Abstract：Objective To investigate the hemodynamic parameter characteristics of patients with neurogenic orthostatic hypotension (nOH) in the head-up tilt test (HUTT). Methods Patients diagnosed with typical nOH in the syncope clinic of our hospital were selected. Hemodynamic parameters of these patients during HUTT including systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, stroke volume, cardiac output and systemic vascular resistance in the supine and tilted upright positions were collected, and retrospectively analyzed. The patients were divided into two groups according to age (age≥60 years group with 46 patients and age<60 years group with 36 patients ). The characteristics of the above hemodynamic parameters were compared between the two groups in the supine position, and at the 1st, 2nd, and 3rd minute in tilted upright position. Results For all patients, systemic vascular resistance does not increase from the supine to the tilted upright position. The increase of heart rate, the decrease of stroke volume and their degree of variability from the supine to the titled upright position are significantly lower in patients≥60 years than those in patients <60 years. Conclusion In patients with typical nOH, the increase of systemic vascular resistance from the supine position to the tilted upright position is impaired. Among these patients <60 years, heart rate increases and stroke volume decreases significantly in the tilted upright position.
