Voss A, Malberg H, Schumann A, Wessel N, Walther T, Stepan H, Faber R
University of Applied Sciences, Jena, Germany.
Am J Hypertens. 2000 Nov;13(11):1218-25. doi: 10.1016/s0895-7061(00)01199-7.
Heart rate variability is a relevant predictor of cardiovascular risk in humans. However, to use heart and blood pressure (BP) variability or baroreflex sensitivity as markers for hypertensive pregnancy disorders, it is first necessary to describe these parameters in normal pregnancy. To accommodate the complexities of autonomic cardiovascular control we added parameter domains of nonlinear dynamics to conventional linear methods of time and frequency domains. The BP of 27 women with normal pregnancy and 14 nonpregnant women were monitored at a high resolution (200 Hz sampling frequency) using a Portapres for 30 min. The pregnant women were divided into groups of 32 or less or greater than 32 weeks of gestation. Pregnant and nonpregnant women were classified into subclasses of maternal age of less than 28 or 28 or more years. Except for two single parameter domains, we found no significant differences in heart rate and BP variability for pregnant women with different gestational age or different maternal age. Moreover, no significant differences in spontaneous baroreflex sensitivity could be found between pregnant women regardless of either their age or gestational age. In contrast, all measures of nonlinear dynamics of heart rate variability as well as all parameter domains of spontaneous baroreflex sensitivity showed significant changes between pregnant and nonpregnant women, whereas BP variability did not differ between those groups. This complex assessment of autonomic cardiovascular regulation has shown that the parameters tested are stable in the second half of normal pregnancy, and might have the potential to be excellent indicators of pathophysiologic conditions.
心率变异性是人类心血管风险的一个相关预测指标。然而，要将心率和血压（BP）变异性或压力反射敏感性用作妊娠高血压疾病的标志物，首先有必要描述正常妊娠中的这些参数。为了适应自主心血管控制的复杂性，我们在传统的时域和频域线性方法中增加了非线性动力学的参数域。使用Portapres以高分辨率（200Hz采样频率）对27名正常妊娠妇女和14名非妊娠妇女的血压进行30分钟监测。将孕妇分为妊娠32周及以下或大于32周的组。将孕妇和非孕妇按母亲年龄小于28岁或28岁及以上分为亚组。除了两个单参数域，我们发现不同孕周或不同母亲年龄的孕妇在心率和血压变异性方面没有显著差异。此外，无论孕妇年龄或孕周如何，自发压力反射敏感性均无显著差异。相比之下，心率变异性的所有非线性动力学测量以及自发压力反射敏感性的所有参数域在孕妇和非孕妇之间均显示出显著变化，而两组之间的血压变异性没有差异。这种对自主心血管调节的复杂评估表明，所测试的参数在正常妊娠后半期是稳定的，并且可能有潜力成为病理生理状况的优秀指标。
