Yakubo S, Ozawa Y, Komaki K
Kasukabe Municipal Hospital, Saitama, Japan.
J Electrocardiol. 1995;28 Suppl:234-8. doi: 10.1016/s0022-0736(95)80064-6.
The purpose of this experiment is to study the possibility of intra-QRS high-frequency electrocardiographic (HFECG) changes for the evaluation of and recovery from myocardial ischemia in both the time-domain and spectral-turbulence analyses on the signal-averaged ECG using the Holter ECG monitoring (Holter SAECG) system. A balloon catheter was inserted into the left anterior descending coronary artery (LAD of 8 mongrel dogs and was maintained inflated for 2 hours to occlude the LAD and then was deflated to allow for reperfusion. The cardiac signal from the three orthogonal leads of the surface ECG (X, Y, and Z) was recorded and analyzed with a Del Mar Avionics (model 459, Irvine, CA) recorder and analyzer (model 563). The Holter SAECG was assessed before the LAD occlusion phase (control), during the coronary occlusion phase (ischemia), after the reperfusion phase (recovery). To evaluate intra-QRS ECG changes in the time-domain analysis, root-mean-square (RMS) voltage of the entire QRS in 40-250 HZ (40 RMS), 100-250 Hz (100 RMS), and 150-250 Hz (150 RMS) were studied and the vector magnitude of the QRS was depicted. In the spectral-turbulence analysis and spectrocardiogram to study the discordance of the ECG wave front velocity by fast Fourier transformation analysis, the interslice correlation mean (IC mean) and interslice correlation standard deviation (IC SD), which were calculated as the mean and standard deviation of the Pearson correlation coefficient of each time slice with its neighbor, were investigated. In the time-domain analysis, the LAD occlusion by balloon catheter at ischemia produced a reduction in 40 RMS, 100 RMS, and 150 RMS, while a restoration was seen at recovery in 40 RMS and 100 RMS. In the spectral-turbulence analysis, LAD occlusion at ischemia caused a decrease in IC mean and an increase in IC SD. The waveform of the vector magnitude and the spectrocardiogram seen at control showed changes with ischemia and was restored at recovery with the coronary reperfusion. It was thought possible to capture the intra-QRS HFECG changes that occur during myocardial ischemia and recovery from it in the time-domain analysis and spectral-turbulence analysis on the Holter SAECG system in spite of the limitation of this methodology. To evaluate myocardial ischemia and recovery, this method should be useful clinically.
本实验的目的是利用动态心电图监测（动态平均心电图，Holter SAECG）系统，通过对信号平均心电图进行时域和频谱紊乱分析，研究QRS波内高频心电图（HFECG）变化用于评估心肌缺血及恢复情况的可能性。将一根球囊导管插入8只杂种犬的左前降支冠状动脉（LAD），使其充气保持2小时以阻断LAD，然后放气以实现再灌注。利用德尔玛航空电子公司（型号459，加利福尼亚州欧文市）的记录仪和分析仪（型号563）记录并分析体表心电图三个正交导联（X、Y和Z）的心脏信号。在LAD闭塞阶段（对照）、冠状动脉闭塞阶段（缺血）、再灌注阶段（恢复）对动态平均心电图进行评估。为了在时域分析中评估QRS波内心电图变化，研究了40 - 250赫兹（40 RMS）、100 - 250赫兹（100 RMS）和150 - 250赫兹（150 RMS）范围内整个QRS波的均方根（RMS）电压，并描绘了QRS波的向量大小。在频谱紊乱分析和通过快速傅里叶变换分析研究心电图波前速度不一致性的频谱心电图中，研究了切片间相关均值（IC均值）和切片间相关标准差（IC标准差），它们分别计算为每个时间切片与其相邻切片的皮尔逊相关系数的均值和标准差。在时域分析中，缺血时球囊导管阻断LAD导致40 RMS、100 RMS和150 RMS降低，而在恢复阶段40 RMS和100 RMS恢复。在频谱紊乱分析中，缺血时LAD闭塞导致IC均值降低和IC标准差增加。对照时观察到的向量大小波形和频谱心电图在缺血时出现变化，并在冠状动脉再灌注恢复时恢复。尽管该方法存在局限性，但认为在动态平均心电图系统的时域分析和频谱紊乱分析中能够捕捉到心肌缺血及其恢复过程中发生的QRS波内高频心电图变化。为了评估心肌缺血和恢复情况，该方法在临床上应具有实用性。
