Pulmonary Arterial Hypertension | Evaluation of Pulmonary Perfusion Heterogeneity and Compliance in Patients With Pulmonary Hypertension Using Positron Emission Tomography Imaging

Pulmonary Arterial Hypertension research study

What is the primary objective of this study?

The purpose of the study is to find out how the blood flow changes in the lungs of people with pulmonary hypertension compared to healthy individuals without pulmonary hypertension. We would like to find out if there are differences in how blood flows when subjects are given a drug to dilate (widen) the arteries in their lungs and when they breathe extra oxygen. We will compare the results to when subjects don't receive any drug or extra oxygen. We hope that knowing about these differences will help us to better understand pulmonary hypertension and how to diagnose it earlier.

Who is eligible to participate?

Inclusion Criteria: - General 1. A signed and dated written informed consent is obtained from the subject. 2. The subject is capable of giving informed consent, which includes compliance with the requirements and restrictions listed in the consent form. 3. Available to complete the study. 4. Able to lie flat and able to perform a 30 second breath hold. - Patients with Pulmonary Hypertension 1. Subject is male or female aged = or > 18 years of age and < or = 70 years. 2. Subject is diagnosed with pulmonary arterial hypertension (WHO Group I, by right heart catheterization, mean PA pressure > 25 and PCWP < 15) or exercise-induced pulmonary hypertension (by right heart catheterization + Level III cardiopulmonary exercise testing, mean PAP > 30 and PCWP < 20 during exercise, but normal at rest), with the most recent of above diagnostic tests taking place within 12 months of study entry. 3. If patient has been on PAH-specific therapy, the therapy (agent and dose) has been unchanged for at least 3 months. Exclusion Criteria: - General 1. FEV1 and/or TLC < 70% predicted 2. PCWP > 15 mm Hg 3. Inability to perform the study (by primary MD or investigator assessment) 4. Subjects who have a past or present disease, which as judged by the Investigators may affect the outcome of this study 5. The subject has suspected history of drugs or alcohol abuse within the six months prior to the screening visit. 6. The subject has a positive pregnancy test. 7. The subject is unable to perform the respiratory manoeuvres necessary for the exam. 8. The subject has been exposed to a radiation dose over the past year that, when added to the radiation dose expected in this study, would exceed permissible yearly exposure as determined by the MGH radiation safety committee. - Subjects with Pulmonary Hypertension 1. Subject with clinical instability in the judgment of the investigator, or hospitalization for progression of pulmonary hypertension or right heart failure in the three months prior to the study. 2. Subjects in whom PAH therapy has been escalated (additional agent started) within 3 months of enrolment. 3. Subject with diagnosis of active tuberculosis, lung cancer, clinically overt bronchiectasis, allergic rhinitis, asthma, or COPD. 4. Subject that had a respiratory tract infection in the 4 weeks prior to the screening visit and throughout the duration of the study.

Which medical condition, disease, disorder, syndrome, illness, or injury is researched?

Pulmonary Arterial Hypertension

Study Interventions

Interventions can include giving participants drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available or noninvasive approaches such as surveys, education, and interviews.

Other:CT imaging, functional PET imagingPhysiology study using CT and functional PET imaging with 13NN and 11CO as radiotracers; images obtained before and after administration of inhaled nitric oxide and balance 80% oxygen as pulmonary vasodilators

Study Arms

Research studies and clinical trials typically have two or more research arms. An arm is a group of people who receive the same treatment in the study.

pulmonary hypertensionPatients with Group I pulmonary arterial hypertension and exercise-induced pulmonary hypertension to undergo CT imaging, functional PET imaging

healthy controlshealthy adults to serve as controls and to undergo the same study procedures: CT imaging, functional PET imaging

Study Status


Start Date: February 2013

Completed Date: March 15, 2018

Phase: N/A

Type: Interventional


Primary Outcome: Coefficient of variation of perfusion

Secondary Outcome: Vascular compliance

Study sponsors, principal investigator, and references

Principal Investigator: R. Scott Harris, M.D.

Lead Sponsor: Massachusetts General Hospital


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