ECG rhythm strip interpretation worksheet with answers

Free printable ECG rhythm strip interpretation worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
II25 mm/s · 10 mm/mV

The rhythm on this lead II strip is regular. Use the 300 method (300 ÷ the number of large boxes between two consecutive R waves) to estimate the heart rate in beats per minute, rounded to a whole number.

lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
heart rate = bpm
2.Easy
II25 mm/s · 10 mm/mV

Measure the PR interval on this lead II strip, in seconds.

lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
PR = s
3.Medium
II25 mm/s · 10 mm/mVsinus bradycardiajunctional rhythmfirst-degree AV blocksinus tachycardia

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
  1. 1sinus bradycardia
  2. 2junctional rhythm
  3. 3first-degree AV block
  4. 4sinus tachycardia
4.Medium
II25 mm/s · 10 mm/mV

Measure the QT interval and the R–R interval on this regular lead II strip, then calculate the rate-corrected QTc with Bazett’s formula QTc = QT/√RR (both in seconds). Give the answer in seconds to three decimals.

lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
QTc = s
5.Hard
II25 mm/s · 10 mm/mVidioventricular rhythmthird-degree (complete) AV blockasystoleventricular tachycardia

Identify the rhythm on this 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
  1. 1idioventricular rhythm
  2. 2third-degree (complete) AV block
  3. 3asystole
  4. 4ventricular tachycardia
6.Hard
II25 mm/s · 10 mm/mVthird-degree (complete) AV blocksinus rhythm with wide QRSdual-chamber (AV) paced rhythmventricular paced rhythm

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
  1. 1third-degree (complete) AV block
  2. 2sinus rhythm with wide QRS
  3. 3dual-chamber (AV) paced rhythm
  4. 4ventricular paced rhythm

Answer key

  1. 1. heart rate = 60 bpm
  2. 2. PR = 0.16 s
  3. 3. first-degree AV block
  4. 4. QTc = 0.451 s
  5. 5. idioventricular rhythm
  6. 6. ventricular paced rhythm

Full step-by-step solutions: practise this topic on examproblems.com.