Yeh Rong-Guan, Shieh Jiann-Shing, Chen Gau-Yang, Kuo Cheng-Deng
Institute of Mechanical Engineering, Yuan Ze University, Tao-Yuan, Taiwan.
Auton Neurosci. 2009 Oct 5;150(1-2):122-6. doi: 10.1016/j.autneu.2009.05.241. Epub 2009 May 22.
Spectral analysis of heart rate variability using short or long time series is a common method in the assessment of autonomic nervous activity. Nonlinear method such as detrended fluctuation analysis was proposed and proved to be useful for the possible non-stationary and nonlinear characteristics in the time series of heart period. In this study, we investigated the detrended fluctuation analysis and conventional heart rate variability measures in 16 late pregnant women before and 3 months after delivery and in 16 healthy controls. Global and discrete, short-term (< or =11 beats, alpha1) and long-term (>11 beats, alpha2), scaling exponent were calculated in detrended fluctuation analysis. We found that the late pregnant women have elevated global scaling exponent, elevated short-term scaling exponent and lower heart rate variability measures in the low and high frequency ranges than those of the healthy controls and 3 months after delivery. The deranged measures recovered 3 months after delivery. In addition, the detrended fluctuation scaling exponent did not correlate with most conventional time and frequency domain measures of heart rate variability. Our study suggested that the global and short-term detrended fluctuation scaling exponents might be new and independent measures of heart rate variability in late pregnancy, in addition to those conventional time and frequency domain measures.
使用短时间序列或长时间序列对心率变异性进行频谱分析是评估自主神经活动的常用方法。诸如去趋势波动分析等非线性方法被提出，并被证明对心动周期时间序列中可能存在的非平稳和非线性特征有用。在本研究中，我们调查了16名晚期孕妇在分娩前和分娩后3个月以及16名健康对照者的去趋势波动分析和传统心率变异性测量。在去趋势波动分析中计算了全局和离散的、短期（≤11次搏动，α1）和长期（>11次搏动，α2）标度指数。我们发现，晚期孕妇的全局标度指数升高、短期标度指数升高，且低频和高频范围内的心率变异性测量值低于健康对照者和分娩后3个月时的测量值。这些紊乱的测量值在分娩后3个月恢复。此外，去趋势波动标度指数与大多数传统的心率变异性时域和频域测量值不相关。我们的研究表明，除了那些传统的时域和频域测量值外，全局和短期去趋势波动标度指数可能是晚期妊娠中心率变异性新的独立测量指标。
