Non-invasive Ventilation in Patients With Cardiac Heart Failure

Study Overview
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Brief Summary
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Patients with heart failure (HF) have a reduced exercise tolerance as the main result of the disease. This exercise intolerance is due to heart conditions, but also to dysfunction of the respiratory and peripheral muscles. Various factors such as chronic hypoxia, oxidative stress, nutritional depletion, peripheral muscle disuse, effects of medications, and sympathetic-vagal imbalance are major contributors to deconditioning. In this scenario, the use of non-invasive ventilatory support (NIV) arises as an adjunct to cardiac rehabilitation in the attempt to improve the functional capacity of patients, since NIV reduces work of breathing, improves oxygenation and increases lung compliance associated with improved ejection volume, due to increased intrathoracic pressure.

Detailed Description
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The main objective is to evaluate whether the use of NIV during Constant Treadmill Load Tests (CTLT) enhances exercise performance in Cardiac Heart Failure (CHF) patients on a treadmill. Each recruited patient will be evaluated on 4 occasions, with two different evaluations, an incremental test (IT) to find out the maximum aerobic speed reached and then, in randomized order, three CTLT at 85% of the maximum reached in the IT . Two of the three CTLT will be performed with the use of NIV, with PS (IPAP 10cmH2O and EPAP 5cmH2O) and CPAP (5cmH2O) mode, and the rest will be without the use of NIV. The main study variable will be the time tolerated on the treadmill during CTLT. Participants will have 5 minutes to adapt to NIV, 5-minute warm-up at 50% and then will start with the CTLT at 85% of the maximum aerobic speed reached in the IT. In total, each patient will be evaluated four times on four different visits. Sample size: For the sample's calculation, the maximum time in CTLC was chosen as the main study variable because it is a sensitive measure to detect changes after interventions (both pharmacological and non-pharmacological) and widely used in clinical trials. A minimum difference to detect of 100 seconds from previous literature was determined. Taking this data into account, and using a level of α of 0.05, a 1-β power of 0.80, and an effect size of 0.8, the sample size calculation for a paired t-test investigators found that at least 12 participants are needed. The calculation was made using the Gpower 3.1.9.7 software.

Official Title
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Is Non-invasive Ventilation Effective in Improving the Exercise Capacity in Patients With Cardiac Heart Failure?: A Randomized Controlled Trial

Conditions
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Heart Failure

Intervention / Treatment
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* Device: Non-invasive Ventilation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ejection fraction demonstrated by echocardiography ≤ 40% (in the last 12 months). NYHA functional class I - III. Clinical stability, defined as four weeks prior to the start of the study without hospitalizations. Signed informed consent. ≥ 18 years of age. Exclusion Criteria: Chronic obstructive pulmonary disease (COPD), unstable angina or significant arrhythmias. Myocardial infarction in the last 3 months, primary valve disease and anemia (hemoglobin under 13 g/dl for men or 12 g/dl for women). Patients who are smokers or ex-smokers of less than one year. Patients with cognitive impairment that prevents the correct understanding of the evaluations. Any neuromuscular or osteoarticular condition that limits test performance. Refusal to participate.

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Interventional, crossover, randomized.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Constant Treadmill Load Test (CTLT) using non-invasive ventilation (NIV)<br>Exercise capacity testing using PS in HF patients | Device: Non-invasive Ventilation<br>* Exercise capacity testing using the device<br>* Other names: Noninvasive Ventilations;|
| Experimental: Constant Treadmill Load Test (CTLT) using NIV<br>Exercise capacity testing using CPAP in HF patients | Device: Non-invasive Ventilation<br>* Exercise capacity testing using the device<br>* Other names: Noninvasive Ventilations;|
| Active Comparator: Constant Treadmill Load Test (CTLT) without NIV<br>Exercise capacity testing without NIV in HF patients | Device: Non-invasive Ventilation<br>* Exercise capacity testing using the device<br>* Other names: Noninvasive Ventilations;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline in exercise tolerance | Change in Maximun Walking time tolerated in a Constant Treadmill Load Test (CTLT) in seconds on treadmill between PS, CPAP and WNIT | At the end of exercise | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Dyspnea | Degree of dyspnea will be determined by this validated scale with a result between 0 and 10 points.0: Not at all 0.5: Very, very light (hardly noticeable) 1: Very light, 2: Light, 3: Moderate , 4: Somewhat intense, 5: Intense, 6: Between 5 and 7, 7: Very intense, 8: Between 7 and 9, 9: Very, very intense (almost maximum ), 10: Maximum. | At the end of exercise | 
| Change in Cardiac Rate | Difference in Cardiac Rate (beats per minute) using a pulse oximetry (Masimo Radical 7) and a heart rate monitor (Polar FT1) between PS, CPAP and WNIT | At the end of exercise | 
| Change in Oxygen Saturation | Change in Oxygen Saturation using a pulse oximetry (Masimo Radical 7) between PS, CPAP and WNIT | At the end of exercise | 
| Change in Global Comfort | Change in global comfort according to the device used with Visual Analogue Scale (VAS). The VAS is a 10 cm line with anchor statements on the left (very unpleasant) and on the right (very pleasant) 0-10cm. | At the end of exercise | 
| Change in Lower Limbs Fatigue | Change in Lower limbs fatigue perception using the Modified Borg Scale (Degree of fatigue will be determined by this validated scale with a result between 0 and 10 points.0: Not at all 0.5: Very, very light (hardly noticeable) 1: Very light, 2: Light, 3: Moderate , 4: Somewhat intense, 5: Intense, 6: Between 5 and 7, 7: Very intense, 8: Between 7 and 9, 9: Very, very intense (almost maximum ), 10: Maximum. | At the end of exercise | 
| Change in Blood Pressure | Change in Systolic and Dyastolic blood preassure in mmHg at the beginning and at the end. | At the end of exercise | 
| Change in Recovery heart rate | Change in heart rate (beats per minute) in the first minute, in the second minute and in the third minute after the test, using pulse oximetry (Masimo Radical 7) | At the end of exercise | 
| Change in the motive for stopping the test | Change in reason for stopping the test. A dichotomous question will be asked regarding the reason for stopping the test, whether it was due to dyspnea or lower limb fatigue. | At the end of exercise | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Rehabilitation, Exercise Test, Heart Failure, Aerobic Exercise