The image below shows the typical findings of a left bundle branch block in the precordial ECG leads. Note: If the QRS duration is 100 to 119 ms with criteria 2, 3 and 4 of the above, an ...

from the Division of Cardiology and Department of Emergency Medicine at the Virginia Commonwealth University in Richmond, VA, looked at patients who had LBBB on their initial ECG and presented ...

This ECG displays an accelerated idioventricular rhythm. This has a left bundle branch block pattern and is a good example of the AV dissociation that occurs. Now, look at the rhythm strip at the ...