Heart Rate

60-100 BPM

Rhythm Regularity

Regular -- R-to-R intervals are consistent throughout the strip

P Wave Presence

Present BEFORE every single QRS complex

P Wave Morphology

Upright and positive in leads I, II, and VF

PR Interval

0.12 -- 0.20 seconds

QRS Duration

Less than 0.12 seconds -- narrow

T Wave

Upright in most leads; same direction as QRS complex