Search

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. [ABSTRACT FROM AUTHOR]

Objective To investigate the diagnostic value of transcranial Doppler (TCD) combined with headup tilt test (HUTT) in patients with orthostatic cerebral hypoperfusion syndrome (OCHOs). Methods We selected the patients going to hospital due to syncope or suspected orthostatic intolerance, and their etiology was considered as OCHOs. Cerebral blood flow parameters and hemodynamic parameters of patients were collected separately by TCD and HUTT, and healthy control group was set up. TCD cerebral blood flow parameters and HUTT hemodynamic parameters were compared between the OCHOs patients and the control group. Results A total of 56 OCHOs patients (case group) and 21 healthy adults in the control group are enrolled. In terms of TCD cerebral blood flow parameters, compared with the supine position, the absolute values of the decrease of systolic, enddiastolic and mean cerebral blood flow velocity in the case group are significantly higher than those in the control group during the tilt upright position; the absolute values of the increase of pulse index and circulation resistance index are also significantly higher than those in the control group (P < 0. 01). There is no significant difference in HUTT hemodynamic parameters between the two groups (P > 0. 05). The receiver operator characteristic curve is drawn. Compared with the supine position, systolic, end-diastolic and mean cerebral blood flow velocity in the case group decrease by 14. 5, 9. 5 and 13. 5 cm / s, respectively during the tilt upright position. Their sensitivity is separately 94. 6%, 87. 5% and 91. 1% while the specificity is separately 95. 2%, 85. 7% and 95. 2% in diagnosing OCHOs (P < 0. 01). Conclusion TCD combined with HUTT plays an important role in diagnosing OCHOs. [ABSTRACT FROM AUTHOR]