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 ...

and found that LBBB was associated with a significantly higher risk of mortality compared to other ECG patterns, including RBBB and non-specific intraventricular conduction delay (NIVCD ...