Recording a 12 Lead ECG

“An ECG is a tracing of the electrical activity in the heart and allows for either real time feedback of what is happening or for a printed copy to be reviewed in detail. It is a simple and painless observation which can provide a large amount of information to the healthcare provider.

An ECG is often used alongside other tests to help diagnose and monitor conditions affecting the heart.

It can be used to investigate symptoms of a possible heart problem, such as chest pain, palpitations (suddenly noticeable heartbeats), dizziness and shortness of breath.

An ECG can help detect:

arrhythmias – where the heart beats too slowly, too quickly, or irregularly

coronary heart disease – where the heart's blood supply is blocked or interrupted by a build-up of fatty substances

heart attacks – where the supply of blood to the heart is suddenly blocked

cardiomyopathy – where the heart walls become thickened or enlarged

A series of ECGs can also be taken over time to monitor a person already diagnosed with a heart condition or taking medication known to potentially affect the heart.”  NHS Choices (2018)

An ECG is recorded using electrode stickers attached to the patient’s limbs and chest wall in specific locations. The electrode stickers are connected to the ECG monitoring device which may either show the tracing on a screen, as a physical printout or both.

Read the illustrated guide to recording a 12 lead ECG on ClinicalSkills.net here: 

You will need to be logged into ClinicalSkills.net to use these pages: Go to ClinicalSkills.net, click login at the top, enter your user name and password. You must have set up your account to do this. For further information on how to login to your ClinicalSkills.net account please click here: How to Login to ClinicalSkills.net

Recording a 12-lead electrocardiogram (ECG)

For a quick guide to performing an ECG, watch the video here from Geeky Medics...

Click the picture below.

For further knowledge and understanding of ECGs, including an introduction to the basics of how an ECG complex is produced according to what is happening in the heart, please visit the interactive learning resource 'ECG Works' by clicking on the link here: ECG Works 

Click on the button below to navigate to the 'Take a Test' area of ClinicalSkills.net. Please make sure you're logged into ClinicalSkills.net already, otherwise you may not be able to open and take the test. Once you have reached the 'Take a Test' area, select 'Local Tests' and then click on the test called 'Recording a 12-lead Electrocardiogram (ECG)' to begin. You will need to score 80% or more to pass. Make sure you've read the ClinicalSkills.net procedure thoroughly before taking the test as many of the answers will be found within there!

Read the guides below gain the knowledge of interpretation of ECG.

You will need to be logged into ClinicalSkills.net to use these pages: Go to ClinicalSkills.net, click login at the top, enter your user name and password. You must have set up your account to do this. 

Interpreting a 12-lead electrocardiogram (ECG) Part 1: Introduction

Interpreting a 12-lead electrocardiogram (ECG) Part 2: Rhythm interpretation

Interpreting a 12-lead electrocardiogram (ECG) Part 3: Myocardial ischaemia and infarction

The Royal Marsden Manual of Clinical Nursing Procedures is a text giving guidance and information on a wide range of clinical skills and procedures including step by step guidance with associated images and text. 

Royal Marsden Manual of Clinical Procedures (9th Edition): 12 lead ECG- Page 472-478

ProQuest Ebook Central - Reader 

This resource is the Geeky Medics website and contains a step by step guide to recording a 12 lead ECG. This is supported with images and descriptions of the procedure as well as an interactive checklist to support you in ensuring all steps are complete.

Geeky Medics - Recording a 12 Lead ECG OSCE Guide 

If you'd like to look in more detail at ECG recording, including how the different electrode positions produce the ECG and provide different views of the heart and its conduction, please access the interactive cardiology learning resource below from the University of Nottingham, which includes quiz questions, as well as an introduction to normal heart function, sinus rhythm and some common abnormal rhythms and other abnormal changes which might be recorded by an ECG.

University of Nottingham - Cardiology Learning Resource 

Here is another guide to undertaking a 12 lead ECG recording. The Oxford Handbook of Clinical Skills in Adult Nursing give a guide to completing various practical skills which may be encounter through nursing practice. The handbook give a concise run through of each skill and how to perform these. For 12 Lead ECGs please start at page 370. Please note that this is an e-book available via the library and you may need to log in using your SHU login and password.

Oxford Handbook of Clinical Skills in Adult Nursing

Below is an interesting article from the Kansas Journal of Medicine, which outlines the importance of correct ECG electrode placement according to the standard guideline recommendations.  In practice you might find examples of ECGs being incorrectly placed 'by sight'  and other examples of non gold-standard practice, such as placement of wrist and ankle leads on the torso instead. It also describes some useful examples of how incorrect placement can adversely affect the accuracy of the reading obtained, along with some example ECGs. 

Kansas Medical Journal - Electrocardiographic Limb Leads Placement and Its Clinical Implication 

Here is a useful resource that you might wish to signpost patients to in the event of questions or queries about ECG recording - why might it be done? How is it carried out? What different types of ECG might be taken? Plus other useful patient information.

NHS - Having an Electrocardiogram (ECG) 

Date reviewed: October 2022

Next review: October 2023