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NCT02725060

Autoimmune Basis for Postural Tachycardia Syndrome

Enrolling by Invitation
NAAges 18–50Interventional
Vanderbilt University Medical Center
~58 participants
Updated 2025-11-12 on ClinicalTrials.gov
What's tested:phenylephrineisoproterenol25 micro-Ci of radiationPosture study with blood samples24-hour heart rhythm and blood pressure monitoringQuantitative Axonal Sudomotor Reflex Testing

At a glance

Recruiting sites
0 of 2 listed sites are recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Autoantibody levels
Measured over up to 10 minutes
+3 more outcomes measured

Conditions

Postural Orthostatic Tachycardia Syndrome
Postural Tachycardia Syndrome
Tachycardia
Arrhythmias, Cardiac
Autonomic Nervous System Diseases
Orthostatic Intolerance
Cardiovascular Diseases
Primary Dysautonomias

Explore related trials

Postural Orthostatic Tachycardia Syndrome

Where it's being run

2 sites across 2 states
Oklahoma1
Tennessee1

Study leadership

  • Luis Okamoto, MD · PRINCIPAL_INVESTIGATOR · Vanderbilt University Medical Center

Who to contact

This trial hasn't published a contact. View it on ClinicalTrials.gov

Do you actually qualify for this trial?

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Eligibility criteria

Inclusion

18-50 years old
Postural Tachycardia Syndrome: Heart rate increase \>30 bpm from supine within 10 min of standing, in the absence of orthostatic hypotension (\>20/10 mmHg fall in blood pressure), with chronic symptoms (\> 6 months), and in the absence of other acute cause of orthostatic tachycardia.
Able and willing to provide informed consent
Female premenopausal subjects must utilize adequate birth control and willingness to undergo serum beta-hCG testing
The subject must understand and be able to comply with the study procedures and restrictions.

Exclusion

Hypertension (\>150 mmHg systolic and \>100 mmHg diastolic) based on history or findings at screening.
Orthostatic hypotension (consistent drop in blood pressure \>20/10 mmHg with 10 min stand)
Pregnancy
Cardiovascular disease, such as myocardial infarction within 6 months, angina pectoris, significant arrhythmia (sinus tachycardia is not excluded), deep vein thrombosis, pulmonary embolism
History of serious neurologic disease
History or presence of significant immunological or hematological disorders
Clinically significant gastrointestinal impairment that could interfere with dietary compliance or drug absorption
Impaired hepatic function (aspartate amino transaminase and/or alanine amino transaminase \>1.5 x upper limit of normal range)
Impaired renal function (serum creatinine \>1.5 mg/dL)
Hematocrit \<28%
Current or concurrent disease that could affect the absorption, action or disposition of the drug, or clinical or laboratory assessments.
Any underlying or acute disease requiring regular medication that could possibly pose a threat to the subject or make implementation of the protocol or interpretation of the study results difficult
Inability to comply with the protocol

What this trial measures

  • Autoantibody levelsup to 10 minutes

    Blood samples collected while supine during the posture study will be analyzed for autoantibody positivity in POTS patients and control subjects.

  • Blood pressure after phenylephrine boluses1-2 minutes after bolus injections
  • Heart rate after isoproterenol boluses1-2 minutes after bolus injections
  • Orthostatic change in heart rateup to 10 minutes

    Difference between standing and supine heart rates.