Gomis P, Jones D L, Caminal P, Berbari E J, Lander P
Industrial Technology Department, University Simón Bolívar, La Guaira, Venezuela.
IEEE Trans Biomed Eng. 1997 Aug;44(8):681-93. doi: 10.1109/10.605425.
This paper presents a new, quantitative approach to measuring abnormal intra-QRS signals, using the high-resolution electrocardiogram (HRECG). These signals are conventionally known as QRS "notches and slurs." They are measured qualitatively and form the basis for the ECG identification of myocardial infarction. The HRECG is used for detection of ventricular late potentials (LP), which are linked with the presence of a reentry substrate for ventricular tachycardia (VT) after a myocardial infarction. LP's are defined as signals from areas of delayed conduction which outlast the normal QRS period. Our objective is to quantify very low-level abnormal signals that may not outlast the normal QRS period. In this work, abnormal intra-QRS potentials (AIQP) were characterized by removing the predictable, smooth part of the QRS from the original waveform. This was represented as the impulse response of an ARX parametric model, with model order selected empirically from a training data set. AIQP were estimated using the residual of the modeling procedure. Critical AIQP parameters to separate VT and non-VT subjects were obtained using discriminant functions. Results suggest that AIQP indexes are a new predictive index of the HRECG for VT. The concept of abnormal intra-QRS potentials permits the characterization of pathophysiological signals contained wholly within the normal QRS period, but related to arrhythmogenesis. The new method may have other applications, such as detection of myocardial ischemia and improved ECG identification of the site of myocardial infarction, particularly in the absence of Q waves.
本文提出了一种使用高分辨率心电图（HRECG）测量QRS波内异常信号的新的定量方法。这些信号通常被称为QRS“切迹和顿挫”。它们通过定性测量，并构成心电图识别心肌梗死的基础。HRECG用于检测心室晚电位（LP），心室晚电位与心肌梗死后室性心动过速（VT）折返基质的存在有关。LP被定义为来自传导延迟区域且持续时间超过正常QRS波时限的信号。我们的目标是量化可能不会超过正常QRS波时限的极低水平异常信号。在这项工作中，通过从原始波形中去除QRS波可预测的平滑部分来表征QRS波内异常电位（AIQP）。这被表示为ARX参数模型的脉冲响应，模型阶数从训练数据集中凭经验选择。使用建模过程的残差估计AIQP。使用判别函数获得区分室性心动过速和非室性心动过速受试者的关键AIQP参数。结果表明，AIQP指标是HRECG用于室性心动过速的一种新的预测指标。QRS波内异常电位的概念允许对完全包含在正常QRS波时限内但与心律失常发生相关的病理生理信号进行表征。这种新方法可能有其他应用，如检测心肌缺血和改进心电图对心肌梗死部位的识别，特别是在没有Q波的情况下。
