NCT01730092 · National Institutes of Health Clinical Center (CC)
Natural History Study of Biomarkers in Pulmonary Arterial Hypertension
What this study is about
Background: \- High blood pressure in the lungs, known as pulmonary arterial hypertension (PAH), is a rare disorder. Some people have disease-associated PAH and some have PAH from an unknown cause. Researchers want to follow the natural history of all PAH patients to understand how PAH progresses in order to discover targets for future research into new treatments.
View original scientific description
Background: \- High blood pressure in the lungs, known as pulmonary arterial hypertension (PAH), is a rare disorder. Some people have disease-associated PAH and some have PAH from an unknown cause. Researchers want to follow the natural history of all PAH patients to understand how PAH progresses in order to discover targets for future research into new treatments. To further identify treatment targets, they will compare healthy volunteers to patients with PAH. Objectives: \- To study the natural history of PAH. Eligibility: * Individuals at least 18 years of age who have PAH. * Healthy volunteers at least 18 years of age. Design: * Participants with PAH will have periodic visits to the National Institutes of Health Clinical Center. After the first visit, they will return in 6 months and then yearly or every other year for as long as the study continues. * The first visit will take up to 3 days.
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.
Exclusion criteria
- based on race or sex. INCLUSION AND EXCLUSION CRITERIA FOR PAH SUBJECTS: Inclusion Criteria: The following parameters on RHC are required to meet the hemodynamic definition of PAH (NYHA/WHO Group I PH):
- mean pulmonary artery pressure of \> 25 mmHg at rest,
- pulmonary capillary wedge pressure of \< 15 mmHg (or a left ventricular end-diastolic pressure of \< 12 mmHg), and
- pulmonary vascular resistance of \> 3 Wood units (240 dyn s cm-5). For patients with suspected PAH (Group I PH) who have not undergone a RHC and/or additional testing to confirm the diagnosis, this testing will be completed as clinically indicated under a procedural consent. If clinically indicated (diagnostic) testing indicates that the subject with suspected PAH does not in fact meet standard criteria for PAH (Group I PH), then the subject will be removed from the study. Exclusion Criteria:
- Pregnant or breastfeeding women (all women of childbearing potential will be required to have a screening urine or blood pregnancy test)
- Age less than 18 years
- Inability to provide informed written consent for participation in the study INCLUSION AND EXCLUSION CRITERIA FOR HEALTHY CONTROL SUBJECTS: Inclusion Criteria for Control Subjects Any healthy man or woman who is the appropriate age and sex for matching to a PAH patient
- Must be eligible for MRI and Gadolinium Based MRI studies
- Must be eligible for CT and Iodine Based Contrast CT studies Exclusion Criteria for Healthy Control Subjects
- Current pregnancy or breastfeeding (All women of childbearing potential will be required to have a screening urine or blood pregnancy test)
- Electrocardiographic evidence of clinically relevant heart disease
- Symptoms of coronary or cardiac insufficiency
- More than one major risk factor for coronary artery disease (excluding age and sex)
- Obesity (defined as a body mass index \> 30 kg/m\^2)
- History of underlying conditions/risk factors associated with pulmonary hypertension such as collagen vascular disease, HIV infection, use of appetite suppressants, chronic liver disease or cirrhosis of the liver, chronic thromboembolic disease, congenital heart defects, hypoxemia and/or significant pulmonary parenchymal disease
- Systemic hypertension that is not well controlled (i.e. blood pressure at the time of screening \>140/90 mmHg in adults \< 60 years old or \>150/90 mmHg in adults 60 years or older) on medications. Subjects taking \> 2 anti-hypertensive medications will be excluded irrespective of their current blood pressure at time of screening
- Anemia, thrombocytopenia or coagulopathy
- Renal insufficiency (defined as an estimated glomerular filtration rate of \< 60 mL/min/1.73m\^2 of body surface area)
- Active tobacco use (\> 6 months) in the past ten years, any tobacco use within 3 months prior to the screening evaluation or any tobacco use prior to completion of the study
- Inability to provide informed written consent for participation in the study
- History of recreational drug use with the exception of marijuana (as long as marijuana use was \> 3 months from the time of study screening).
- Volunteers may be excluded if in the opinion of the study investigators they have a condition that may adversely affect the outcome of the study or the safety of the volunteer. Exclusion Criteria for MRI in Healthy Control Subjects and Subjects with PAH These contraindications include but are not limited to the following devices or conditions:
- Implanted cardiac pacemaker or defibrillator
- Cochlear Implants
- Ocular foreign body (e.g. metal shavings)
- Embedded shrapnel fragments
- Central nervous system aneurysm clips
- Implanted neural stimulator
- Any implanted device that is incompatible with MRI
- Unsatisfactory performance status as judged by the referring physician such that the subject could not tolerate an MRI scan. Examples of medical conditions that would not be accepted would include unstable angina and severe dyspnea at rest
- Subjects requiring monitored sedation for MRI studies
- Subjects with a condition precluding entry into the scanner (e.g. morbid obesity, claustrophobia, etc.)
- Subjects with severe back-pain or motion disorders who will be unable to tolerate supine positioning within the MRI scanner and hold still for the duration of the examination. Exclusion Criteria for Gadolinium Based MRI Studies Only:
- History of severe allergic reaction to gadolinium contrast agents despite pre- medication with diphenhydramine and prednisone
- Chronic kidney disease (an estimated glomerular filtration rate of \< 60 mL/min/1.73m\^2 of body surface area) Exclusion Criteria for Cardiac Computed Tomography in Healthy Control Subjects and Subjects with PAH: 1\) Subjects with a condition precluding entry into the scanner (e.g. morbid obesity, claustrophobia, etc.) Exclusion Criteria for Iodine Based Contrast CTA Studies Only:
- Serum creatinine \> 1.4 mg/dL
- History of multiple myeloma
- Use of metformin-containing products less than 24 hours prior to contrast administration
- History of significant allergic reaction to CTA contrast agents despite pre-medication with diphenhydramine and prednisone
Where
- Bethesda, Maryland
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 Jul 2, 2026 · Source of record for eligibility and locations