Kato K, Watanabe Y, Shimaji T, Hishida H
Fujita Health University, Department of Internal Medicine.
Nihon Rinsho. 1995 Feb;53(2):334-9.
Signal-averaged electrocardiograms (SAEs) were recorded from 28 unipolar leads placed on the upper body in patients with previous myocardial infarction (MI). We measured the filtered QRS duration (fQRSd) for each lead to obtain a new parameter, called a "departure ratio (DR)". The DR was the standardized difference between the fQRSd of a patient and the mean fQRSd obtained in the healthy controls in each of the 28 leads. A DR map was then constructed using the DR. Patients with sustained ventricular tachycardia (VT) demonstrated a small negative area surrounded by dense, positive iso-DR lines and/or a large maximum. These features were located on the left anterior chest through the left back in patients with anterior MI and on the right lateral to the right anterior chest in patients with inferior MI. Both of these characteristic patterns in the area corresponding to the infarct site were present in few patients without VT. These characteristic patterns were highly correlated with the occurrence of sustained VT, suggesting that the characteristics of the DR map represent the body surface manifestation of delayed excitation conduction which can be a sustained VT substrate. Our results indicate that the DR map based on the fQRSd on SAE provides useful information that could not be obtained from vector magnitude analysis.
对既往有心肌梗死（MI）的患者，从置于上身的28个单极导联记录信号平均心电图（SAE）。我们测量每个导联的滤波QRS波时限（fQRSd）以获得一个新参数，称为“偏离率（DR）”。DR是患者的fQRSd与28个导联中每个导联健康对照者获得的平均fQRSd之间的标准化差值。然后使用DR构建DR图。持续性室性心动过速（VT）患者表现为一个小的负性区域，周围环绕着密集的正性等DR线和/或一个大的最大值。这些特征在前壁心肌梗死患者中位于左前胸至左后背，在下壁心肌梗死患者中位于右前胸至右外侧。在无VT的少数患者中，梗死部位对应的区域均不存在这两种特征性模式。这些特征性模式与持续性VT的发生高度相关，提示DR图的特征代表了延迟激动传导的体表表现，而延迟激动传导可能是持续性VT的基质。我们的结果表明，基于SAE上fQRSd的DR图提供了从向量幅度分析中无法获得的有用信息。
