However, the P wave or T wave axis can also be measured ... some shortcuts to quickly determine the axis are outlined below. The normal QRS axis should be between -30 and +90 degrees.

The ability to identify an abnormality on the 12-lead ECG, suggestive of underlying cardiac disease associated with sudden cardiac death (SCD), is based on a sound working knowledge of the normal ECG ...

Determine Heart Rate on the ECG To determine whether bradycardia, a normal ... P wave, and the ventricular rate, which is measured by the rate of the QRS complex. Read Determining Rate. The axis ...