Pagani M, Montano N, Porta A, Malliani A, Abboud F M, Birkett C, Somers V K
Centro Ricerche Cardiovascolari, CNR, Medicina Interna II, Ospedale L. Sacco, Università di Milano, Italy.
Circulation. 1997 Mar 18;95(6):1441-8. doi: 10.1161/01.cir.95.6.1441.
Spectral analysis of RR interval and systolic arterial pressure variabilities may provide indirect markers of the balance between sympathetic and vagal cardiovascular control.
We examined the relationship between power spectral measurements of variabilities in RR interval, systolic arterial pressure, and muscle sympathetic nerve activity (MSNA) obtained by microneurography over a range of blood pressures. In eight healthy human volunteers, MSNA, RR interval, intra-arterial pressure, and respiration were measured during blood pressure reductions induced by nitroprusside and during blood pressure increases induced by phenylephrine. Both low-frequency (LF; 0.10 +/- 0.01 Hz) and high-frequency (HF; 0.23 +/- 0.01 Hz) components were detected in MSNA variability. Increasing levels of MSNA were associated with a shift of the spectral power toward its LF component. Decreasing levels of MSNA were associated with a shift of MSNA spectral power toward the HF component. Over the range of pressure changes, the LF component of MSNA variability was positively and tightly correlated with LF components of RR interval (in normalized units; P < 10(-6)) and of systolic arterial pressure variability (both in millimeters of mercury squared and normalized units; P < 5 x 10(-5) and P < 5 x 10(-6), respectively). The HF component of MSNA variability was positively and tightly correlated with the HF component (in normalized units) of RR-interval variability (P < 3 x 10(-4)) and of systolic arterial pressure variability (P < .01).
During sympathetic activation in normal humans, there is a predominance in the LF oscillation of blood pressure, RR interval, and sympathetic nerve activity. During sympathetic inhibition, the HF component of cardiovascular variability predominates. This relationship is best seen when power spectral components are normalized for total power. Synchronous changes in the LF and HF rhythms of both RR interval and MSNA during different levels of sympathetic drive are suggestive of common central mechanisms governing both parasympathetic and sympathetic cardiovascular modulation.
RR间期和收缩期动脉压变异性的频谱分析可能提供交感神经和迷走神经心血管控制平衡的间接标志物。
我们研究了通过微神经ography在一系列血压范围内获得的RR间期、收缩期动脉压和肌肉交感神经活动（MSNA）变异性的功率谱测量值之间的关系。在8名健康人类志愿者中，在硝普钠诱导的血压降低期间和去氧肾上腺素诱导的血压升高期间测量了MSNA、RR间期、动脉内压和呼吸。在MSNA变异性中检测到低频（LF；0.10±0.01Hz）和高频（HF；0.23±0.01Hz）成分。MSNA水平升高与频谱功率向其LF成分的转移相关。MSNA水平降低与MSNA频谱功率向HF成分的转移相关。在压力变化范围内，MSNA变异性的LF成分与RR间期的LF成分（以标准化单位；P<10^(-6)）和收缩期动脉压变异性的LF成分（以毫米汞柱平方和标准化单位；分别为P<5×10^(-5)和P<5×10^(-6)）呈正相关且紧密相关。MSNA变异性的HF成分与RR间期变异性的HF成分（以标准化单位）（P<3×10^(-4)）和收缩期动脉压变异性的HF成分（P<0.01）呈正相关且紧密相关。
在正常人类交感神经激活期间，血压、RR间期和交感神经活动的LF振荡占主导。在交感神经抑制期间，心血管变异性的HF成分占主导。当功率谱成分针对总功率进行标准化时，这种关系最为明显。在不同水平的交感神经驱动下，RR间期和MSNA的LF和HF节律的同步变化提示了共同的中枢机制控制副交感神经和交感神经心血管调节。
