室速与室上速伴差传均为宽QRS波心动过速,两者的鉴别是一项重要的基本功,应用特征不同的心电图图形进行两者的鉴别已经广泛应用,本文介绍右3左1法则。[定义]鉴别室速与室上速的心电图图形标准(morphologic criteria)是指心电图某些导联的QRS波形态只在室速时出现,而室上速伴室内差传时不可能存在。因此,一旦宽QRS波心动过速的心电图存在这些图形, VT and SVS are wide QRS tachycardia, the identification of the two is an important basic skills, the use of different characteristics of ECG identification of the two has been widely used, this article describes the right 3 left 1 law. [DEFINITIONS] Electrocardiogram to identify VT and SVS The morphologic criteria are those in which QRS patterns in some leads of the ECG appear only at VT but not in SS. Therefore, once the wide QRS tachycardia ECG exist these patterns,