A Study of Alveolar-Capillary Recruitment as a Screening and Tracking Tool for Patients with Pulmonary Arterial Hypertension


About this study

The purpose of this study is to determine if non-invasive measurement of blood flow to the lungs and the movement of gas from the lungs to the blood stream at rest and in response to low to moderate intensity exercise can be used as an assessment tool to allow for earlier detection and monitoring of individuals with pulmonary-arterial hypertension, and the response to drug treatments.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria

  • Aim 1 PAH patients
    • Diagnosed as having Group 1 PAH
      • Idiopathic
      • Hereditary
      • Drug or toxin induced
      • Associated with connective tissue disease
    • Confirmation of PAH by right heart catheterization
    • Capacity to consent
  • Aim 2 PAH patients
    • Physician approves the prescription of ambrisentan
    • Equal number that have/do not have other medications for PAH
  • Healthy controls

    • Free of any cardiovascular or pulmonary disease
    • Not currently taking any medication
    • Age- and sex-matched to PAH subjects
    • Capacity to consent

Exclusion Criteria

  • Receiving subcutaneous prostanoids
    • Other medications (oral phosphodiesterase type 5 inhibitors, oral or inhaled prostanoids, calcium channel blockers, or l-arginine) allowed as long as subject has been taking them for at least 3 months prior to commencing study
  • Pregnant or considering trying to become pregnant during  enrollment in the study

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Rochester, Minn.

Mayo Clinic principal investigator

Bruce Johnson, Ph.D.

Closed for enrollment

Scottsdale/Phoenix, Ariz.

Mayo Clinic principal investigator

Bruce Johnson, Ph.D.

Closed for enrollment

More information


Publications are currently not available

Study Results Summary

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Supplemental Study Information

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