冠心病心肌缺血发作时自主神经功能的变化

The Changes of Autonomic Nervous Function on Attacks of Myocardial Ischemia in Coronary Heart Disease

采用心率变异性（ＨＲＶ）自回归（ＡＲ）和快速傅立叶转换（ＦＦＴ）两种频域法对比分析５０例冠心病病人和５０例正常人ＨＲＶ的昼夜变化及心肌缺血时与无缺血时的ＨＲＶ变化，并对两种频域法进行相关性分析。结果表明：冠心病组和对照组的ＨＲＶ呈昼夜变化，白天以低频成分（ＬＦ，代表交感神经活性）占优势，夜间以高频成分（ＨＦ，反映迷走神经活性）占优势；冠心病心肌缺血病人的ＨＲＶ昼夜变化减少（ＡＲ法，ＬＦ／ＨＦ：冠心病组为２．２±０．９ＶＳ０．８±１．１，对照组为２．４±１．２ＶＳ０．３±０．８，Ｐ＜０．０５），清晨自主神经调节发生突然变化，即由迷走神经兴奋转为交感神经兴奋；劳累型心绞痛病人心肌缺血时ＬＦ增高（１６３±１３２ｍｓ２ＶＳ２４７±１６２ｍｓ２，Ｐ＜０．０５），ＨＦ减少（７５±２１ｍｓ２ＶＳ５７±１１ｍｓ２，Ｐ＜０．０５），心肌缺血次数与ＬＦ呈正相关（ｒ＝０．６７）．上午６～１０时心肌缺血发生最多。两种能谱估计法呈高度正相关（ｒ＝０．９８）。提示：劳累型心绞痛的发作与交感神经功能亢进、迷走神经张力减弱有关；清晨自主神经功能调节的突然变化可起板机作用，使此时心肌缺血的发生频度增高。

The circadian variations of heart rate variability(HRV)in 50 patients with coronary heart disease and in 50 normal persons were analyzed.The changes of HRV on attacks of ischemia were compared with that of no ischemia by autoregressive analysis(AR)and fast Fourier transform analysis(FFT).The results showed that LF(low frequency component,representing sympathytic nervous activity)occupied a dominan position on day time and HF(high frequency component,representing vagal nervous activity)at night time both in two groups.Ciacadian variations of HRV in coronary heart disease reduced(AR,coronary heart disease 2.2±0.9 VS 0.8±1.1 normal person 2.4±1.2 VS 0.3±0.8,P<0.05).There was a sudden change of autonomic nervous regulation in early morning,exhibiting that vagal hyperactivity transformed sympathytic hyperactivity.On occurance of ischemia in patients with exerting angina,LF increased(163 ±132 ms2 VS 247±162 ms2,P<0.05)and HF decreased(75±21ms2VS51±11ms2,P<0.05).The number of ischemia were related positively to LF(r=0.67)and increased during the morning(6:00～10:00 Am).There was a marked positive correlation between two spectral analysis methods(r=0.98).The study suggested occurence of ischemia in exerting angina could be assosiated with sympathytic hyperactivity and vagal hyperactivity.The sudden change of autonomic nervous regulation might play trriger action,which could accelerate the peak occurence of ischemia in this time.