Treatment of Central Sleep Apnoea in Patients With Heart Failure With Nasal High Flow Therapy (nHFT) (RELAX)

Treatment of Central Sleep Apnoea and Cheyne Stokes Respiration in Patients With Heart Failure: Nasal High-flow Oxygen Therapy?

To investigate whether nHFT is an effective treatment for patients with Chronic Heart Failure (CHF) and central sleep apnea (CSA). This study is a prospective one armed uncontrolled intervention pilot study investigating 4 weeks of nHFT at home in 10 patients with CHF and CSA.

Study population: 10 CHF patients with a Left Ventricular Injection Fraction(LVEF)< 45% and CSA/Cheyne Stokes Respiration (CSR) (apnoea/hypopnea index (AHI) > 15/hour); with at least 50% of the total number of events having a central character will be included. Patients with other diseases that will influence the respiratory system negatively during sleep i.e. chronic obstructive pulmonary disease (COPD Global Initiative of Obstructive Lung Diseases (GOLD) class 3 and 4), neuromuscular diseases and thorax cage deformities, as well as patients with CHF and CSA that use another form of treatment for their CSA at the time of inclusion, will be excluded. Intervention: nHFT will be titrated during a first titration night and used at home during the night for 4 weeks consecutively. Main study parameters/endpoints: To investigate the effect of nHFT with and without oxygen in reducing the apnoea/hypopnoea index during sleep after 4 weeks use nHFT. To investigate improvements in oxygen desaturation index, sleep quality and sleepiness, physical condition, left ventricular ejection fraction (LVEF), heart beat variability (HRV), N-terminal natriuretic peptide (NTproBNP) after 4 weeks use nHFT . Physiological condition; work of breathing and respiratory drive and measuring mouth-throat pressure.

The patient is hospitalized for one night. Initially patients will start with a flow rate of 10 L/min and when they are asleep during the night 90-minute periods of the following settings will be performed: Moderate flow rate: 20 L/min without additional oxygen (with room air, which means a fractional inspired oxygen (FiO2) of 21%) High flow rate: 40-50 L/min without additional oxygen Moderate flow rate: 20 L/min with FiO2 of 28% (comparable to the 2 L/min additional oxygen through a nasal cannula) High flow rate: 40-50 L/min with FiO2 of 28%

nHFT will be titrated during a first titration night and used at home during the night for 4 weeks consecutively

Transdiaphragmatic pressure as a marker of diaphragmatic true work of breathing, measured with the use of oesophageal and gastric balloon catheters

Assessed as the the length of time that it takes to accomplish the transition from full wakefulness to sleep, measured by means of electro-encephalogram (ECG) as part of the polysomnography

measured after 4 weeks of home nHFT treatment, as compared to the baseline ODI during spontaneous nocturnal breathing.

Inclusion Criteria: Moderate to severe CSA/CSR (AHI>15), in which CSA is defined when at least 50% of the apnoeas are central apnoeas Heart failure with reduced ejection fraction, defined as a LVEF < 45% of predicted Exclusion Criteria: Other diseases affecting respiration during sleep (COPD GOLD 3 or 4, neuromuscular disorders, thorax cage deformities) At the moment of the inclusion, the patient does not have a therapy to treat the CSA, such as continuous positive airway pressure (CPAP), oxygen, bilevel intermittent positive airway pressure (BiPAP) or acetazolamide.