ECG Education

ECG Education: Back to Basics

When Editor, Tim Larner, asked me if I would like to become involved in the Cardiology HD publication, one of the plans we had for the educational development of readers was to strip the ECG back to basics.

The ECG quiz is very popular, but it somewhat excludes readers that aren’t really sure quite how to go about reading the ECG in the first place. Often we know how to do something, but fall a little bit short of the understanding of why we are doing it – and even more importantly sometimes when we relearn how to do something we discover our practice wasn’t quite as good as we thought it was in the first place.

Over the forthcoming publications we want to stop the ECG machine, put the electrodes back in the packet and start the process over – from the very beginning. I aim to explain how the ECG is properly performed, why, and how to read the ECG itself in a step by step way. Like any other cardiology test or procedure, by taking a methodical approach in the way it is performed and understood, should give you the opportunity to self-assess and improve your practice.

This publication is predominantly read by cardiology staff, and no doubt there are many of you who will think that this is a training tool a bit below your expertise.

So, you may be interested to learn that there was a paper published in the International Journal of Clinical Practice in 2008 that observed the accuracy of ECG electrode placement of 120 clinical staff. The subjects comprised of physicians, nurses and cardiac physiologists involved in the clinical assessment and care of patients with suspected cardiac disease. The group were asked to complete a questionnaire and mark on two diagrams of the chest wall the positions they would place precordial electrodes V1–V6. The study showed wide inter-individual and inter-group variations in the placement of electrodes.

Notably, V1 and V2 were frequently incorrectly positioned in the second intercostal space, especially by physicians.

The correct position of V1 in the fourth right intercostal space was identified by 90% of cardiac physiologists, 49% of nurses, 31% of physicians (excluding cardiologists) and – most disappointing of all – only 16% of cardiologists (p < 0.001 for inter-group differences).

V5 and V6 were also often incorrectly positioned too high on the lateral chest wall.

Incorrect positioning of the precordial electrodes changes the ECG significantly elevating the risk of misdiagnosis that can result in unnecessary treatment. Equally, doctors who are aware of the possibility of lead misplacement may be inclined to ignore some ECG changes that may be genuine evidence of ischaemia. It was concluded that the only safe solution is proper precordial electrode placement, which requires training and an environment supporting precision.

We hope to offer you some of the tools that you require to ensure you have access to accurate and useful documents and training information. I would recommend you start by reading this article1 and the Society of Cardiological Science and Technology ‘Consensus Guidelines on performing a 12-lead resting ECG’ which you can find at www.scst.org.uk.

References

  1. Rajaganeshan R, Ludlam C.L, Francis D.P, Parasramka S.V, Sutton R. Int J Clin Pract, 2008, 62; 1: 65–70.

Author:

Sophie Blackman
Head of Clinical Physiology
West Hertfordshire NHS Trust
UK

Facebook Comments