Acute Effect of Transcutaneous Electrical Nerve Stimulation in Heart Failure

Study Overview
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Brief Summary
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The purpose of this study is to determine acute effect the transctutaneous electrical nerve stimulation in sympathetic and parassympathetic system in individuals with heart failure.

Detailed Description
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Heart failure (HF) is the inability of the heart to maintain adequate levels of blood supply to tissues. In recent years there has been an increased prevalence of heart failure (HF), in Brazil there are about two million people diagnosed with HF and 240,000 new cases per year. Thus, the IC constitutes the most serious problem now and in the fields of cardiology and public health. Sympathetic activity is increased and correlates with a worse prognosis and survival in these patients. Currently, the pharmacological blockade of the sympathetic system by chronic use of beta-blockers are commonly used to treat hyperactivity, but these interventions have side effects. The transcutaneous electrical nerve stimulation (TENS) has been used successfully to control pain in different clinical conditions and may be a noninvasive strategy to reduce drug and not the severity of increased sympathetic.

Official Title
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Acute Effect of Transcutaneous Electrical Nerve Stimulation on the Sympathetic and Parasympathetic Systems in Individuals With Heart Failure

Conditions
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Improvement of Cardiovascular Autonomic Control, Reduction of Levels of Catecholamines

Intervention / Treatment
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* Other: transcutaneous electrical nerve stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Possess stable heart failure grade II or III according to NYHA; Ejection fraction <40% determined by echocardiography; Having no change in drug therapy one month before being included in the study; There have been Myocardial Infarction (AMI) three months before study entry; Exclusion Criteria: Patients with grade IV heart failure according to NYHA; Acute respiratory; Unstable angina; Ventricular arrhythmia, unstable until three months before the start of the study; Pacemaker; Active smoking; Diabetes mellitus; And fever or infectious disease.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: tens<br> | Other: transcutaneous electrical nerve stimulation<br>* Application of low frequency (10-Hz) and high frequency (100-Hz) TENS, in two different days<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| differences in blood levels of catecholamines differences in blood levels of catecholamines differences in blood levels of catecholamines Differences in blood levels of catecholamines | For evaluation of catecholamines (epinephrine, norepinephrine and dopamine) will be held one antecubital venipuncture and collected into tubes containing ethylenediaminetetraacetic acid (EDTA). | one minute before and after transutaneous electrical nerve stimulation intervention (acute effect) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| improvement of heart rate variability | Temporal series of the tachogram, related to each selected segment were evaluated quantitatively considering the values of HR, total and normalized powers of low frequency (LF - 0.04 to 0.15 Hz) and high frequency (HF - 0.15 to 0.40 Hz) components of HRV and the sympato-vagal index (LF/HF). | one minute before and after transcutaneous electrical nerve stimulation intervention (acute effect) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transcutaneous electrical nerve stimulation, Sympathetic nervous system, Parasympathetic nervous system, heart rate