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 ...

Ventricular tachycardia can occur with many variations of the QRS morphology, depending on where the arrhythmia originates, which sometimes makes diagnosis on ECG challenging. Below are two ...