心率能谱分析检测冠心病阵发性心肌缺血时的植物神经活动

AUTONOMIC NERVOUS ACTIVITY AT ERISODES OF MYOCARKIAL ISCHEMIA IN PATIENTS WITH CORONARY ARTERY DISEAES BY HEART RATE POWER WPECTRAL ANALYSIS

对４４例冠心病患者２４小时的动态心电图进行了心率能谱分析，共发现阵发性缺血型ＳＴ段水平或下垂型压低≥０．１ｍＶ１９５阵，对ＳＴ段压低最深时和其发作前的４分钟心率能谱图之低频（ＬＦ）、高频（ＨＦ）波范围面积和ＬＦ与ＨＦ波面积比值进行了比较。发生在夜间的快频率心肌缺血的ＨＦ波面积明显降低，Ｐ＜０．００１；ＬＦ与ＨＦ面积比值显著增大，Ｐ＜０．０５；而ＬＦ波面积略有增加。提示此类心肌缺血发作时存在植物神经活性改变，副交感神经张力明显降低，可能有继发的交感神经活性增高。

eart rate power spectral analysis in 4 4 patients with coronary artery disease was obtained from 2 4-hour dynamic electrocardiogram.195 episodes of transient myocardial ischemia that was defined as horizon-tal or down sloping depression of the ST segment of≥0. 1 mV and lasted for≥2 minutes were studied。The area of low frequency components(LF,0. 02～0. 10 Hz)representing predominontly sympathetic tone with some contribution from the parasympathetic tone and that of high frequency components(HF,0.15～0. 40 Hz)representing mainly parasympathetic tone and the value of LF/ HF on 4 minute heart rate pow-er spectral graph at the deepest depression of ST segment were compared with that before the episode ofmyocardial ischemia。 The area of HF of fast rate myocardial ischemia occurring in night reduces significant-ly(P<0. 001), the value of LF/HF increases markedly(P<0. 05)and the area of IF increases slightly.The results suggest that there is a change of autonomic nervous activity during the episode of fast rate my-ocardial ischemia in night, parasympathetic nervous tone decreases markedly,there may be secondary in-crease of sympathetic nervous activity。