EMS Registry ReadyExample 1 · lead II · 6 seconds
- Rate
- 73/min8 QRS complexes in 6 seconds × 10 = 80/min
- Rhythm
- Regular
- P waves
- Upright in II, uniform
- P to QRS
- 1:1, a P before every QRS
- PR
- 0.18 s
- QRS
- 0.09 s, narrow
Normal sinus rhythm on an ECG strip
Regular at 60-100/min, an upright P before every QRS, a PR of 0.12-0.20 s and a narrow QRS.
What to look for
Regular, at 60-100/min. Look for an upright P wave in II before every QRS, a constant PR of 0.12-0.20 s, and a narrow QRS.
Examples
Each strip is 6 seconds of lead II, drawn to scale (25 mm a second, 10 mm a millivolt), so you can count boxes the way you would on paper. Each one is a different example, measured below it.
Example 2 · lead II · 6 seconds
- Rate
- 90/min9 QRS complexes in 6 seconds × 10 = 90/min
- Rhythm
- Regular
- P waves
- Upright in II, uniform
- P to QRS
- 1:1, a P before every QRS
- PR
- 0.12 s
- QRS
- 0.08 s, narrow
Example 3 · lead II · 6 seconds
- Rate
- 62/min6 QRS complexes in 6 seconds × 10 = 60/min
- Rhythm
- Regular
- P waves
- Upright in II, uniform
- P to QRS
- 1:1, a P before every QRS
- PR
- 0.16 s
- QRS
- 0.08 s, narrow
Don't confuse it with
- Sinus bradycardia
Everything normal sinus rhythm has, but under 60/min.
- Sinus tachycardia
Sinus rhythm over 100/min: regular, with an upright P before every QRS.
- First-degree AV block
Sinus rhythm with every P conducted, but a constant PR over 0.20 s.
Want a new strip every time? The ECG Drill in the app draws a fresh, measured example on every try and steers you toward the rhythms you miss. It's part of the Paramedic level, and you can try 5 strips a day free.
Try the ECG Drill