Baker Jacquie, Racosta Juan M, Balint Brittany, Kimpinski Kurt
Department of Clinical Neurological Sciences, University Hospital, London Health Sciences Centre, London, ON, Canada.
School of Kinesiology, Western University, London, ON, Canada.
J Clin Neurophysiol. 2018 Mar;35(2):123-129. doi: 10.1097/WNP.0000000000000452.
The clinical significance of heart rate variability in the context of autonomic dysfunction continues to be a matter of debate. A consensus is lacking on the best heart rate variability measures for clinical purposes. Therefore, the purpose of this study was to investigate the utility of heart rate variability parameters in healthy versus autonomic dysfunction.
Healthy young (n = 134), healthy older (n = 32), and patients with mild (postural tachycardia syndrome; n = 25) and severe (neurogenic orthostatic hypotension; n = 34) autonomic dysfunction were included. Time and frequency parameters during baseline, head-up tilt (HUT), and heart rate response to deep breathing (HRDB) were compared.
Cardiovagal time parameters were significantly reduced during HUT in healthy young and postural tachycardia syndrome (P < 0.001). Healthy young had significantly higher time parameters during baseline, HUT, and HRDB (P < 0.01). This was reflected by a significantly lower resting heart rate (HR) (61.4 ± 9.0 bpm vs. 76.8 ± 13.6 bpm; P < 0.001) and a smaller [INCREMENT]HR during HUT (32.8 ± 10.5 bpm vs. 44.4 ± 13.3 bpm; P < 0.001). Time parameters increased in young and postural tachycardia syndrome during HRDB, which was characterized by a nonsignificant difference in [INCREMENT]HR between both groups. Time parameters were significantly higher in healthy old versus neurogenic orthostatic hypotension at rest and during HRDB (P < 0.05). During HUT, only the SD of all normal RR intervals remained significantly higher. Heart rate changes corroborated these findings. Resting HR was significantly lower in healthy older (62.6 ± 11.0 bpm vs. 70.7 ± 12.4 bpm), and [INCREMENT]HR during HRDB was significantly higher (15.9 ± 9.2 bpm vs. 3.9 ± 4.2 bpm; P < 0.001). During HUT, [INCREMENT]HR showed no significant differences.
Time domain parameters of heart rate variability have a greater utility than frequency parameters in clinical autonomic disorders.
心率变异性在自主神经功能障碍背景下的临床意义仍存在争议。对于临床应用而言，最佳的心率变异性测量方法尚未达成共识。因此，本研究旨在探讨心率变异性参数在健康人群与自主神经功能障碍患者中的应用价值。
纳入健康青年（n = 134）、健康老年（n = 32）以及轻度（体位性心动过速综合征；n = 25）和重度（神经源性直立性低血压；n = 34）自主神经功能障碍患者。比较基线、头高位倾斜试验（HUT）和深呼吸心率反应（HRDB）期间的时间和频率参数。
在健康青年和体位性心动过速综合征患者中，HUT期间的心脏迷走神经时间参数显著降低（P < 0.001）。健康青年在基线、HUT和HRDB期间的时间参数显著更高（P < 0.01）。这表现为静息心率（HR）显著更低（61.4 ± 9.0次/分钟 vs. 76.8 ± 13.6次/分钟；P < 0.001）以及HUT期间心率增加值（ΔHR）更小（32.8 ± 10.5次/分钟 vs. 44.4 ± 13.3次/分钟；P < 0.001）。在HRDB期间，青年和体位性心动过速综合征患者的时间参数增加，其特征是两组间ΔHR无显著差异。在静息和HRDB期间，健康老年患者的时间参数显著高于神经源性直立性低血压患者（P < 0.05）。在HUT期间，仅所有正常RR间期的标准差仍显著更高。心率变化证实了这些发现。健康老年患者的静息HR显著更低（62.6 ± 11.0次/分钟 vs. 70.7 ± 12.4次/分钟），且HRDB期间的ΔHR显著更高（15.9 ± 9.2次/分钟 vs. 3.9 ± 4.2次/分钟；P < 0.001）。在HUT期间，ΔHR无显著差异。
在临床自主神经疾病中，心率变异性的时域参数比频域参数具有更大的应用价值。
