Effects of Continuous Positive Airway Pressure (CPAP) in Heart Remodeling by Magnetic Resonance Imaging (MRI) (OSA-MRI)

The recruitment status of this study is unknown because the information has not been verified recently.
Verified July 2008 by University of Sao Paulo.
Recruitment status was  Active, not recruiting
Sponsor:
Collaborators:
Fundação de Amparo à Pesquisa do Estado de São Paulo
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Information provided by:
University of Sao Paulo
ClinicalTrials.gov Identifier:
NCT00727454
First received: July 28, 2008
Last updated: July 6, 2010
Last verified: July 2008
  Purpose

Obstructive sleep apnea (OSA) is independently associated with important heart remodeling that further contributes to overt heart failure. Recent evidences using echocardiogram suggested that continuous positive airway pressure (CPAP) has beneficial effects mainly on left ventricle parameters. However, the evidences regarding the right ventricle are scanty. In addition, no previous studies evaluated morphological and functional characteristics in OSA by magnetic resonance imaging (MRI) as well as the impact of CPAP.


Condition Intervention Phase
Obstructive Sleep Apnea
Device: CPAP
Device: No treatment
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single Blind (Investigator)
Primary Purpose: Treatment
Official Title: Effects of Continuous Positive Airway Pressure on Heart Remodeling in Patients With Obstructive Sleep Apnea: A Randomized Study With Cardiovascular Magnetic Resonance Imaging

Resource links provided by NLM:


Further study details as provided by University of Sao Paulo:

Primary Outcome Measures:
  • Right ventricle parameters: size and function. [ Time Frame: Baseline and after 3 months. ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Left Ventricle parameters: size and function [ Time Frame: Baseline and after 3 months. ] [ Designated as safety issue: No ]

Estimated Enrollment: 24
Study Start Date: July 2007
Estimated Study Completion Date: December 2010
Estimated Primary Completion Date: October 2010 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: 1 Control
No treatment
Device: No treatment
No treatment
Other Name: ---
Experimental: 2 CPAP
Continuous Positive Airway Pressure (CPAP) - REMStar Pro with C-Flex; Respironics, Inc., Murrysville, PA
Device: CPAP
Continuous Positive Airway Pressure (CPAP) during sleep for 3 months.
Other Name: CPAP REMStar Pro with C-Flex; Respironics, Inc.

Detailed Description:

The patients will be recruited from the Sleep Laboratory, Heart Institute (InCor), University of São Paulo Medical School. Male adults with a sleep study within 1 month showing severe OSA (>30 events of apnea and hypopnea per hour of sleep) and naive to treatment will be considered for the study. Age and body mass index matched controls will be recruited from the hospital staff and their relatives. All volunteers will be previously screening for the risk of OSA with Berlin Questionnaire. To minimize confounding risk factors, we will exclude subjects older than 60 years and those with a body mass index (BMI) >40 kg/m2, diabetes mellitus, hypertension, cerebrovascular disease, valvular heart disease, renal failure, current or past smoking history, and chronic use of any medication. Hypertension will be excluded after 3 or more normal blood pressure values (<140/90mm Hg) obtained on separate occasions with a conventional mercury sphygmomanometer.

Sleep Study. All participants will perform a standard overnight polysomnography. Apnea will be defined as complete cessation of airflow for at least 10 seconds, associated with oxygen desaturation of 3%. Hypopnea will be defined as a significant reduction (>50%) in respiratory signals for at least 10 seconds associated with oxygen desaturation of 3%. The apnea-hypopnea index will be calculated as the total number of respiratory events (apneas plus hypopneas) per hour of sleep. Normal values will be considered when the apnea-hypopnea index will be <5events/hour.

The participants will be randomly assigned to no treatment (control) or treatment with CPAP for 3 months, according to a computer-generated list of random numbers. At baseline and after 3 months, the participants will be submitted to cardiac MRI.

Magnetic resonance imaging methods. Participants will perform MRI examination on 1.5 - T GE CV/i system. Short and long-axis of the heart will be obtained during breath-hold and triggered on electrocardiogram pulse sequences. The first sequence will be a gradient-echo (steady-sate free procession) to assess left ventricular (LV) and right ventricular (RV) morphology and function. The second sequence will be an inversion-recovery prepared gradient-echo to obtain MDE (10 to 20 minutes after intravenous bolus of 0.2 mmol/Kg of gadolinium-based contrast). We will use the following parameters: repetition time 3.9/7.1ms, echo time 1.7/3.1 ms, flip angle 45º/20º, cardiac phases 20/1, views per segment 8/16 to 32, matrix 256 x 128/256 x 192, slice thickness 8/8mm, gap between slices 2/2mm and field of view 32 to 38/32 to 38 cm, inversion time none/150 to 250 ms, receiver bandwidth 125/31,25 kHz, number of excitations 1/2.

Blood Samples. Venous blood will be collected from all participants between 8 and 10 AM for the measurement of glucose, total cholesterol, low-density lipoprotein, high-density lipoprotein, and red blood cell count.

24-hour blood pressure monitoring. All participants will be submitted to a 24-hour blood pressure monitoring with a SpaceLabs device (model 90207).

  Eligibility

Ages Eligible for Study:   30 Years to 60 Years
Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Patients free of comorbidities with severe Obstructive Sleep Apnea by polysomnography.
  • Healthy volunteers (no obstructive sleep apnea and no comorbidities) matched for age, sex and body mass index.

Exclusion Criteria:

  • Subjects older than 60 years
  • Body mass index (BMI) >40 kg/m2
  • Diabetes mellitus
  • Hypertension
  • Cerebrovascular disease
  • Valvular heart disease
  • Renal failure
  • Current or past smoking history
  • Chronic use of any medication
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00727454

Locations
Brazil
Heart Institute (InCor)
Sao Paulo, Brazil, 05403-904
Heart Institute (InCor) - University of São Paulo Medical School
São Paulo, Brazil, 05403-904
Sponsors and Collaborators
University of Sao Paulo
Fundação de Amparo à Pesquisa do Estado de São Paulo
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Investigators
Principal Investigator: Luciano F Drager, MD, PhD Hypertension Unit, Heart Institute (InCor)
  More Information

No publications provided

Responsible Party: Geraldo Lorenzi-Filho, Heart Institute (InCor)
ClinicalTrials.gov Identifier: NCT00727454     History of Changes
Other Study ID Numbers: 3163/08/79
Study First Received: July 28, 2008
Last Updated: July 6, 2010
Health Authority: Brazil: Ethics Committee

Keywords provided by University of Sao Paulo:
Obstructive sleep apnea
CPAP
Heart remodeling
Cardiovascular disease
MRI

Additional relevant MeSH terms:
Apnea
Sleep Apnea Syndromes
Sleep Apnea, Obstructive
Dyssomnias
Nervous System Diseases
Respiration Disorders
Respiratory Tract Diseases
Signs and Symptoms
Signs and Symptoms, Respiratory
Sleep Disorders
Sleep Disorders, Intrinsic

ClinicalTrials.gov processed this record on October 21, 2014