Effect of Endothelin-1 Receptor Blockade on Circulating Endothelial Microparticles Levels in Patients With Pulmonary Hypertension

This study has been completed.
Information provided by:
University of California, San Francisco
ClinicalTrials.gov Identifier:
First received: May 6, 2008
Last updated: April 12, 2011
Last verified: March 2008

Pulmonary hypertension is a progressive and life threatening condition. It is characterized by severe remodeling of the pulmonary vessel wall, obstructive plexiform lesions, multi-focal thrombosis, and enhanced vasoconstriction. All of these characteristics contribute to increased pulmonary vascular resistance.

Circulating endothelial microparticles (EMPs) play an integral role in the pathogenesis and perpetuation of pulmonary hypertension. Levels of EMPs are considered a reliable biological parameter of endothelial injury.

We propose to assess the evolution of both circulating and pulmonary venous EMPs in patients with PH. Assessments will be made before and after initiation of Endothelin-1 (ET-1) Receptor blocker therapy, and correlated to their patterns with the changes in mean PAP, the 6 Minutes Walking Distance test, and circulating Endothelin-1 values. Measurements of the endothelial microparticle circulating levels (assessed by flow cytometry methods) will be made before, 1 month and 3 months after initiation of therapy.

Pulmonary Hypertension

Study Type: Observational
Study Design: Observational Model: Case-Only
Time Perspective: Prospective
Official Title: Effect of Endothelin-1 Receptor Blockade on Circulating Endothelial Microparticles Levels in Patients With Pulmonary Hypertension

Resource links provided by NLM:

Further study details as provided by University of California, San Francisco:

Estimated Enrollment: 20
Study Start Date: March 2008
Study Completion Date: February 2009
Primary Completion Date: February 2009 (Final data collection date for primary outcome measure)

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population

Precapillary Pulmonary Hypertension


Inclusion Criteria:

  • Patient's + 18 years with suspected pre-capillary pulmonary hypertension
  • Prescribed Endothelial - 1 receptor blocker

Exclusion Criteria:

  • Currently taking endothelium-active vasodilator therapy.
  • Hemoglobin and / or hematocrit level blood the lower normal limit.
  • Left ventricle dysfunction (LVEF <50%)
  • LV end-diastolic pressure > 15 mmHg)
  • Recent history (<3 months) of pulmonary embolism
  • Liver failure or abnormal liver function tests; aortic or mitral regurgitation or stenosis
  • Current medication with endothelin-1 receptor antagonist, prostacyclin analogues or type 5 phosphodiesterase inhibitors.
  • Subjects with conditions known to be associated with an increase in circulating endothelial microparticle numers, such as chronic renal failure (Creatinine Clearance < 50 ml/min/m2) acute coronary syndromes and uncontrolled system hypertension.
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00675051

United States, California
University of California
San Francisco, California, United States, 94143
Sponsors and Collaborators
University of California, San Francisco
  More Information

No publications provided

Responsible Party: Dr. Yerem Yeghiazarians, UCSF
ClinicalTrials.gov Identifier: NCT00675051     History of Changes
Other Study ID Numbers: H47369-31390
Study First Received: May 6, 2008
Last Updated: April 12, 2011
Health Authority: United States: Institutional Review Board

Keywords provided by University of California, San Francisco:
To determine if there is a trans-pulmonary gradient in the levels of EMPs in patients with PH
To determine if the EMPs measured at the pulmonary capillary wedge position correlates even more strongly with the severity of PH than the circulating levels
To determine if PH therapy with ET-1 receptor blocker will modify EMPs levels

Additional relevant MeSH terms:
Hypertension, Pulmonary
Cardiovascular Diseases
Lung Diseases
Respiratory Tract Diseases
Vascular Diseases

ClinicalTrials.gov processed this record on October 21, 2014