Left axis deviation is between -30 and -90 degrees.

左轴偏移在-30和-90度之间。

The rest is known as northwest axis or extreme axis deviation.

其余称为西北轴或极端轴偏移。

Negative values of the QRS complex in both leads are indicative of extreme axis deviation.

两个导联的QRS波群均为负值，表明存在极端轴偏移。

A positive value in lead I and negative in lead aVF, place the axis in the upper left quadrant, which interprets as possible left axis deviation.

如果导联I为正值，导联aVF为负值，则将轴放置在左上象限，解释为可能是左轴偏移。