15例健康受试者在仰卧位休息时,用药物控制心脏迷走神经张力来检测心率变化的11项指标及其之间的相关性。在静脉注射普萘洛尔消除交感神经影响后,于控制呼吸(0.25Hz)下,测定10分钟RR间距的变化;再用阿托品完全阻断迷走神经后测定RR间距的缩短。对域指数(标准差、变异系数和平均连续差)同迷走神经张力显著相关(r分别为0.87、0.81和0.92,P均<0.01)。自回归谱分析(权的平方根和分量方差系数)和快速傅里叶变换(平均振幅)表明,高频分量(0.25Hz)的频域指标同迷走神经张力相关 Fifteen healthy subjects, resting in the supine position, monitored 11 indicators of heart rate variability with drug-controlled cardiac vagal tone and their correlation. After intravenous injection of propranolol to eliminate sympathetic effects, the change in RR interval was measured at 10 min after controlled respiration (0.25 Hz). Shortening of the RR interval was then measured after the vagus nerve was completely blocked with atropine. The index of the domain (standard deviation, coefficient of variation and mean continuous difference) were significantly correlated with vagal tone (r = 0.87, 0.81 and 0.92, respectively, P <0.01). Autoregressive spectral analysis (square root of the weight and component variance coefficient) and fast Fourier transform (average amplitude) show that the frequency domain index of the high frequency component (0.25 Hz) is correlated with vagal tone