For example, the normal QRS complex in lead V1 does not contain a ... The QRS duration will lengthen when electrical activity takes a long time to travel throughout the ventricular myocardium.

Because the normal ventricular conduction system (His-Purkinje) is used, the QRS complex is frequently narrow. A junctional rhythm is normally slow — less than 60 beats per minute. When faster ...

The QRS complex duration (0.08 sec ... at many major teaching hospitals in Massachusetts. In his limited free time he enjoys photography, music, and reading.