnia will be increased in coronary artery disease (CAD) patients and that the presence of obstructive sleep apnea (OSA) will potentiate these responses. And, that the exercise training would decrease the chemoreflex response of MSNA in these patients.

Detailed Description
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Forty patients with coronary artery disease, with (n=20) and without (n=20) obstructive sleep apnea will be studied. A healthy control, age-paired group (n=10) will be also evaluated. The patients will be submitted to a polysomnography and randomized for clinical follow-up or exercise training for four months. It will evaluated the autonomic function, chemoreflex control of sympathetic activity during hypoxic and hypercapnic maneuvers, endothelial function and inflammatory markers.

Official Title
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Effect of Exercise Training on Chemoreflex Control of Sympathetic Activity in Patients With Coronary Artery Disease and Obstructive Sleep Apnea

Conditions
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Coronary Artery Disease (CAD), Obstructive Sleep Apnea (OSA)

Intervention / Treatment
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* Other: Aerobic exercise training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of stable coronary artery disease; Age between 35-60 years, male and female; BMI <30 kg/m2 Not involved in a regular exercise program at least three months before the survey; Exclusion Criteria: Patients with angina and / or ischemia, Patients with diabetic neuropathy and / or ischemia of the lower limbs; Previous diagnosis of chronic pulmonary, neurological and orthopedic diseases, neoplasia, renal failure and insulin-dependent diabetes mellitus; Patients with acute myocardial infarction, cardiac surgery or hospitalization of cardiac origin six months before the study and carriers of pacemaker / implantable defibrillator; Patients with cardiac dysfunction (ejection fraction of left ventricle <40%); Current smoking and pregnant women.

Ages Eligible for Study
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Minimum Age: 35 Years
Maximum Age: 60 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control Group<br>Healthy control group for comparisons with coronary artery disease groups. | |
| No Intervention: CAD without OSA - Control<br>Clinical follow-up. | |
| Experimental: CAD without OSA - Intervention<br>Aerobic exercise training. | Other: Aerobic exercise training<br>* The patients will be submitted to four months of aerobic exercise training, three time a week.<br>|
| No Intervention: CAD with OSA - Control<br>Clinical follow-up. | |
| Experimental: CAD with OSA - Intervention<br>Aerobic exercise training. | Other: Aerobic exercise training<br>* The patients will be submitted to four months of aerobic exercise training, three time a week.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Chemoreflex control of MSNA at rest and during exercise. | Chemoreflex control of MSNA will be measured by microneurography technique during the gas mixture known exposure at rest and during exercise | baseline and after 4 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Endothelial Function | Endothelial Function will be measured by markers present in blood samples. | baseline and after 4 months | 
| Neurovascular Control | Neurovascular Control will be measured by venous occlusion plethysmography technique during the exposure mixture of gases known at rest and during exercise. | baseline and after 4 months | 
| Inflammatory markers | Inflammatory markers will be measured by markers present in blood samples. | baseline and after 4 months | 
| Quality of Life | Quality of life will be measured by the questionnaire Short-Form Health Survey (SF-36). | baseline and after 4 months | 
| Anxiety Trait and State | Anxiety Trait and State will be measured by the Spielberger state trait anxiety inventory (STAI). | baseline and after 4 months | 
| Symptoms of Depression | The level of symptoms of depression will be measured by the Beck scale. | baseline and after 4 months | 
| Mood State | Mood State will be measured by the profile of mood states (POMS) scale. | baseline and after 4 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Coronary artery disease, Chemoreceptors, Sympathetic nerve activity, Exercise