CRI in POTS in Adolescents

Autonomic dysfunction (or dysautonomia) describes several medical conditions linked to the autonomic nervous system. One of these is Postural Orthostatic Tachycardia Syndrome (POTS). In pediatric populations, symptoms of autonomic dysfunction include an increase in heart rate when standing up (tachycardia), dizziness, nausea, vomiting, fatigue, headaches, abdominal discomfort, and sleep disturbances. POTS is specifically characterized by orthostatic intolerance and a forty beats per minute (bpm) increase in heart rate upon standing. The etiology of POTS is poorly understood, and there is limited literature on the management of POTS in pediatric populations. In the U.S., POTS is estimated to affect 1-3 million people. The ability of the CRI algorithm to accurately distinguish individuals with varying tolerances to reduced central blood volume can be attributed to a unique function of the algorithm, which analyzes and compares the entirety of each waveform in a window of time to trend subtle features that correspond with varying degrees of central volume loss. CRI can also detect vascular changes associated with postural orthostatic tachycardia syndrome. CRI will be evaluated in subjects at supine and standing positions along with traditional orthostatic measures. Following CRI measurements, subjects and their parents will be asked to complete a series of surveys to assess their psychosocial symptoms and functional impairment. The CRI measurement and survey completion will occur over the course of one clinic visit.