Boulos M, Barron S, Nicolski E, Markiewicz W
Department of Cardiology, Rambam Medical Center, Haifa, Israel.
Cardiology. 1996 Jan-Feb;87(1):28-32. doi: 10.1159/000177056.
We analyzed heart variability (HRV) response to tilt in 35 patients with a history of neurocardiogenic syncope and in 8 normal volunteers. Frequency domain examination was performed using power spectral analysis of RR variability during resting supine position and during the 256 beats preceding the onset of syncope or completion of 60 min of upright tilt to 70 degrees. Both low (0.05-0.15 Hz) and high frequency (0.15-0.4 Hz) spectral components of HRV increased markedly in all groups as a result of tilting. Statistically significant differences were noted between the patient groups at completion of upright tilting. However, these differences in spectral components between groups were of small magnitude when compared to the overall increase in spectral power occurring in all groups as a result of the tilt and are difficult to correlate clinically with the appearance, or lack of appearance of tilt-induced syncope. Power spectral analysis of HRV, as presently performed, appears to lack discriminative power to detect the rapid and marked changes in sympathovagal modulation known to occur during tilt test in patients with neurocardiogenic syncope.
我们分析了35例有神经心源性晕厥病史的患者及8名正常志愿者对倾斜试验的心率变异性（HRV）反应。在静息仰卧位以及晕厥发作前256次心跳期间或直立倾斜至70度60分钟结束时，通过对RR间期变异性进行功率谱分析来进行频域检查。由于倾斜，所有组的HRV低频（0.05 - 0.15Hz）和高频（0.15 - 0.4Hz）频谱成分均显著增加。直立倾斜结束时，患者组之间存在统计学显著差异。然而，与因倾斜导致的所有组频谱功率总体增加相比，组间频谱成分的这些差异幅度较小，且难以在临床上与倾斜诱发晕厥的出现或未出现相关联。目前所进行的HRV功率谱分析似乎缺乏鉴别能力来检测神经心源性晕厥患者在倾斜试验期间已知会发生的交感迷走神经调节的快速和显著变化。
