Lee J M, Park K S, Hwang J H, Park M I, Yum M K
Dept. of Biomedical Engineering, Seoul National University School of Medicine, Korea.
Early Hum Dev. 1998 Dec;53(2):121-8. doi: 10.1016/s0378-3782(98)00046-2.
We studied how chaotic and periodic heart rate dynamics differ between normal fetuses (n = 192) and uncomplicated intrauterine growth restricted fetuses (n = 86), aged 31-42 weeks of gestation. We analyzed each fetal heart rate time series for 25 min. We quantified the chaotic dynamics of each fetal heart rate time series by correlation dimension. The periodic dynamics were analyzed by power spectral analysis. The correlation dimension and, therefore, the complexity, of the heart rate dynamics of the uncomplicated intrauterine growth restricted fetuses was significantly lower than that of the normal fetuses, which was marked at 38-42 weeks of gestation. The low-frequency (0.04-0.15 Hz) component and, therefore, the periodicity of the low-frequency range was significantly higher than that of the normal fetuses during all the gestational weeks. These results mean that, although the intrauterine growth restricted fetuses are not severely compromised, the overall integrity of their cardiovascular control is impaired, especially at term; and sympathetic modulation is increased, both of which may contribute to increased perinatal mortality.
我们研究了妊娠31 - 42周的正常胎儿（n = 192）和无并发症的宫内生长受限胎儿（n = 86）的心率动力学中混沌和周期性的差异。我们对每个胎儿心率时间序列进行了25分钟的分析。我们通过关联维数对每个胎儿心率时间序列的混沌动力学进行了量化。通过功率谱分析对周期性动力学进行了分析。无并发症的宫内生长受限胎儿心率动力学的关联维数以及复杂度显著低于正常胎儿，这种差异在妊娠38 - 42周时尤为明显。在所有孕周中，宫内生长受限胎儿的低频（0.04 - 0.15 Hz）成分以及低频范围的周期性显著高于正常胎儿。这些结果意味着，尽管宫内生长受限胎儿并未受到严重损害，但其心血管控制的整体完整性受损，尤其是在足月时；并且交感神经调节增强，这两者都可能导致围产期死亡率增加。
