- The QRS represents ventricular depolarization.
- It is very important to analyze each QRS complex on the tracing and report the duration measurement and describe the shape (including any changes in shape).
- As discussed earlier in step 3, when referring to P waves, remember changes in the shape of the waveform can indicate the locus of stimulation has changed or a different conduction pathway was followed. It is no different when analyzing the QRS complex.
- The difference is that in step 3, we were looking at atrial activity. Now we are looking at ventricular activity.
- Measure from the beginning to the end of ventricular depolarization.
- The normal duration of the QRS complex measures from: 0.06 – 0.10 second
- When the QRS measurement is 0.12 seconds or greater it indicates a delay in the electrical impulse as it is passing through the ventricular conduction system
- Abnormal duration QRS