Periaqueductal Gray-vagus Nerve Interface Malfunction Explain the Natural History With Its Numerous Co-morbidities?

Study Overview
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Brief Summary
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This study is being conducted to see how people with Postural tachycardia syndrome (POTS) make sense of the things they see. The information may help doctors to learn more about how the different parts of people's brains communicate.

Official Title
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Pediatric POTS: Does a Periaqueductal Gray-vagus Nerve Interface Malfunction Explain the Natural History With Its Numerous Co-morbidities?

Conditions
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Postural Tachycardia Syndrome

Intervention / Treatment
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* Behavioral: Looming task


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Females 12-21 years old Able to communicate and provide consent/assent English speaking Diagnosed with POTS (POTS will be defined standardly as a symptomatic ≥ 40 bpm rise in heart rate without a drop in blood pressure and with symptoms of orthostatic intolerance clinically) Age-matched healthy control subjects: no POTS or other neurological disorders Exclusion Criteria: Inflammatory arthritis, connective tissue or auto-immune disorder Any chronic neurological disorder besides POTS Evidence of unstable medical disorder, such as kidney (rising creatinine, or end-stage renal failure) or liver impairment (rising AST or ALT, or end-stage with coagulopathy), poorly controlled significant cardiovascular (CHF), respiratory, endocrine (diabetes - A1c > 9 - or untreated thyroid dysfunction) or uncontrolled psychiatric illness (such as untreated depression, psychosis, etc.) Neuropathy, central nervous system disorder (e.g., Cerebral palsy, developmental delay, seizure disorder, MS, stroke, etc.) Treatment with a drug or medical device within the previous 30 days that has not received regulatory approval Use of hormones (except insulin, thyroid replacement or oral contraceptives, which will be carefully documented) Current substance or alcohol abuse Any major surgical intervention with general anesthesia in the last 60 days and minor procedure, such as tooth extraction, endoscopy, etc., with local or conscious sedation within 7 days Any on-going or pending medical, health or disability related litigation, or current pursuit of disability Any condition that in the judgment of the investigator would interfere with the patient's ability to provide informed consent, comply with study instructions, place the patient at increased risk, or which would clearly confound the interpretation of the study results (specific reason will be documented) Chronic use of narcotics for pain Claustrophobia or any metal hardware that may interfere with MRI Investigators and study staff

Ages Eligible for Study
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Minimum Age: 12 Years
Maximum Age: 21 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Adolescents with POTS<br> | Behavioral: Looming task<br>* Participants will be asked to look at some pictures during an fMRI scan. Participants will press a button as soon as they see the image appear.<br>|
| Other: Adolescents without POTS<br> | Behavioral: Looming task<br>* Participants will be asked to look at some pictures during an fMRI scan. Participants will press a button as soon as they see the image appear.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Periaqueductal gray region activation - looming task | Functional magnetic resonance imaging (fMRI) will be performed to measure activation of the periaqueductal gray region during the looming task | 90 minutes | 
| Periaqueductal gray region activation - resting | Functional magnetic resonance imaging (fMRI) will be performed to measure activation of the periaqueductal gray region while at rest | 90 minutes |