Casolo G, Balli E, Taddei T, Amuhasi J, Gori C
Clinica Medica I, University of Florence, Italy.
Am J Cardiol. 1989 Nov 15;64(18):1162-7. doi: 10.1016/0002-9149(89)90871-0.
Heart rate (HR) variability is a noninvasive index of the neural activity of the heart. Although also dependent on the sympathetic activity of the heart, HR variability is mainly determined by the vagal outflow of the heart. Several HR abnormalities have been described in patients with congestive heart failure (CHF); however, there are no data on HR variability in CHF patients. In the present study HR variability was assessed in 20 CHF patients and 20 control subjects from 24-hour Holter tapes. HR variability was evaluated by calculating the mean hourly HR standard deviation and by analyzing the 24-hour RR histogram. Mean hourly HR standard deviation was markedly and significantly reduced in CHF patients both over the 24-hour period (97.5 +/- 41 vs 233.2 +/- 26 ms, p less than 0.001) as well as during most of the individual hours examined. The 24-hour RR histogram of CHF patients had a different shape and had a decreased variation compared to control subjects (total variability 356 +/- 102 vs 757 +/- 156 ms, p less than 0.001). Thus, CHF patients with depressed ejection fraction (less than 30%) have a low HR variability compared to normal individuals. This result can be interpreted as adjunctive evidence for decreased parasympathetic activity to the heart during CHF.
心率（HR）变异性是心脏神经活动的一种非侵入性指标。虽然心率变异性也依赖于心脏的交感神经活动，但其主要由心脏的迷走神经传出决定。已有多项心率异常在充血性心力衰竭（CHF）患者中被描述；然而，尚无关于CHF患者心率变异性的数据。在本研究中，通过24小时动态心电图监测对20例CHF患者和20例对照者的心率变异性进行评估。通过计算每小时平均心率标准差并分析24小时RR间期直方图来评估心率变异性。CHF患者在24小时期间（97.5±41对233.2±26毫秒，p<0.001）以及在大多数所检查的单个小时内，每小时平均心率标准差均显著降低。与对照者相比，CHF患者的24小时RR间期直方图形状不同且变异减少（总变异356±102对757±156毫秒，p<0.001）。因此，射血分数降低（小于30%）的CHF患者与正常个体相比心率变异性较低。这一结果可被解释为CHF期间心脏副交感神经活动降低的辅助证据。
