Breathing Device in Postural Orthostatic Tachycardia Syndrome (POTS)

Study Overview
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Brief Summary
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The investigators will test whether breathing through an inspiratory resistance device will improve the ability to be upright and decrease heart rate increases on standing in patients with postural tachycardia syndrome.

Detailed Description
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Chronic orthostatic intolerance, sometimes known as the postural tachycardia syndrome (POTS), is the most common disorder among patients seen at several centers specializing in diseases of the autonomic nervous system. It affects an estimated 500,000 people in the United States alone. POTS (excessive increase in heart rate [>30 min-1] on standing associated with orthostatic symptoms [including palpitation, chest pain syndrome, dyspnea on standing, mental clouding and difficulties with concentration], in the absence of orthostatic hypotension) can produce substantial disability among otherwise healthy people. Patients with POTS typically feel tired and run down. Many also report a myriad of symptoms that are hard to categorize, often involving fatigue. One study, from the Mayo Clinic, found that patients with POTS had a diminished quality of life when measured using a standard health status instrument (SF-36). In this pilot study, we will test the hypothesis that breathing through an inspiratory resistance device will improve orthostatic tolerance and reduce orthostatic tachycardia in patients with postural tachycardia syndrome.

Official Title
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Assessment of Inspiratory Breathing Devices to Improve Orthostatic Tolerance in Postural Orthostatic Tachycardia Syndrome

Conditions
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Postural Tachycardia Syndrome, Postural Orthostatic Tachycardia Syndrome

Intervention / Treatment
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* Device: Inspiratory Threshold Device (Res-Q-Gard ITD)
* Device: Sham Inspiratory Threshold Device


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 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 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

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ITD breathing device<br>Breathing through the Res-Q-Gard ITD device from Advanced Circulatory Systems Inc. | Device: Inspiratory Threshold Device (Res-Q-Gard ITD)<br>* Patient will breathe through this device attached to a mouthpiece during assessment of orthostatic tolerance.<br>* Other names: Res-Q-Gard ITD device 7.0 (Ref:12-0463-000);|
| Sham Comparator: Sham Device<br>Breathing through a respiratory particulate filter (Model 002850P, Sims Portex Inc, Keene NH) which will have minimal resistance. | Device: Sham Inspiratory Threshold Device<br>* Breathing through a respiratory particulate filter (Model 002850P, Sims Portex Inc, Keene NH) which will have minimal resistance.<br>* Other names: Model 002850P, Sims Portex Inc, Keene NH;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Magnitude of orthostatic heart rate increase on upright posture |  | 10 min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Symptoms rating with upright posture |  | 10 min | 
| Hemodynamic changes on upright posture |  | 10 min | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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heart rate, tachycardia, orthostatic intolerance