Huikuri H V, Niemelä M J, Ojala S, Rantala A, Ikäheimo M J, Airaksinen K E
Department of Medicine, University of Oulu, Finland.
Circulation. 1994 Jul;90(1):121-6. doi: 10.1161/01.cir.90.1.121.
Altered neural regulation of the cardiovascular system may be an important factor for various manifestations of ischemic heart disease. This research was designed to compare the circadian rhythm of cardiac neural regulation and autonomic responses to arousal and upright posture between patients with uncomplicated coronary artery disease (CAD) and age-matched subjects with no evidence of heart disease.
Twenty-four-hour heart rate variability (HRV) in the frequency domain was analyzed in 20 male patients (mean age, 52 +/- 7 years) with angiographic evidence of CAD without prior myocardial infarction and in 20 healthy men (mean age, 51 +/- 8 years) with no clinical, echocardiographic, or exercise ECG evidence of heart disease. None of the 24-hour average frequency-domain components of HRV differed significantly between the two groups. Healthy subjects had a significant circadian rhythm of normalized units of high-frequency (HF) power of HRV with higher values during sleep. Normalized units of low-frequency (LF) power and the LF/HF ratio also showed a significant circadian rhythm in healthy subjects, with higher values during the daytime. No significant circadian rhythms in any of the normalized spectral components of HRV were observed in patients with CAD, and the night-day difference in LF/HF ratio was smaller in the patients with CAD than in the healthy subjects (0.5 +/- 1.4 versus 1.8 +/- 0.7, P < .001). Awakening when in the supine position resulted in a significant increase in the LF/HF ratio (P < .01) in the healthy subjects, but no significant changes in HRV were observed after awakening in patients with CAD. Assumption of upright position resulted in a comparable decrease in the components of HRV between the groups.
The circadian rhythm of cardiac neural regulation is altered in patients with uncomplicated CAD. Reduced autonomic responses to sleep-wake rhythm suggest that the modulation of cardiac autonomic function by stimuli from the central nervous system is impaired in CAD.
心血管系统神经调节改变可能是缺血性心脏病各种表现的重要因素。本研究旨在比较单纯性冠状动脉疾病（CAD）患者与年龄匹配的无心脏病证据的受试者之间心脏神经调节的昼夜节律以及对唤醒和直立姿势的自主反应。
对20例有冠状动脉造影证据但无既往心肌梗死的男性CAD患者（平均年龄52±7岁）和20例无心脏病临床、超声心动图或运动心电图证据的健康男性（平均年龄51±8岁）进行了24小时心率变异性（HRV）频域分析。两组之间HRV的24小时平均频域成分均无显著差异。健康受试者HRV高频（HF）功率归一化单位有显著的昼夜节律，睡眠期间值更高。低频（LF）功率归一化单位和LF/HF比值在健康受试者中也显示出显著的昼夜节律，白天值更高。CAD患者未观察到HRV任何归一化频谱成分有显著的昼夜节律，CAD患者LF/HF比值的昼夜差异小于健康受试者（0.5±1.4对1.8±0.7，P<.001）。健康受试者仰卧位醒来时LF/HF比值显著增加（P<.01），但CAD患者醒来后HRV未观察到显著变化。两组直立姿势时HRV成分下降程度相当。
单纯性CAD患者心脏神经调节的昼夜节律发生改变。对睡眠-觉醒节律的自主反应降低表明CAD患者中枢神经系统刺激对心脏自主功能的调节受损。
