Measure the PR interval on this lead II strip, in seconds.
ECG rhythm strip interpretation worksheet with answers
1.Easy
lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
PR = s
2.Easy
Look at the R–R intervals on this lead II strip. How would you describe the ventricular rhythm? Click your answer.
lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
- 1regular
- 2regularly irregular
- 3irregularly irregular
3.Medium
Interpret this lead II rhythm strip. Which rhythm is it? Click your answer.
lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
- 1sinus tachycardia
- 2atrial fibrillation
- 3supraventricular tachycardia (SVT)
- 4accelerated junctional rhythm
4.Medium
This lead II strip shows sinus rhythm with one pause. Measure the pause, the R–R interval across it, in seconds.
lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
pause = s
5.Hard
This patient has a pacemaker. Interpret the lead II strip. Click your answer.
lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
- 1dual-chamber (AV) paced rhythm
- 2paced rhythm, failure to capture
- 3third-degree (complete) AV block
- 4sinus rhythm with wide QRS
6.Hard
Interpret this lead II strip with the five steps in order: rate, rhythm, P waves, PR interval, QRS duration. At which step do you find the first abnormal finding? Click it.
lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
- 1rate
- 2rhythm
- 3P waves
- 4PR interval
- 5QRS duration
Answer key
- 1. PR = 0.24 s
- 2. regularly irregular
- 3. supraventricular tachycardia (SVT)
- 4. pause = 1.6 s
- 5. dual-chamber (AV) paced rhythm
- 6. P waves
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