Differences in neurohumoral and hemodynamic response to prolonged head-up tilt between patients with high and normal standing norepinephrine forms of postural orthostatic tachycardia syndrome

One blood sample taken at the 10th minute of HUT correctly identifies high and normal standing NE POTS patients, but a small number of patients (1 out of 19, 5.2%) can be misidentified. High and normal standing NE POTS patients display distinctly different neurohumoral and hemodynamic responses to HUT.