Local Vasoconstriction in Postural Tachycardia Syndrome

NCT01210430 | Completed Early Phase 1 DMC

• 1 other identifier: 2R01HL074873-06A2
• Study Type: interventional
• Target: 74
• Locations: 1 country
• Sites: 1

Brief Summary

The investigators study will determine how often blood flow regulation abnormalities and abnormalities of sympathetic regulation produced by nitric oxide, angiotensin-II, and oxidative stress occur in POTS and the mechanism(s) of POTS in individual patients. Specific causes for POTS may vary from patient to patient. Patients will be compared to healthy control subjects. There is a treatment arm with a medication (losartan) that reduces the binding of angiotensin and increases NO. If the investigators know the specific biochemical mechanism the investigators may be able to offer further specific treatments to specific patients.

Conditions

Postural Tachycardia Syndrome

Keywords

Postural Tachycardia Syndrome; Orthostatic Intolerance; Reactive Oxygen Species; Oxidative Stress; Angiotensin II; Nitric Oxide; Blood Flow; POTS; Ascorbic Acid; Vitamin C; Losartan

Outcome Measures

Primary Outcomes (1)

• Orthostatic tolerance measured by the heart rate and blood pressure response to upright tilt

  2 months

Secondary Outcomes (1)

• Sympathetic activation and blood flow measured by sympathetic nerve recordings and Doppler blood flow in the leg

  2 months

Study Arms (3)

Losartan

ACTIVE COMPARATOR

Drug: Losartan

Ascorbic Acid (VItamin C)

ACTIVE COMPARATOR

Drug: Ascorbic Acid (Vitamin C)

Normal Saline

PLACEBO COMPARATOR

Drug: Normal Saline

Interventions

Losartan DRUG

Subjects will receive placebo or losartan for 4 weeks. Days 1-7, subjects will receive 12.5mg of Losartan or placebo. Days 7-14, subjects will receive 25mg of Losartan or placebo. Days 14-28, subjects will receive 50mg of Losartan or placebo.

Losartan

Ascorbic Acid (Vitamin C) DRUG

Subjects will receive 60mg/kg of Ascorbic Acid over 20 minutes followed by a maintenance infusion of 20mg/kg.

Also known as: Vitamin C

Ascorbic Acid (VItamin C)

Normal Saline DRUG

Subjects will receive 60mg/kg of normal saline over 20 minutes followed by a maintenance infusion of 20mg/kg of normal saline.

Normal Saline

Eligibility Criteria

• Age: 14 Years - 29 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• Cases will be between the ages of 14 and 29 years old referred for evaluation of orthostatic intolerance with 3 or more of the following symptoms for at least 3 months:
• dizziness
• nausea and vomiting
• palpitations
• fatigue
• headache
• exercise intolerance
• blurred vision
• abnormal sweating heat.
• Cases will have the diagnosis of symptomatic postural tachycardia made during a screening tilt table test.
• Cases will have normal physical examination, and normal electrocardiographic and echocardiographic evaluations.
• Only those free from heart disease, and from systemic illness will be eligible to participate.
• This excludes patients with illnesses and disease states known to be associated with endothelial cell dysfunction such as diabetes, renal disease, congestive heart failure, systemic hypertension, acute and chronic inflammatory diseases, neoplasm, immune mediated disease, trauma, morbid obesity and peripheral vascular disease.
• At the time of testing all patients and control subjects must refrain from vasoactive drugs for two weeks. Please check with us about any medication that you are taking.

You may not qualify if:

• An active medical condition that may explain the diagnosis
• A previous medical condition with undocumented resolution that may explain the diagnosis
• Past or present major psychiatric disorder
• Substance abuse within 2 years before onset of symptoms.

Sponsors & Collaborators

• New York Medical College: lead

Study Sites (1)

New York Medical College/Bradhurst building

Hawthorne, New York, 10532, United States

Location

Related Links

• The Center for Hypotension

MeSH Terms

Conditions

Postural Orthostatic Tachycardia Syndrome; Orthostatic Intolerance

Interventions

Losartan; Ascorbic Acid; Saline Solution

Condition Hierarchy (Ancestors)

Primary Dysautonomias; Autonomic Nervous System Diseases; Nervous System Diseases; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Biphenyl Compounds; Benzene Derivatives; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Imidazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Tetrazoles; Sugar Acids; Acids, Acyclic; Carboxylic Acids; Hydroxy Acids; Carbohydrates; Crystalloid Solutions; Isotonic Solutions; Solutions; Pharmaceutical Preparations

Study Officials

• Julian M Stewart, MD, PhD

  New York Medical College

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: DIAGNOSTIC
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor of Pediatrics

Study Record Dates

• First Submitted: August 19, 2010
• First Posted: September 28, 2010
• Study Start: July 1, 2010
• Primary Completion: June 1, 2015
• Study Completion: June 1, 2015
• Last Updated: June 10, 2021

Record last verified: 2021-06

Locations

US (1)