Ventricular tachycardia arises from an abnormal electrical focus or circuit in the myocardium of the ventricle and is usually manifested as a tachyarrhythmia with a wide QRS complex on ...
The PR interval is the time from the beginning of the P wave (atrial depolarization) to the beginning of the QRS complex (ventricular depolarization). The normal PR interval measures 0.12-0.20 seconds ...