家兔急性实验性心肌缺血模型高频心电图变化的探讨

STUDIES ON CHANGES OF HIGH FREQUENCY ELECTROCARDIOGRAM DURING THE EXPERIMENTAL MODEL OF ACUTE MYOCARDIAL ISCHEMEA IN RABBITS

Through the analysis of the HF-ECG of eight models of myocardial ischemea and five models of myocardial damages on five rabbits, it was found that the type of QRS wave of Channels X, Y and Z remained unchanged, maintaining the qR, qRs and RS wave type which had existed before myocardial ischemea or myocardial damages were induced. The occurring phase of the notch and the slur of the high-frequency components had little change. The notch in most cases situated on the top of the QRS waves. The slur mainly situated in the middle region of the rising slope, and the middle and bottom regions of the descending slope of the QRS waves. the number and the level of the notch and the slur increased as the myocardial condition became severe. The myocardial ischemea model was reversible: 10 to 15 minutes after injection, the number and the level of the high-frequency components reached the peak, but 20 minutes later they recovered. The model of myocardial damages was, however, irreversible. Its number and level of the notch and the slur were greater than those in the model of the myocardial ischemea. Besides, its QRS waves showed an even top, which might be regarded as another indication of the high-frequency components of the HF-ECG. The correlation between the number and level of the notch and the slur in the HF-ECF, and the intensity of the myocardial condition indicates that the latter can be estimated by the intact HF-ECG method. However, its cellular eletrophysiological mechanism still needs further experimental studies.