NCT07210606 · VA Office of Research and Development
Central Apnea in Heart Failure: Physiological Mechanisms to Inform Treatment
(CSA-HF)
What this study is about
Central sleep apnea (CSA) is common in patients with heart failure and those using opioid analgesics. Unfortunately, effective treatment of central apnea remains elusive, pressure therapy given the modest efficiency of positive airway pressure therapy.
View original scientific description
Central sleep apnea (CSA) is common in patients with heart failure and those using opioid analgesics. Unfortunately, effective treatment of central apnea remains elusive, pressure therapy given the modest efficiency of positive airway pressure therapy. The focus of this proposal is to identify mechanistic pathways to guide future therapeutic interventions for central sleep apnea based on the strong premise that multi-modality therapy will normalize respiration and hence mitigate adverse long-term consequences of CSA. The investigators' proposed studies will test combination therapies, including positive airway pressure (PAP) plus a pharmacological agent who have heart failure or are using opioid analgesics. The investigators anticipate that findings will inform future clinical trials to improve care and quality of life among Veterans suffering from central sleep apnea, which remains difficult to treat using existing approaches.
Interventions
DRUG
Trazodone + positive airway pressure (PAP) therapy
The central apnea index and the apneic threshold will be compared under two conditions: trazodone or placebo. In addition, participants will get PAP therapy during both the conditions.
DRUG
Oxygen + positive airway pressure (PAP) therapy
The central apnea index and the apneic threshold will be compared under two conditions: oxygen or room air. In addition, participants will get PAP therapy during both the conditions.
Primary outcome measures
Carbon dioxide (CO2) Reserve
Time frame: 120 days
CO2 reserve is the requisite change to induce central apnea to as the CO2 reserve, which can be positive or negative.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Men and women Veterans with central sleep apnea, defined as Apnea Hypopnea Index (AHI)\>15/hour with CAHI\>5/hour, will be included with the experiments
- Those with chronic, stable heart failure with reduced ejection fraction, receiving stable optimized guideline-based therapy and no hospitalizations or change in the medical regimen for the past 90 days before enrollment
Exclusion criteria
- Pregnant or breastfeeding females
- Moderate or severe obstructive or restrictive lung disease, including supplemental oxygen (O2) use
- Current treatment for central sleep apnea (CSA), including any form of positive airway pressure (PAP) in the past three months, or phrenic nerve situation
- Too ill to engage in the study procedures, inability to provide consent for participation
- A history of cardiac arrhythmia
- Alcohol or substance abuse (less than 90 days sobriety) or current participation in a treatment program
- Depression or a history of suicidality
- Severe insomnia (ISI\>21) or reported short sleep duration (\<6 hours)
- Positive airway pressure (PAP)-emergent central sleep apnea
- Lack of positive airway pressure (PAP) acceptance/adherence after a one-week home PAP trial after enrollment Additional Trazodone Exclusions:
- Prolonged QT on baseline electrocardiogram (ECG), using medications that inhibit CYP3A4
- Patients with severe renal impairment (glomerular filtration rate (GFR) \< 20 milliliters per minute/1.73 square meters) or end-stage renal disease
Where
- Detroit, Michigan
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Oct 13, 2026 · Source of record for eligibility and locations