Adrenocorticotropic Hormone Stimulation in Postural Orthostatic Tachycardia Syndrome (POTS)

• ClinicalTrials.gov Identifier: NCT01764711
• Recruitment Status: Active, not recruiting
• First Posted: January 9, 2013
• Last Update Posted: May 3, 2021
• Sponsor: Vanderbilt University
• Collaborators: National Institutes of Health (NIH); National Heart, Lung, and Blood Institute (NHLBI)
• Information provided by (Responsible Party): Alfredo Gamboa, Vanderbilt University

Study Description

Brief Summary:

This study is to determine different chemical levels in the blood during a low salt diet. This study will compare normal volunteers to those with Postural Tachycardia Syndrome (POTS)

Condition or disease	Intervention/treatment	Phase
Postural Tachycardia Syndrome	Drug: Cosyntropin administration	Not Applicable

Detailed Description:

Patients with postural tachycardia syndrome had a subnormal increment in aldosterone with upright posture, which might reflect a blunted adrenal response to stimulation upon assuming upright posture. In this AIM, we propose to assess the adrenal response to aldosterone stimulation with intravenous adrenocorticotropin hormone.

For this protocol, subjects enrolled in the parent study will be approached about this sub-study. Subjects will be assured that they are not required to participate in this study even if they choose to participate in the parent study.

There will be no randomization for this specific sub-study. The order of diets (low sodium vs. high sodium) will be performed as a part of the parent study, and not as a part of this sub-study. This sub-study will only be performed in the LOW dietary salt phase.

All subjects will be previously screened and evaluated as a part of the parent study. No further screening will be performed exclusively for this study. Women of childbearing potential will have had a serum pregnancy test as a part of the parent study. Pregnant women will not be allowed to participate.

Study Design

• Study Type: Interventional (Clinical Trial)
• Estimated Enrollment: 50 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Other
• Official Title: Aldosterone and Sodium Regulation in Postural Tachycardia Syndrome Participating in the Dietary Salt in Orthostatic Tachycardia Study.
• Study Start Date: January 2013
• Actual Primary Completion Date: December 2020
• Estimated Study Completion Date: December 2021

Arms and Interventions

Arm	Intervention/treatment
Experimental: Low Salt Diet; Each participant will be asked to sit in a chair for 30 minutes prior to a blood draw. Then a small dose of cosyntropin is administered intravenous. Blood samples will be drawn again at 30 minutes and 60 minutes after the drug has been given.	Drug: Cosyntropin administration; After 30 minutes of rest in the seated position, participants will be given cosyntropin intravenously. Blood samples will be taken 30 minutes pre-drug administration, 30 minutes post and 60 minutes post drug administration.; Other Name: Cortrosyn

Outcome Measures

Primary Outcome Measures :

1. Adrenal responsiveness to adrenocorticotropin hormone. (ACTH) [ Time Frame: 24 hours ]
   To assess the adrenal responsiveness to adrenocorticotropin hormone (ACTH), as measured by plasma aldosterone level, is contributing to the pathophysiology of Orthostatic Tachycardia.

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 50 Years (Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Criteria

Inclusion Criteria:

Subjects will be enrolled in the parent study "Dietary Salt in Postural Tachycardia Syndrome" during the "LOW SALT" phase

Postural Tachycardia Syndrome Diagnosed with postural tachycardia syndrome by the Vanderbilt Autonomic Dysfunction Center Increase in heart rate ≥30 beats/min with position change from supine to standing (10 minutes) Chronic symptoms consistent with POTS that are worse when upright and get better with recumbence

• Control Subjects

  • Healthy, non-obese, non-smokers without orthostatic tachycardia
  • Selected to match profiles of POTS patients (gender, age)
  • Not using vasoactive medication
• Age between 18-50 years
• Male and female subjects are eligible.
• Able and willing to provide informed consent

Exclusion Criteria:

• Overt cause for postural tachycardia (such as acute dehydration)
• Inability to give, or withdrawal of, informed consent
• pregnant
• Other factors which in the investigator's opinion would prevent the subject from completing the protocol.

Contacts and Locations

Locations

United States, Tennessee

Vanderbilt University Medical Center

Nashville, Tennessee, United States, 37232

Sponsors and Collaborators

Vanderbilt University

National Institutes of Health (NIH)

National Heart, Lung, and Blood Institute (NHLBI)

Investigators

• Principal Investigator: Alfredo J Gamboa, MD; Vanderbilt University Medical Center

More Information

• Responsible Party: Alfredo Gamboa, Research Associate Professor of Medicine, Vanderbilt University
• ClinicalTrials.gov Identifier: NCT01764711
• Other Study ID Numbers: 120612; R01HL102387 ( U.S. NIH Grant/Contract )
• First Posted: January 9, 2013
• Last Update Posted: May 3, 2021
• Last Verified: April 2021

Keywords provided by Alfredo Gamboa, Vanderbilt University:

POTS

Additional relevant MeSH terms:

Postural Orthostatic Tachycardia Syndrome; Tachycardia; Syndrome; Disease; Pathologic Processes; Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Cardiac Conduction System Disease; Orthostatic Intolerance; Primary Dysautonomias; Autonomic Nervous System Diseases; Nervous System Diseases; Cosyntropin; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists; Physiological Effects of Drugs