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.

New worksheetPractise online with hints

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

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
2.Easy
II25 mm/s · 10 mm/mV

Measure the QRS duration 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
QRS = s
3.Medium
II25 mm/s · 10 mm/mVsupraventricular tachycardia (SVT)atrial flutter, 2:1 conductionventricular tachycardiasinus 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. 1supraventricular tachycardia (SVT)
  2. 2atrial flutter, 2:1 conduction
  3. 3ventricular tachycardia
  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 Fridericia’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/mV

This lead II strip shows second-degree AV block type I (Wenckebach). How many P waves per group are there, counting the non-conducted one (the n of an n:(n − 1) block)?

lead II, 25 mm/s, 10 mm/mV1 small box = 0.04 s, 1 large box = 0.20 sstrip length 6 s
P waves per group =
6.Hard
II25 mm/s · 10 mm/mVsynchronised cardioversionCPR (non-shockable rhythm)transcutaneous pacingimmediate defibrillation

A patient without a palpable pulse has this organised rhythm on the monitor (pulseless electrical activity). Which treatment do adult resuscitation guidelines name for 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. 1synchronised cardioversion
  2. 2CPR (non-shockable rhythm)
  3. 3transcutaneous pacing
  4. 4immediate defibrillation

Answer key

  1. 1. PR = 0.28 s
  2. 2. QRS = 0.06 s
  3. 3. supraventricular tachycardia (SVT)
  4. 4. QTc = 0.48 s
  5. 5. P waves per group = 3
  6. 6. CPR (non-shockable rhythm)

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