Pathophysiological Study of CSA in Adults With pLVEF

Study Overview
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Brief Summary
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Sleep apnea is classically divided into obstructive and central apnea, according to the persistence or otherwise of respiratory movements and the existence or not of pharyngeal collapse during apnea. However, there is evidence to suggest that some mechanisms are common to both types of apnea. Although the pathophysiology of obstructive apnea has been the subject of much work and now seems fairly well known, there is much less data on central apnea. These apneas can occur in different comorbid contexts. They are more frequently present in patients with heart failure, regardless of the etiology, and are associated with an adverse prognosis. The investigators hypothesize that the physiopathology of adult central apnea syndrome involves, in addition to ventilatory control abnormalities, upper airway abnormalities (VAS). The objective is to study the pathophysiology of central SAS, by first comparing the collapse of VAS of central apneic patients to those of patients with simple snoring or obstructive sleep apnea. In a second step, the investigators will analyze the cardiorespiratory coupling and will establish a map of the respiratory neural network in patients with central apnea. The investigators will focus their study on patients with central SAS (with preserved systolic heart function) due to the epidemiology of SAS.

Detailed Description
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A non-randomized case-control comparative monocentric physiopathology study with 3 parallel groups (one group of cases and two control groups) matched for age and body mass index (individual 1: 1: 1 match), to evaluate changes in the collapse of VAS in central apnea (central SAS case), compared to subjects without central apnea (obstructive SAS and single snoring). Primary objective : Evaluation of changes in upper airway collapse in patients with central sleep apnea syndrome with preserved LVEF heart failure (central SAS case), compared with snoring subjects free from sleep apnea syndrome (Simple snoring witnesses) Secondary objectives : Study the collapsibility of VAS according to the type of apnea (central SAS case versus obstructive SAS case). To study the association between the collapsibility of VAS and the global and central apnea-hypopnoea index (IAH). Study the association between the type of disorder (central SAS case versus simple snoring controls, central SAS case versus obstructive SAS controls) and cardiorespiratory coupling. Study the association between the type of disorder (central SAS case versus simple snoring controls, central SAS case versus obstructive SAS controls) and the CO2 response slope. Establish a map of the respiratory neural network in patients with central SAS with preserved ejection fraction. Study the association between the volumes in acoustic pharyngometry and the values of the Pcrit

Official Title
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Pathophysiological Study of Central Sleep Apnea in Adults With Preserved LVEF

Conditions
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Central Sleep Apnea

Intervention / Treatment
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* Other: Critical airway closure pressure (Pcrit) measurment
* Other: Acoustic pharyngometry
* Other: High density surface electroencephalogram neural mapping


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Male patient Age ≥18 years and ≤85 years With preserved LVEF heart failure (defined as LVEF ≥ 45% on ultrasound, MRI or isotopic ventriculography) Central SAS Group: Central to severe sleep apnea syndrome, defined by an apnea-hypopnoea index (IAH) greater than 15 per hour, of which at least 30% are central events; Obstructive SAS group: Moderate to severe obstructive sleep apnea syndrome, defined by an apnea-hypopnoea index (IAH) greater than 15 per hour, with a central event proportion of less than 30% Group snoring: absence of sleep apnea syndrome or mild sleep apnea syndrome (IAH <15 / h) in polysomnography, and presence of snoring on at least 30% of the night of recording. Free, informed and written consent Patient affiliated to a social security scheme (beneficiary or beneficiary) Exclusion Criteria: Impossibility of giving the subject informed information Participation in a research protocol involving the human person in the previous months if an exclusion directive is given in this protocol Use of respiratory or sedative depressant drugs, systemic corticosteroid therapy Impaired systolic function (defined by LVEF <45% in ultrasound, MRI or isotopic ventriculography) Unstable cardiovascular disease (cardiovascular event of less than one month) Recent surgery of the ENT sphere (less than 6 months) Central neurological pathology known Known, severe respiratory pathology (severity left to the investigator's discretion) Renal insufficiency (creatinine clearance <60 mL / min) or severe hepatic impairment Primary or secondary hemostasis disorder Patient on anticoagulant (antivitamin K, direct oral anticoagulant, heparin and related). Antiplatelet agents are allowed. Psychiatric pathology according to DSM-V criteria, unbalanced Pulsed saturation with oxyhemoglobin <88% at rest, on awakening Allergy to lidocaine Patient under tutorship or curatorship Failure to perform a prior medical examination Tympanic perforation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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Male

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: Other
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Central SAS cases<br>Patients with central apnea | Other: Critical airway closure pressure (Pcrit) measurment<br>* Pcrit is measured in awake patient, by applying a gradually decreasing pressure through a nasal NIV mask. Pcrit is defined as the pressure inducing airflow cessation in upper airway<br>Other: Acoustic pharyngometry<br>* Acoustic pharyngometry will assess the volume of the pharynx and determine if there is an obstacle in the upper airways.<br>Other: High density surface electroencephalogram neural mapping<br>* Mapping of the respiratory neural network will allow us to study the areas of the brain activated during breathing<br>|
| Other: Obstructive SAS controls<br>Patients with moderate to severe obstructive apnea (apnea-hypopnoea index ≥ 15 / h) | Other: Critical airway closure pressure (Pcrit) measurment<br>* Pcrit is measured in awake patient, by applying a gradually decreasing pressure through a nasal NIV mask. Pcrit is defined as the pressure inducing airflow cessation in upper airway<br>Other: Acoustic pharyngometry<br>* Acoustic pharyngometry will assess the volume of the pharynx and determine if there is an obstacle in the upper airways.<br>|
| Other: Snorers controls<br>Snorers controls : Patients with snoring, with or without mild obstructive apneas (index of apnea-hypopneas <15 / h) | Other: Critical airway closure pressure (Pcrit) measurment<br>* Pcrit is measured in awake patient, by applying a gradually decreasing pressure through a nasal NIV mask. Pcrit is defined as the pressure inducing airflow cessation in upper airway<br>Other: Acoustic pharyngometry<br>* Acoustic pharyngometry will assess the volume of the pharynx and determine if there is an obstacle in the upper airways.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Upper airway collapsibility is assessed by Pcrit value in central leep apnea and snoring | Pressure values of VAS (Pcrit) in patients in the Central SAS group and in the Obstructive SAS group | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Upper airway collapsibility is assessed by Pcrit value in central and obstructive sleep apnea | Pcrit value in cm H20 in the obstructive SAS group vs. central SAS group | 1 day | 
| The association between Pcrit (cm H20) and Apnea-Hypopnoea Index (events/h) | The association between Pcrit (cm H20) and Global and Central Apnea-Hypopnoea Index (events/h) | 1 day | 
| Chemosensitivity in central sleep apnea is assessed by CO2 response test | CO2 response slope (mL/min/mmHg) in CO2 response test via rebrething method | 1 day | 
| Cardiorespiratory coupling in central sleep apnea is assessed by RR measurment (mm on EKG) | Parameters of cardiorespiratory coupling to polysomnography | 1 day | 
| Neural network modifications in sleep apnea are assessed by frequency couplage indice | Respiratory neural network mapping in patients with central SAS with preserved ejection fraction through high density mapping | 1 day | 
| Volume and collapsibility characteristics in acoustic pharyngometry in the different groups |  | 1 day |