心率变异性(heart rate variability,HRV)指连续正常心动周期的微小差异,是评估自主神经调节功能的重要指标。尽管HRV 的LF(low frequency)、HF(high frequency)、LF/HF等频域指标被广泛用于评估交感神经系统与副交感神经系统的活性及其两者的相互调节作用,然而它们作为衡量自主神经系统功能指标的有效性一直受到质疑。本研究剖析了有关LF、HF与LF/HF等频域指标意义的不同观点,探讨了其作为评估自主神经系统功能的合理性与有效性。本研究认 为,LF虽然受到交感神经活动的控制,但由于同时受迷走神经活动等其他因素的影响,且此影响程度较大,不建议单独使用LF以反映交感神经系统的活动;HF主要受心脏迷走神经的控制,能够较准确的反映迷走神经系统活动;LF/HF在一定程度上能够反映自主神经系统的调节作用,但由于存在非线性关系和其他因素的影响,LF/HF这一指标并不精准。

Heart rate variability (HRV) refers to small variations in consecutive normal cardiac cycles and is an important indicator of autonomic regulation. Although the frequency domain indices of HRV, such as low frequency (LF), high frequency (HF) and LF/HF, have been widely used to assess the activity of the sympathetic and parasympathetic nervous systems and their mutual regulation, their validity as indicators of autonomic nervous system function has been questioned. This study analyses the different views on the significance of LF, HF and LF/HF and examines their validity and effectiveness as indicators of autonomic nervous system function. In this study, it is proposed that LF, while influenced by sympathetic nerve activity, is not recommended for use alone to reflect sympathetic nerve activity, as it is also affected by other factors such as vagal nerve activity. HF, primarily controlled by cardiac vagal nerves, accurately reflects parasympathetic nervous system activity. LF/HF can reflect the regulatory role of the autonomic nervous system to a certain extent, but due to the non-linear relationship and the influence of other factors, the index of LF/HF is not precise.