Effects of CPAP on Ventricular Function Modifications

Study Overview
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Brief Summary
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To assess modifications of ventricular function induced by CPAP (Continuous Positive Airway Pressure).

Detailed Description
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There are still few studies on the effects of positive intra-thoracic pressure on ventricular function and spontaneous baroreflex sensitivity changes. Aim of the study is to evaluate, in patients with chronic heart failure with an ejection fraction < 40%, the modifications of ventricular function induced by CPAP (Continuos Positive Airway Pressure) application. All the measurament will be made in basal condition (without CPAP) and with CPAP administration at 10 cmH2O via an oro-nasal mask. Echocardiograpich evaluation: morphologic and hemodynamic evaluation is obtained with an echocardiographic exmination. Left ventricular measurement will be assessed in M-mode, under two dimensional guide) according to American Society of Echocardiography guidelines. Left ventricular ejection fraction will be assessed with Simpson method. Right ventricle morphology will be evaluated categorizing dimensions in a) normal, b) mild enlargement, c) severely increased and d) reduced. Right ventricle area will also be quantified in tele-diastole and in meso-sistole in apical 4 chamber and parasternal short-axis. Baroreflex control of heart rate was assessed by sequence method analysis of continuous blood pressure recordings obtained in basal condition and during CPAP. Data obtained by non invasive assessment of arterial pressure will be analized and values of arterial systolic, diastolic pressure and pulsatory period for each cardiac cicle will be registered. Assessment via sequence method is founded on identification, every 10 minutes, on sequences characterized by a progressive increase both in pressure both in RR interval or, conversely, by a progressive reduction of pressure and RR interval evaluated on 4 or more cardiac cicles.

Official Title
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Evaluation of the Effects of Intra-thoracic Positive Pressure Applicated With CPAP (Continuous Positive Airway Pressure) on Ventricular Function in Patients With Chronic Heart Failure: Modification Induced on Baroreflex Sensitivity

Conditions
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Heart Failure, Congestive

Intervention / Treatment
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* Device: CPAP (Continuous Positive Airway Pressure)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of heart failure Chronic heart failure Ejection fraction < 40% Exclusion Criteria: Age < 18 years Permanent atrial fibrillation Infiltrative cardiomyopathy Mild/moderate chronic obstructive lung disease Chronic heart failure Diabetes mellitus Chronic kidney failure

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

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: Supportive Care
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: CPAP (Continuous Positive Airway Pressure)|nan|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of modification of ventricular function and baroreflex sensitivity of heart rate after CPAP administration |  |  | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Heart Failure, Congestive, Continuous Positive Airway Pressure, Baroreflex, Echocardiography