About this trial
Autonomic nervous system imbalance causes postural tachycardia and related cardiac symptoms in Postural Orthostatic Tachycardia Syndrome (POTS). The impact of POTS is more far-reaching than postural tachycardia. Several systemic, autonomic symptoms along with neuro-cognitive dysfunction leading to poor quality of life contribute to significant disability in POTS. A combination of abnormal autonomic tone, abnormal cerebral blood flow regulation, and systemic inflammation may contribute to POTS symptoms.
Auricular Vagal Neuromodulation Therapy (aVNT) has the potential for multisystem holistic benefit for patients with POTS: Autonomic neuromodulation by aVNT might address multiple aspects of POTS pathophysiology and improve POTS symptoms. It can reduce postural tachycardia by increasing the parasympathetic (PNS) and decreasing sympathetic (SNS) tone. In patients undergoing vagus nerve stimulation for various indications, an increase in PNS tone has been associated with improved middle cerebral artery velocity (MCAv) at rest and during cognitive stress. aVNT has been associated with improved cerebral blood flow and reduced infarct size in an experimental model of ischemic stroke, suggesting similar improvements in cerebral autoregulation in POTS. Vagus nerve stimulation has also been linked to improved cognitive function. The anti-inflammatory effect and improved endothelial function might improve cerebral blood flow regulation and cognitive function. The anti-inflammatory effects of aVNT may improve postural hemodynamics, reduce postural tachycardia, relieve other POTS symptoms, and improve quality of life (QoL). POTS is a complex multisystem disorder with debilitating symptoms that currently lack effective treatments. aVNT has the potential to recalibrate autonomic tone dysregulation, enhance MCAv, improve cognitive function, reduce inflammation, and ultimately improve symptoms and quality of life in POTS patients.
Eligibility criteria
Qualifiers
POTS Patients: POTS patients will meet Canadian Cardiovascular Society criteria. 6 POTS patients will have orthostatic tachycardia >30 bpm increase in HR within 10 minutes of upright posture [>40 bpm in patients <20 years]), in the absence of orthostatic hypotension (drop in BP >20/10 mmHg), chronic symptoms of orthostatic intolerance, and no obvious cause for the tachycardia.
Age between 18-80 years
Male and female subjects are eligible
Able and willing to provide informed consent
Disqualifiers
Unable to give informed consent
Stimulant use within one week of the study
Systolic blood pressure >150 mm Hg and/or diastolic blood pressure > 100 mm Hg
Neurogenic orthostatic hypotension, prior stroke, myocardial infarction or heart failure, hematocrit < 28%
Trial design
Treatments tested in this trial
- active aVNT vs. Sham