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

This 6-second lead II strip is irregular, so the 300 and 1500 methods do not work. Use the 6-second method to estimate the ventricular heart rate in beats per minute.

lead II, 25 mm/s, 10 mm/mVstrip length 6 s (marks at 0, 3 and 6 s)
heart rate = bpm
2.Easy
II25 mm/s · 10 mm/mV

This lead II rhythm is regular. Count the small boxes between two consecutive R waves and use the 1500 method to find 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
3.Medium
II25 mm/s · 10 mm/mVnormal sinus rhythmatrial fibrillationjunctional rhythmsinus bradycardia

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. 1normal sinus rhythm
  2. 2atrial fibrillation
  3. 3junctional rhythm
  4. 4sinus bradycardia
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/mVdual-chamber (AV) paced rhythmsinus rhythm with wide QRSpaced rhythm, failure to capturejunctional 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. 1dual-chamber (AV) paced rhythm
  2. 2sinus rhythm with wide QRS
  3. 3paced rhythm, failure to capture
  4. 4junctional rhythm
6.Hard
II25 mm/s · 10 mm/mVidioventricular rhythmsupraventricular tachycardia (SVT)torsades de pointesatrial flutter, 2:1 conduction

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. 2supraventricular tachycardia (SVT)
  3. 3torsades de pointes
  4. 4atrial flutter, 2:1 conduction

Answer key

  1. 1. heart rate = 40 bpm
  2. 2. heart rate = 47 bpm
  3. 3. junctional rhythm
  4. 4. QTc = 0.49 s
  5. 5. dual-chamber (AV) paced rhythm
  6. 6. torsades de pointes

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