Effects of Iloprost on Hypoxic Pulmonary Vasoconstriction and Exercise Capacity at High Altitude

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00708565
Recruitment Status : Unknown
Verified June 2008 by VA Loma Linda Health Care System.
Recruitment status was:  Recruiting
First Posted : July 2, 2008
Last Update Posted : July 2, 2008
Information provided by:
VA Loma Linda Health Care System

Brief Summary:
The objective of this study is to determine if single dose administration of inhaled iloprost will reduce pulmonary artery pressure, reduce hypoxic pulmonary vasoconstriction and improve arterial oxygenation at rest and during exercise at high altitude.

Condition or disease Intervention/treatment Phase
Hypoxic Pulmonary Vasoconstriction Drug: iloprost Phase 1

Detailed Description:
Three major pathways in addition to oxygen modulate pulmonary vascular tone: 1) nitric oxide, 2) endothelin, and 3) prostacyclin. Considerable animal data support the role of the prostacyclin pathway in modulating hypoxic pulmonary vasoconstriction. In humans, prostacyclin and its analogs are important therapeutic agents in the treatment of pulmonary arterial hypertension (PAH). Despite the animal data and human data in PAH there is very little information about the use of iloprost to relieve hypoxic pulmonary vasoconstriction in healthy humans. Inhaled iloprost is an ideal agent to study the prostacyclin pathway due to its short duration of action (30-90 min) and elimination half-life of only 20-30 min. Individuals already participating in the Nepal Medex 2008 trip will be invited to participate in this research. Participants will be healthy active females or males, between 18-80 years of age, without known pregnancy or liver disease, who have a readily measurable tricuspid regurgitant velocity by Doppler echocardiography. If possible, we will attempt to identify a cohort of HAPE susceptible patients. Participants will undergo evaluation both at sea level (baseline) and at high altitude. Baseline (low altitude) testing will be performed in Bangor, North Wales, UK, and will include evaluation of pulmonary artery systolic pressures, cardiac output, and oxygen saturation at rest and during submaximal exercise before and after inhalation of iloprost. This strategy will then be repeated at an altitude of approximately 5000 meters in the Dhaulagiri region of Nepal.

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 50 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double (Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: Effects of Iloprost on Hypoxic Pulmonary Vasoconstriction and Exercise Capacity at High Altitude
Study Start Date : July 2008
Estimated Primary Completion Date : October 2008
Estimated Study Completion Date : October 2008

Resource links provided by the National Library of Medicine

Drug Information available for: Iloprost
U.S. FDA Resources

Intervention Details:
    Drug: iloprost
    Baseline echo measurements, cardiac output, pulse oximetry will be taken. Subjects will then be given one dose of inhaled iloprost. Post-inhalation, the measurements will be repeated at rest and with exercise.
    Other Name: Ventavis (brand name)

Primary Outcome Measures :
  1. Exercise capacity, pulmonary artery systolic pressure, cardiac output, oxygen saturation [ Time Frame: 6 months ]

Secondary Outcome Measures :
  1. Heart rate, tissue Doppler echocardiographic measurements [ Time Frame: 6 months ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  1. Age: 18 - 80 years
  2. Healthy physically active males or females
  3. Have readily measurable tricuspid regurgitation (TR) peak systolic velocity by continuous wave Doppler ultrasound

Exclusion Criteria:

  1. Unable to measure TR velocity
  2. Known liver disease
  3. Pregnancy
  4. Nitrates, cyclosporin, glyburide or other medications that in the opinion of the investigators could place subjects at increased risk of complications
  5. Any other medical condition that in the opinion of the investigators would place the subject at high risk

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00708565

United States, California
Jerry L. Pettis VA Medical Center Recruiting
Loma Linda, California, United States, 92357
Contact: James D Anholm, MD    909-583-6098   
Sponsors and Collaborators
VA Loma Linda Health Care System
Principal Investigator: James D Anholm, MD Jerry L. Pettis VA Mecial Center

Responsible Party: James D Anholm, MD, VA Loma Linda Healthcare System Identifier: NCT00708565     History of Changes
Other Study ID Numbers: 00769
First Posted: July 2, 2008    Key Record Dates
Last Update Posted: July 2, 2008
Last Verified: June 2008

Keywords provided by VA Loma Linda Health Care System:
To study the effects of iloprost on hypoxic pulmonary vasoconstriction at high altitude

Additional relevant MeSH terms:
Signs and Symptoms, Respiratory
Signs and Symptoms
Platelet Aggregation Inhibitors
Vasodilator Agents