Baumert J H, Frey A W, Adt M
Institut für Anästhesiologie, Deutsches Herzzentrum Berlin.
Anaesthesist. 1995 Oct;44(10):677-86. doi: 10.1007/s001010050201.
BACKGROUND AND METHODS. Small, periodic fluctuations in heart rate are well known to physicians, the respiratory sinus arrhythmia (RSA) being the most easily detectable form of this heart rate variability (HRV). Since it is caused by changing activity of the autonomic nervous system (ANS) controlling heart rate, HRV is investigated to gain information on the functional states of the ANS. Recent developments have led to computer-aided processing of EKG signals based on time and frequency domain methods--the latter using power spectral analysis by fast Fourier or autoregressive algorithms--to exactly describe and quantify HRV. Three major regions in the frequency spectrum between 0.03 and 0.5 Hz (the suitable range for shortterm recordings) have been established: (1) a region around the respiratory rate, usually between 0.2 and 0.35 Hz, called high frequency (HF), (2) a region around 0.1 Hz attributed to vasomotor activity feedback, called low (or mid-) frequency (LF), (3) a peak around 0.04-0.05 Hz correlated to thermoregulation, called very low (or low)frequency (VLF). Power spectral density of HRV is now commonly accepted as a measure of autonomic cardiovascular control activity. By studies on vagal or sympathetic blockade, the HF (or RSA) region has been attributed solely to vagal activity, while both parts of the ANS may contribute to the other two, with, however, the vagal part predominating the resting, healthy individuals. CLINICAL APPLICATIONS/ANAESTHESIA. Thus, spectral analysis of HRV provides a measure for quantifying sympatho-vagal balance in its physiological range. Additionally, reduction of HRV along with cardiovascular disease, including hypertension, myocardial infarction, heart failure and sudden cardiac death, as well as with autonomic dysregulation, has been reported. Since is also a striking reduction produced by most anaesthetic agents, RSA and HRV are investigated as measures of anaesthetic depth. There are contradictory data on the influence of ventilation, medication, and co-existing disease on the spectrum, and thus validation of the method is still to be achieved. It has, however, been proven useful in some studies as a parameter for risk assessment of perioperative or post-infarction cardiovascular complications.
背景与方法。医生们熟知心率存在微小的周期性波动，其中呼吸性窦性心律不齐（RSA）是这种心率变异性（HRV）最易于检测到的形式。由于它是由控制心率的自主神经系统（ANS）活动变化引起的，因此对HRV进行研究以获取有关ANS功能状态的信息。最近的进展已实现基于时域和频域方法对心电图信号进行计算机辅助处理——频域方法使用快速傅里叶或自回归算法进行功率谱分析——以精确描述和量化HRV。在0.03至0.5赫兹之间的频谱（适用于短期记录的范围）已确定三个主要区域：（1）呼吸频率附近的区域，通常在0.2至0.35赫兹之间，称为高频（HF）；（2）约0.1赫兹附近归因于血管运动活动反馈的区域，称为低频（或中频）（LF）；（3）约0.04 - 0.05赫兹处与体温调节相关的峰值，称为极低频（或低频）（VLF）。HRV的功率谱密度现在通常被视为自主心血管控制活动的一种度量。通过对迷走神经或交感神经阻滞的研究，HF（或RSA）区域仅归因于迷走神经活动，而ANS的两个部分可能对另外两个区域都有贡献，不过在静息的健康个体中迷走神经部分占主导。临床应用/麻醉。因此，HRV的频谱分析提供了一种在其生理范围内量化交感 - 迷走平衡的方法。此外，已有报道称HRV会随着心血管疾病（包括高血压、心肌梗死、心力衰竭和心源性猝死）以及自主神经调节异常而降低。由于大多数麻醉剂也会使其显著降低，因此对RSA和HRV进行研究以作为麻醉深度的指标。关于通气、药物和并存疾病对频谱的影响存在相互矛盾的数据，因此该方法仍有待验证。然而，在一些研究中已证明它作为围手术期或心肌梗死后心血管并发症风险评估的参数是有用的。
