A "dysautonomic" head-up tilt test pattern in elderly patients with neurocardiogenic syncope

The characteristics of neurocardiogenic syncope (NCS) in elderly patients r emain unclear. We compared the hemodynamic profiles of young and older pati ents with consecutive and positive head-up tilt tests (HUT). Continuous, no ninvasive, and reliable monitoring of arterial pressure (AP) and heart rate (HR) was done throughout 46 consecutive positive HUTs of symptomatic patie nts. The population (12-82 years old) was divided into two groups: younger patients, Y (n = 25 less than or equal to 65 years), and older patients, O (n = 21). Changes in AP and HR after the first minute of tilting, during th e stable orthostatic phase and during syncope were compared. Except for sys tolic pressure, baseline hemodynamic parameters were similar in Y and O. No difference appeared in the mean time elapsed before syncope (19 +/- 9 vs 2 2 +/- 2 min). Asymptomatic hypotension was observed, only in O, 1 minute af ter tilting, followed by a progressive fall in the mean AP before syncope ( 0 +/- 0.9 vs -1 +/- 0.7 mmHg/min) without HR increase (0.7 +/- 2 vs 0 +/- 0 .6 beats/min). This pressure slope was strongly related to age (r = 0.54, P < 0.001). Hemodynamic recording during HUT identifies a dysautonomic patte rn in elderly patients with NCS and the abnormal AP/HR responses to orthost asis may be a feature specific to this population. Although the central mec hanism of NCS is common to all ages, the age-related characteristics of the trigger event may indicate the need for specific management at different a ges.