所谓“不定型心电轴”是指心电图上所有六个额面导联均呈双向波(RS或QR),向上和向下的波几乎相等。虽然在临床工作中这种类型的心电图经常遇到,但对其QRS环的特征至今没有得到解释,有人推测可能环体呈园形。但是经过心向量图的研究发现这种不定型心电轴的额面QRS向量非常窄,几 The so-called “unshaded ECG axis” means that all six frontal leads on the ECG display a bidirectional wave (RS or QR), and the waves up and down are almost equal. Although this type of electrocardiogram is often encountered in clinical work, the characteristics of its QRS ring have not been explained so far, and it has been speculated that the ring may be circular. However, after the study of the cardiac vector diagram found that this unstructured ECG axis QRS vector is very narrow, a few