Clincosm LogoSign in Get a demo

Pathophysiology of Orthostatic Intolerance

Sponsor
Satish R. Raj (Other)
Overall Status
Recruiting
CT.gov ID
NCT00608725
Collaborator
National Institutes of Health (NIH) (NIH)
100
Enrollment
1
Location
2
Arms
348
Duration (Months)
0.3
Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The purpose of this study is to describe the mechanism of orthostatic intolerance, relying on cardiovascular physiological studies. The syndrome is of undetermined etiology, but the syndrome causes impairment of a number of young adults, females more than males, with symptoms of tachycardia, fatigue, lightheadedness, palpitations, blurred vision, chest discomfort, difficulty concentrating, and dizziness with the upright posture. It is believed that many different pathophysiological processes can give rise to this disorder.

Condition or Disease Intervention/Treatment Phase
  • Radiation: DAXOR
  • Procedure: QSweat
  • Drug: Intrinsic Heart Rate
 N/A

Study Design

Study Type:
Interventional
Anticipated Enrollment :
100 participants
Allocation:
Non-Randomized
Intervention Model:
Parallel Assignment
Masking:
None (Open Label)
Primary Purpose:
Diagnostic
Official Title:
Pathophysiology of Orthostatic Intolerance
Study Start Date :
Dec 1, 1996
Anticipated Primary Completion Date :
Dec 1, 2025
Anticipated Study Completion Date :
Dec 1, 2025

Arms and Interventions

Arm Intervention/Treatment
Other: Patients

Patients with orthostatic intolerance

Radiation: DAXOR
131-I-Human Serum Albumin Blood Volume Assessment Kit
Other Names:
  • Volumex

    • Procedure: QSweat
    Quantitative Sweat Testing
    Other Names:
  • QSART
  • Quantitative Axonal Sudomotor Reflex Testing

    • Drug: Intrinsic Heart Rate
    Atropine 0.04 mg/kg IV in divided doses Propranolol 0.2 mg/kg IV in divided doses
    Other Names:
  • Inderal
  • IHR

    		•
    Other: Healthy Control Subjects

    Healthy subjects to determine "normal" response

    Radiation: DAXOR
    131-I-Human Serum Albumin Blood Volume Assessment Kit
    Other Names:
  • Volumex

    • Procedure: QSweat
    Quantitative Sweat Testing
    Other Names:
  • QSART
  • Quantitative Axonal Sudomotor Reflex Testing

    • Drug: Intrinsic Heart Rate
    Atropine 0.04 mg/kg IV in divided doses Propranolol 0.2 mg/kg IV in divided doses
    Other Names:
  • Inderal
  • IHR

    		•

    Outcome Measures

    Primary Outcome Measures

    1. Physiological abnormalities in orthostatic intolerance [1 day]

    Secondary Outcome Measures

    1. blood volume [1 day]

    2. intrinsic heart rate [1 hour]

    3. quantitative sweat testing [2 hours]

    4. residual sympathetic function after pharmacological autonomic blockade [3 hours]

    5. norepinephrine spillover [3 hours]

    Eligibility Criteria

    Criteria

    Ages Eligible for Study:
    18 Years to 80 Years
    Sexes Eligible for Study:
    All
    Accepts Healthy Volunteers:
    Yes
    Inclusion Criteria:
    • Orthostatic intolerance
    Exclusion Criteria:
    • Inability or unwillingness to give informed consent

    Contacts and Locations

    Locations

    Site City State Country Postal Code
    1 Vanderbilt University Nashville Tennessee United States 37232

    Sponsors and Collaborators

    • Satish R. Raj
    • National Institutes of Health (NIH)

    Investigators

    • Principal Investigator: David Robertson, MD, Vanderbilt University

    Study Documents (Full-Text)

    None provided.

    More Information

    Publications

    None provided.
    Responsible Party:
    Satish R. Raj, Assistant Professor of Medicine & Pharmacology, Vanderbilt University Medical Center
    ClinicalTrials.gov Identifier:
    NCT00608725
    Other Study ID Numbers:
    • 8398
    • NIH HL56693
    First Posted:
    Feb 6, 2008
    Last Update Posted:
    Sep 8, 2021
    Last Verified:
    Sep 1, 2021
    Keywords provided by Satish R. Raj, Assistant Professor of Medicine & Pharmacology, Vanderbilt University Medical Center
    heart rate
    blood pressure
    blood volume
    sympathetic nervous system
    orthostatic tachycardia
    orthostatic intolerance
    POTS
    Additional relevant MeSH terms:
    Orthostatic Intolerance
    Postural Orthostatic Tachycardia Syndrome
    Tachycardia
    Propranolol

    Study Results

    No Results Posted as of Sep 8, 2021