The purpose of this study is to describe the mechanism of orthostatic intolerance, relying on cardiovascular physiological studies. The syndrome is of undetermined etiology, but the syndrome causes impairment of a number of young adults, females more than males, with symptoms of tachycardia, fatigue, lightheadedness, palpitations, blurred vision, chest discomfort, difficulty concentrating, and dizziness with the upright posture. It is believed that many different pathophysiological processes can give rise to this disorder.
The purpose of this study is to describe the mechanism of orthostatic intolerance, relying on cardiovascular physiological studies. The syndrome is of undetermined etiology, but the syndrome causes impairment of a number of young adults, females more than males, with symptoms of tachycardia, fatigue, lightheadedness, palpitations, blurred vision, chest discomfort, difficulty concentrating, and dizziness with the upright posture. It is believed that many different pathophysiological processes can give rise to this disorder. This is not a clinical trial in the classical sense, but an omnibus protocol to allow for disntinct and personalized pathophysiological testing.
Study Type
INTERVENTIONAL
Allocation
NON_RANDOMIZED
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
260
Vanderbilt University
Nashville, Tennessee, United States
Physiological abnormalities in orthostatic intolerance
varied metrics used here
Time frame: 1 day
blood volume
Blood volume as measured by DAXOR technique
Time frame: 1 day
intrinsic heart rate
Heart rate after IV propranolol and IV atropine
Time frame: 1 hour
quantitative sweat testing
sweat volumes after a QSweat test
Time frame: 2 hours
residual sympathetic function after pharmacological autonomic blockade
changes in BP after trimethaphan infusions
Time frame: 3 hours
norepinephrine spillover
tritiated norepunephrine spillover data
Time frame: 3 hours
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.