心肌缺血时心电信息中高频成分的动态变化研究

以狗作为冠脉缺血的实验模型，观察心肌缺血前和心肌缺血后不同时间段时心电信息中高频成分的动态变化。发现小范围心肌缺血和大范围心肌缺血的早期，高频心电图中的切迹个数及切迹的深度和宽度与正常时相比均有明显增加。切迹在ＱＲＳ综合波时段上的分布与缺血部位有一定的相关性。在心肌缺血发展过程中高频成分中的切迹和转折可互相转化。心肌缺血时高频心电信息中的Ｐ—ＱＲＳ—Ｔ综合波变异率明显高于正常时。表明：心电信息中的高频成分对心肌小范围病变和心肌缺血发展过程中的动态变化较敏感。对高频成分的动态分析，能更有效地反映临床心肌缺血的状况。

ANALYZING DYNAMIC CHANGES OF HIGH-FREQUENCY COMPONENT IN ELECTROCARDIAC SIGNAL OF MYOCARDIAL ISCHEMIA

Using dog as experiment model of myocardial ischemia, the dynamic changes of high-frequency component in electrocardiac signal during various periods before and after coronary artery ligated were studied. We found that the total and abnormal numbers of notches of high-frequency electrocardiogram(HFECG) significantly increased in small range myocardial ischemia or infarction and in early period of large range myocardial ischemia or infarction. Compared with that befor and after coronary artery religated. The distribution of notches within QRS complex presents partial relationship with the position of ischemia. The slurs and notches in HFECG can exchange each other during the developing of myocardial ischemia. Compared with normal the variability index of beat-to-beat P-QRS-T complex in HFECG increased significantly during myocardial ischemia. Our results suggested that the high-frequency component of electrocardial signal is more sensitive to small pathological changes in heart and the dynamic changes during the developing of myocardial ischemia. In clinical the dynamically analyzing of high-frequency component can reflect the condition of myocardial ischemia more effectively.