Evaluation of the Six Minute Walk Test and Other Instruments in Heart Failure

Study Overview
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Brief Summary
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The purpose of this study is to assess functional capacity, quality of life and functioning of the autonomic nervous system in heart failure patients on beta-blocker treatment. The study hypothesis is that subjects who walk less distance, have lower quality of life and reduced heart rate variability during the six minute walk test.

Detailed Description
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Heart failure and its treatment result in symptoms such as pulmonary or systemic congestion causing impairment to the effort, psychological and social commitment, and impact on quality of life.

Official Title
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Evaluation of the Six Minute Walk Test, Heart Rate Variability and Quality of Life in Heart Failure Patients on Beta-blocker Treatment

Conditions
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Heart Failure, Autonomic Nervous System Imbalance, Heart Rate and Rhythm Disorders, Quality of Life

Intervention / Treatment
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* Other: Six minute walk test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Both sexes Different etiologies of Heart Failure Functional class I - III (NYHA) Left ventricular ejection fraction (LVEF) ≤ 50% No history of previous cardiac surgery In return for medical evaluation at the Amelio Marques Clinic, Hospital de Clinicas, Federal University of Uberlândia scheduled for the period from October 2012 to January 2013 Clinical stability observed by: heart rate, respiratory rate, blood pressure and arterial oxygen saturation Exclusion Criteria: Bad cognition compromising the understanding of tests Physical disability that compromise the performance in walk test Aortic aneurysm or any aortic deformity Patients with signs or symptoms of transient myocardial ischemia with angina pectoris and/or class IV by the Canadian Cardiovascular Society Classification Anomalous pressure behavior with hypertension > 180/100 mmHg Orthostatic hypotension (decrease > 15 mmHg ) with symptoms Arrhythmia with presence of complex ventricular extra systoles Tachycardia sinus at rest (HR > 120 beats/min) Atrioventricular block of 2nd or 3rd degree Subjects with pacemakers or implantable cardioverter-defibrillator (ICD) Functional class IV by the New York Heart Association Chronic organ dysfunction such as renal failure, respiratory or liver disease Active neoplasia over the past five years Commitment as general weakness, fever, other limiting factors (psychological, musculoskeletal) Feeling sick before the beginning of the Six minute walk test: intolerable angina or dyspnea, cramps in legs, staggering gait, excessive sweating (diaphoresis), pallor or ashen skin or SpO2 below 85% Voluntary desire of the patient to withdraw from research

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Chronic Heart failure group<br>All chronic heart failure group participants will perform two walk tests at the same day, with a heart rate monitor, and answer questionnaires about their perception of quality of life. Tests will be conducted on a single day, without follow up of patients. The six minute walk test will be performed according the American Thoracic Society Statement (2002). | Other: Six minute walk test<br>* If patients meet the criteria of the study, their data will be collected and will be interviewed to fill the Minnesota Living with Heart Failure Questionnaire (MLHFQ). They then will be taken to the hallway to perform the six minute walk test monitored with a heart rate monitor (Polar RS800 CX). After the test there will be a break of 20 to 30 minutes before repeating the walk test. During rest time, the patient will answer the general health survey questionnaire: Medical Outcome Study 36-item Short-Form Health Survey (SF-36).<br>* Other names: Heart rate variability (Polar RS800 CX);|
| Control Group<br>All control group participants will perform two walk tests at the same day, with a heart rate monitor, and answer questionnaires about their perception of quality of life. Tests will be conducted on a single day, without follow up of patients. The six minute walk test will be performed according the American Thoracic Society Statement (2002). | Other: Six minute walk test<br>* If patients meet the criteria of the study, their data will be collected and will be interviewed to fill the Minnesota Living with Heart Failure Questionnaire (MLHFQ). They then will be taken to the hallway to perform the six minute walk test monitored with a heart rate monitor (Polar RS800 CX). After the test there will be a break of 20 to 30 minutes before repeating the walk test. During rest time, the patient will answer the general health survey questionnaire: Medical Outcome Study 36-item Short-Form Health Survey (SF-36).<br>* Other names: Heart rate variability (Polar RS800 CX);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximum distance walked | The six minute walk test will be performed twice by each patient, at the same day. The collection period will extend until the sample is complete. This is an observational study because there is no follow up and reassessment of patients. | During six minute walk test | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Heart failure, Autonomic Nervous System, Heart rate, Quality of life