Højgaard M V, Holstein-Rathlou N H, Agner E, Kanters J K
Department of Internal Medicine, Coronary Care Unit, Elsinore Hospital, DK-3400 Elsinore, Denmark.
Am J Physiol. 1998 Jul;275(1):H213-9. doi: 10.1152/ajpheart.1998.275.1.H213.
Frequency domain analysis of heart rate variability (HRV) has been proposed as a semiquantitative method for assessing activities in the autonomic nervous system. We examined whether absolute powers, normalized powers, and the low frequency-to-high frequency ratio (LF/HF) derived from the HRV power spectrum could detect shifts in autonomic balance in a setting with low sympathetic nervous tone. Healthy subjects were examined for 3 h in the supine position during 1) control conditions (n = 12), 2) acute beta-blockade (n = 11), and 3) chronic beta-blockade (n = 10). Heart rate fell during the first 40 min of the control session (72 +/- 2 to 64 +/- 2 beats/min; P < 0. 005) and was even lower during acute and chronic beta-blockade (56 +/- 2 beats/min; P < 0.005). The powers of all spectral areas rose during the first 60 min in all three settings, more so with beta-blockade (P < 0.05). LF/HF was found to contain the same information as powers expressed in normalized units. LF/HF detected the shift in autonomic balance induced by beta-blockade but not the change induced by supine position. In conclusion, none of the investigated measures derived from power spectral analysis comprehensively and consistently described the changes in autonomic balance.
心率变异性（HRV）的频域分析已被提议作为一种评估自主神经系统活动的半定量方法。我们研究了从HRV功率谱得出的绝对功率、标准化功率以及低频与高频比值（LF/HF）是否能在交感神经张力较低的情况下检测到自主平衡的变化。对健康受试者在仰卧位进行3小时检查，期间分为：1）对照条件（n = 12）；2）急性β受体阻滞剂治疗（n = 11）；3）慢性β受体阻滞剂治疗（n = 10）。在对照期的前40分钟心率下降（从72±2降至64±2次/分钟；P < 0.005），在急性和慢性β受体阻滞剂治疗期间心率更低（56±2次/分钟；P < 0.005）。在所有三种情况下，所有频谱区域的功率在最初60分钟内均升高，β受体阻滞剂治疗时升高更明显（P < 0.05）。发现LF/HF与以标准化单位表示的功率包含相同信息。LF/HF检测到了β受体阻滞剂引起的自主平衡变化，但未检测到仰卧位引起的变化。总之，从功率谱分析得出的所有研究指标均未全面且一致地描述自主平衡的变化。
