Department of Neurology, Centro Hospitalar Universitário São João, Cardiovascular R&D Unit, Faculty of Medicine of University of Porto, Porto, Portugal.
Autonomic Unit, São João Hospital Center, Faculty of Medicine of University of Porto, Porto, Portugal.
Auton Neurosci. 2022 Nov;242:103010. doi: 10.1016/j.autneu.2022.103010. Epub 2022 Jul 11.
While there is strong evidence for autonomic involvement in cerebrovascular function acutely, long-term role of autonomic nervous system in cerebrovascular function has been controversial. We assessed autoregulation in 10 healthy individuals, nine patients with vasovagal syncope (VVS), and nine with Familial Amyloidotic Polyneuropathy (FAP), in response to head-up tilt test (HUTT).
Arterial blood pressure heart rate, cardiac output, and bilateral cerebral blood flow velocity (CBFV) at the M1 segment of middle cerebral artery (transcranial Doppler ultrasound) were recorded during supine rest and 70° HUTT. Autoregulation was quantified using a validated nonlinear and nonparametric approach based on projection pursuit regression. Plasma adrenaline and noradrenaline were also measured at rest and during HUTT.
During supine rest and HUTT, plasma noradrenaline content was lower in FAP patients. During HUTT, VVS patients had a hyperadrenergic status; CBFV decreased in all groups, which was greater in FAP patients (p < 0.01). Healthy controls responded to HUTT with a reduction in CBFV responses to increases (p = 0.01) and decreases (p < 0.01) in arterial pressure without any change in the range or effectiveness of autoregulation. VVS patients responded to HUTT with a reduction in falling (p = 0.02), but not rising slope (p = 0.40). Autoregulatory range (p < 0.01) and effectiveness increased (p = 0.09), consistent with the rapid increase in levels of catecholamines. In FAP patients, the level of increase in range of autoregulation was significantly related to the magnitude of increase in plasma noradrenaline in response to HUTT (R = 0.26, p = 0.05).
Autonomic dysfunction affects the cerebral autoregulatory response orthostatic to challenge.
虽然有强有力的证据表明自主神经系统在脑血管功能中具有急性作用，但自主神经系统在脑血管功能中的长期作用一直存在争议。我们评估了 10 名健康个体、9 名血管迷走性晕厥（VVS）患者和 9 名家族性淀粉样多发性神经病（FAP）患者在头高位倾斜试验（HUTT）中的自动调节功能。
在仰卧休息和 70°HUTT 期间，记录动脉血压、心率、心输出量和大脑中动脉 M1 段的双侧脑血流速度（经颅多普勒超声）。使用基于投影寻踪回归的验证后的非线性和非参数方法来量化自动调节。在休息和 HUTT 期间还测量了血浆肾上腺素和去甲肾上腺素。
在仰卧休息和 HUTT 期间，FAP 患者的血浆去甲肾上腺素含量较低。在 HUTT 期间，VVS 患者表现出高肾上腺素能状态；所有组的 CBFV 均下降，FAP 患者下降更明显（p<0.01）。健康对照组在 HUTT 时通过降低 CBFV 对动脉压升高（p=0.01）和降低（p<0.01）的反应来做出反应，而自动调节范围或有效性没有任何变化。VVS 患者在 HUTT 时对下降斜率（p=0.02）的反应降低，但对上升斜率（p=0.40）的反应没有降低。自动调节范围（p<0.01）和有效性增加（p=0.09），这与儿茶酚胺水平的快速增加一致。在 FAP 患者中，自动调节范围增加的程度与 HUTT 时血浆去甲肾上腺素增加的幅度显著相关（R=0.26，p=0.05）。
自主神经功能障碍影响对挑战的直立性脑自动调节反应。
