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 ...

THE electrocardiographic picture of prolonged QRS-complex duration with short PR interval was the subject of isolated reports 1,2 until Wolff, Parkinson and White 3 described the clinical syndrome of ...

A first-degree AV node block occurs when conduction through the AV node is slowed, thus delaying the time it takes for the action potential to travel from the SA node, through the AV node, and to the ...