If you'd like to support us and get something great in return, check out our OSCE Checklist Booklet containing over 150 OSCE checklists in PDF format. You might also be interested in our Clinical Skills App and our OSCE Flashcard Collection which contains over 2000 cards.


Once on the ward, you’ll be asked to comment on ECGs regularly, therefore it’s really important to understand how to read an ECGย effectively.ย If you want to learn more about ECGs, you can check out ourย ECG guides.

Take ourย ECG quiz to put your knowledge to the test.

Check out our brand new FREE quiz platform, with over 2000 MCQs at geekyquiz.com

ECG quiz

Congratulations - you have completed ECG quiz. You scored %%SCORE%% out of %%TOTAL%%. Your performance has been rated as %%RATING%%
Your answers are highlighted below.
Question 1
If ST-elevation was noted in leads II, III and aVF, what would it suggest?
A
An anterior myocardial infarction
B
A posterior myocardial infarction
C
A septal myocardial infarction
D
An inferior myocardial infarction
Question 1 Explanation: 
Leads II, III and aVF all view the heart in the inferior plane. ST-elevation in only these leads would be suggestive of an inferior myocardial infarction.
Question 2
Which of the following best describes the ECG leads shown below?
A
Right axis deviation
B
Left axis deviation
Question 3
What is the duration of a normal PR-interval?
A
0.08 - 0.12 seconds (2-3 small squares)
B
0.12 - 0.2 seconds (3-5 small squares)
C
0.04 - 0.08 seconds (1-2 small squares)
D
0.04 - 0.12 seconds (1-3 small squares)
Question 3 Explanation: 
In healthy individuals, the PR-interval is between 0.12-0.2 seconds. A PR interval longer than 0.2 seconds suggests the presence of heart block. A short PR-interval may suggest the presence of an accessory pathway between the atria and ventricles (e.g. WPW syndrome).
Question 4
A patient is noted to have an abnormally shortened PR-interval on their ECG. Which of the following is the most likely cause?
A
Right bundle branch block
B
Left bundle branch block
C
Wolff-Parkinson-White (WPW) syndrome
D
Atrioventricular nodal fibrosis
Question 4 Explanation: 
A short PR-interval indicates abnormally short conduction time between the atria and ventricles. This is typically caused by the presence of an accessory pathway between the atria and ventricles. WPW syndrome is an example of this kind of disorder. In WPW syndrome, an accessory pathway known as the bundle of Kent is present. Most individuals are asymptomatic, however, there is a risk of sudden death without treatment.
Question 5
What does ST-elevation suggest?
A
Myocardial infarction
B
Heart murmur
C
Heart block - Mobitz type II
D
Bundle branch block
Question 6
What view of the heart do leads I, aVL, V5 and V6 represent?
A
Anterior
B
Septal
C
Inferior
D
Lateral
Question 7
What view of the heart do leads V3 and V4 represent?
A
Anterior
B
Inferior
C
Lateral
D
Septal
Question 8
If there were 3 large squares in an R-R interval what would the heart rate be?
A
70 bpm
B
80 bpm
C
100 bpm
D
90 bpm
Question 8 Explanation: 
To calculate heart rate from an ECG you can count the number of large squares in an R-R interval then divide 300 by this number. Therefore 300/3 = 100 bpm.
Question 9
An ECG is performed and reveals a progressively increasing PR interval and dropping of QRS complexes at regular intervals. Which of the following is the most likely diagnosis?
A
First-degree heart block
B
Second-degree heart block (Mobitz type 2)
C
Hyperkalaemia
D
Second-degree heart block (Mobitz type 1)
Question 9 Explanation: 
Second-degree heart block (Mobitz type 1) is a disease of the atrioventricular node. Typical ECG findings include progressive prolongation of the PR-interval with associated regular dropping of QRS complexes.
Question 10
What view of the heart do leads II, III and aVF represent?
A
Septal
B
Lateral
C
Anterior
D
Inferior
Question 11
What would it suggest if lead I became more positive than lead II and lead III became negative?
A
Right axis deviation
B
Left axis deviation
Question 12
Which artery is most likely to be affected in the context of ST elevation being present in leads V3 and V4?
A
Left anterior descending coronary artery
B
Left circumflex coronary artery
C
All of the above
D
Right coronary artery
Question 12 Explanation: 
Leads V3 and V4 represent the anterior portion of the heart. ST elevation in these leads would be suggestive of anterior myocardial infarction. The anterior portion of the heart is supplied primarily by the left anterior descending artery.
Question 13
An ECG reveals an absence of P-waves and an irregular rhythm. Which of the following is the most likely diagnosis?
A
1st-degree heart block
B
Atrial fibrillation
C
2nd-degree heart block
D
Ventricular tachycardia
Question 13 Explanation: 
In atrial fibrillation, the atria no longer conduct electricity from the sinoatrial node in an orderly fashion. As a result, P-waves are lost. As a result of disordered atrial activity, only occasional waves of depolarisation pass through to the atrioventricular node and cause ventricular activation. This causes the typical irregular rhythm.
Question 14
What is the normal duration of a QRS complex?
A
0.12 seconds (3 small squares)
B
0.16 seconds (4 small squares)
C
0.04 seconds (1 small square)
D
0.08 seconds (2 small squares)
Question 14 Explanation: 
In most healthy individuals, you would expect QRS complexes to be around 0.12 seconds in duration. If a QRS complex lasts longer it is described as a "wide QRS" and indicates inefficient conduction ventricular conduction (e.g. bundle branch block).
Question 15
What is the most common cause of left axis deviation?
A
Left ventricular hypertrophy
B
Right ventricular hypertrophy
C
Defects of the conduction system
D
Atrial septal defects
Question 15 Explanation: 
Left axis deviation is rarely the result of left ventricular hypertrophy and more often due to defects in the conduction system of the heart.
Question 16
What view of the heart do leads V1 and V2 represent?
A
Anterior
B
Lateral
C
Inferior
D
Septal
Question 17
Which of the following is a common cause of right axis deviation?
A
Ventricular septal defect
B
Left ventricular hypertrophy
C
Atrial septal defect
D
Right ventricular hypertrophy
Question 17 Explanation: 
In right ventricular hypertrophy, the increased muscle mass of the right ventricle causes an increased signal on the ECG. As a result, the axis of the heart is shifted to the right with lead III becoming more positive and lead I and II becoming less positive.
Once you are finished, click the button below. Any items you have not completed will be marked incorrect. Get Results
There are 17 questions to complete.

ย 

 

Print Friendly, PDF & Email