Yôga and Breathing Techniques Training in Patients With Heart Failure and Preserved Ejection Fraction

Study Overview
=================
Brief Summary
-----------------
Current therapies for heart failure (HF) bring together strategies to improve quality of life and exercise tolerance, as well as to reduce morbidity and mortality. Some HF patients present changes in the musculoskeletal system and inspiratory muscle weakness, which may be restored by inspiratory muscle training, thus increasing respiratory muscle strength and endurance, maximum oxygen consumption (VO2), functional capacity, respiratory responses to exercise, and quality of life. Yoga therapies have been shown to improve quality of life, inflammatory markers, and VO2 peak in HF patients, mostly with reduced ejection fraction (HFrEF). However, the effect of different yoga breathing techniques in patients with HF with preserved ejection fraction (HFpEF) has yet to be assessed.

Detailed Description
-----------------
Yôga techniques without breathing control have shown to improve oxygen consumption in patients with HF, mostly HFrEF. However, almost half of HF patients present with HFpEF, and less studies have been performed in those patients. It has been recently demonstrated that HFpEF induces significant molecular, mitochondrial, histological, and functional alterations in the diaphragm and soleus, which were attenuated by exercise training . In cardiac disease and aging, several authors have shown a significant reduction in heart rate variability (HRV) in the frequency ranges associated with breathing, by using spectral analysis of heart rate (HR) and respiration.Therefore, the present randomized clinical trial (RCT) will be conducted in order to test the hypothesis that an program of yôga and specific breathing techniques with different ventilatory rhythms could be associated with improvement in inspiratory muscle responses, functional capacity, oxygen uptake efficiency slope (OUES), circulatory power, oscillatory ventilation, kinetics of oxygen consumption in the recovery period, distinct features of the autonomic nervous system, natriuretic peptides, echocardiographic measurements, and quality of life (QoL) in patients with HFpEF, with and without inspiratory muscle weakness (IMW).Therefore, the present randomized clinical trial (RCT) will be conducted in order to test the hypothesis that an 8-week program of yôga and specific breathing techniques with different ventilatory rhythms could be associated with improvement in inspiratory muscle responses, functional capacity, oxygen uptake efficiency slope (OUES), circulatory power, oscillatory ventilation, kinetics of oxygen consumption in the recovery period, distinct features of the autonomic nervous system, natriuretic peptides, echocardiographic measurements, and quality of life in patients with HFpEF, with and without IMW.

Official Title
-----------------
Yôga and Breathing Techniques Training in Patients With Heart Failure and Preserved Ejection Fraction: Study Protocol for a Randomized Clinical Trial

Conditions
-----------------
Cardiovascular Diseases, Heart Failure, Heart Failure, Diastolic

Intervention / Treatment
-----------------
* Other: Yôga
* Other: Breathing technique
* Other: Control group


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Adult patients with a diagnosis of HFpEF, functional capacity class II and III, who are being treated at a specialized HF clinic will be eligible. HF diagnosis will be established by clinical history (signs and symptoms), echocardiographic findings (left ventricular ejection fraction ≥ 50%) and medical records confirming management for HF. Exclusion Criteria: Pulmonary disease (forced vital capacity<80% of predicted and/or forced expiratory volume in 1 s <70% of predicted, significant mitral or aortic valve diseases, history of exercise-induced asthma, and active smoking or alcoholic.

Ages Eligible for Study
-----------------
Minimum Age: 45 Years
Maximum Age: 75 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Health Services Research
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intervention Yôga<br>Active protocol with yôga body movements performed along with respiratory vigorous, without contentions. Two sessions per week, with 45 minutes duration. | Other: Yôga<br>* Intervention observing respiratory frequency (RF) of 15- 20 respiratory cycles per minute (rcpm). A standardized 7-minute final relaxation .<br>|
| Experimental: Intervention breathing technique<br>Passive protocol, seated patient, no significant body movements. Breathing technique, with alternate nostril breathing combined to inspiratory and expiratory retentions.Two sessions per week, with 45 minutes duration | Other: Breathing technique<br>* Intervention uses diaphragmatic breathing, observing slow respiratory frequency, between 5-8 rcpm. A standardized 7-minute final relaxation.<br>|
| Experimental: Control group<br>Control group (standard pharmacological treatment). Patients will be oriented to keep their pharmacological routine and daily activities, with no structured exercises. They will have to return to the hospital for post-testing after 8 weeks from randomization. | Other: Control group<br>* Patients will be oriented to keep their pharmacological routine and daily activities, with no structured exercises. They will have to return to the hospital for post-testing after 8 weeks from randomization<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximal inspiratory pressure (PImax) | Inspiratory muscle strength by measuring maximal inspiratory pressure (PImax) | up to 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak oxygen uptake (peak VO2) | Peak VO2 will be considered the highest value of VO2 calculated in a 20-second-period during cardiopulmonary exercise testing (CPET) | Baseline and 8 weeks | 
| Vagal activity: heart rate variability- HRV | Twenty-four-hour ECG recordings will be obtained with a light digital recorder for to available of heart rate variability (HRV). | Baseline and 8 weeks | 
| Functional capacity through the 6-minute walk test (6MWD) | The maximum distance walked in 6 minutes of walking (6MWD).The distance traveled in the time of 6 minutes will be considered according to the predicted for gender and age of the patient. | Baseline and 8 weeks | 
| Quality of life Minnesota scores | Quality of life Minnesota scores as a specific inventory for patients with Heart Failure. | Baseline and 8 weeks | 
| N-terminal pro-brain natriuretic (NT-proBNP) | NT-proBNP test: N-terminal precursor of natriuretic peptide type B (Brain), clinical specimen by serum, sandwich-type electrochemiluminescence analysis method (COBAS E601-ROCHE). | Baseline and 8 weeks | 
| Echocardiographic - Ejection Fraction | Teichholz method: ejection fraction - study Inclusion criteria: EF≥ 50% . Establish a diagnostic measure of HF by confirming preserved ejection fraction and compare this measure at the end of the study. | Baseline and 8 weeks | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Yôga, Breathing Techniques, Heart Failure and Preserved Ejection Fraction