Evaluation of Pulmonary Perfusion Heterogeneity and Compliance in Patients With Pulmonary Hypertension Using Positron Emission Tomography Imaging
Condition: Pulmonary Arterial Hypertension
MeSH terms: Pulmonary Arterial Hypertension; Familial Primary Pulmonary Hypertension; Hypertension
Study type: Interventional

Summary: 
      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.
    

Detailed description: 
      Pulmonary hypertension (PH) refers to abnormalities in the pulmonary vasculature associated
      with a diverse group of disorders. The World Health Organization (WHO) classifies pulmonary
      hypertension into five groups, with Group I comprising pulmonary arterial hypertension
      (formerly referred to as "primary pulmonary hypertension"). Although not currently a part of
      the WHO classification, exercise-induced pulmonary arterial hypertension (EIPAH), defined by
      normal pulmonary artery pressures at rest and elevation of pulmonary pressures with exercise,
      is increasingly recognized as a distinct clinical entity. In some patients, exercise-induced
      pulmonary hypertension may represent a precursor for developing an established elevation in
      pulmonary pressures at rest that defines PAH. Functional PET imaging has not previously been
      utilized to quantify perfusion and vascular compliance in patients with pulmonary arterial
      hypertension. The overall goal of this study is to evaluate regional lung perfusion,
      perfusion heterogeneity, and vascular compliance in patients with both exercise-induced and
      resting pulmonary hypertension using functional positron emission tomography imaging.
      Ultimately, if quantifiable differences between healthy subjects and patients with PAH are
      detected with 13NN and 11CO labeled PET, functional PET imaging may provide a useful imaging
      modality in early diagnosis of pulmonary hypertension and monitoring response to therapy. In
      this pilot study, we will recruit 10 adult patients with pulmonary hypertension (5 with PAH
      and 5 with EIPAH) who are on stable PAH-specific therapy (if any), and 5 healthy controls.
    

Intervention name(s): CT imaging, functional PET imaging
Intervention type(s): Other
Intervention description(s): Physiology 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
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Other
Keywords: pulmonary hypertension, PET imaging, CT/PET