Department of Electronics, Information, and Bioengineering, Politecnico di Milano, 20133 Milan, Italy.
IRCCS Fondazione Don Carlo Gnocchi ONLUS, 20148 Milan, Italy.
Biosensors (Basel). 2022 Jun 15;12(6):417. doi: 10.3390/bios12060417.
Beat-by-beat variability (BBV) rhythms are observed in both cardiovascular (CV) and intracranial (IC) compartments, yet interactions between the two are not fully understood. Real-Time Phase-Contrast (RT-PC) MRI sequence was acquired for 30 healthy volunteers at 1st cervical level on a 3T scanner. The arterial (AF), venous (VF), and cerebrospinal fluid (CSF) flow (CSFF) were computed as velocity integrals over the internal carotid artery, internal jugular vein, and CSF. AF, VF, and CSFF signals were segmented in inspiration and expiration beats, to assess the respiration influence. Systolic and diastolic BBV, and heart period series underwent autoregressive power spectral density analysis, to evaluate the low-frequency (LF, Mayer waves) and high frequency (HF, respiratory waves) components. The diastolic VF had the largest BBV. LF power was high in the diastolic AF series, poor in all CSFF series. The pulse wave analyses revealed higher mean amplitude during inspiration. Findings suggests a possible role of LF modulation of IC resistances and propagation of HF waves from VF to AF and CCSF. PC-RT-MRI could provide new insight into the interaction between CV and IC regulation and pave the way for a detailed analysis of the cerebrovascular effects of varied respiration patterns due to exercise and rehabilitation.
在心血管（CV）和颅内（IC）腔室中都观察到逐拍变异性（BBV）节律，但两者之间的相互作用尚不完全清楚。在 3T 扫描仪上对 30 名健康志愿者的第 1 颈椎水平进行了实时相位对比（RT-PC）MRI 序列采集。动脉（AF）、静脉（VF）和脑脊液（CSF）流量（CSFF）被计算为颈内动脉、颈内静脉和 CSF 的速度积分。对吸气和呼气搏动进行分段，以评估呼吸的影响。评估低频（LF，Mayer 波）和高频（HF，呼吸波）成分，对收缩期和舒张期 BBV 和心动周期系列进行自回归功率谱密度分析。舒张期 VF 的 BBV 最大。舒张期 AF 系列中的 LF 功率较高，所有 CSFF 系列中的 LF 功率均较差。脉搏波分析显示吸气时平均振幅较高。研究结果表明，LF 对 IC 阻力的调制和 HF 波从 VF 到 AF 和 CCSF 的传播可能起作用。PC-RT-MRI 可以为 CV 和 IC 调节之间的相互作用提供新的见解，并为由于运动和康复引起的不同呼吸模式对脑血管影响的详细分析铺平道路。
