RATE

ventricular rate

count between 2 R waves (R & R’)

atrial rate

count between 2 P waves (P & P')

tachycardia

> 100 bpm or < 3 big boxes in between 2 beats

bradycardia

< 60 bpm or > 5 big boxes in between 2 beats

Tachycardia and bradycardia can be benign, physiologic occurences in sinus tachycardia or sinus bradycardia, or pathologic occurences in tachyarrhythmia or bradyarrhythmia