Dextrocardia and Reversed Limb Leads

In the previous ECG presentation, we learnt how to recognise reversed arm leads. Here is a summary:

Lead I is flipped and leads aVR and aVL are reversed. This same scenario occurs with dextrocardia, where the leads are not reversed, but rather the heart is positioned with the apex of the left ventricle on the right side.

‍Here is an ECG from a patient with dextrocardia:

With dextrocardia the chest leads are very different.

Leads V1 and V2 are reversed and leads V3 to V6 appear as they would, if the leads were placed on the right side (V3R to V6R) in a normal patient.

Here is another example of dextrocardia:

Now let us change the arm leads (no need to swap the leg leads) and place the chest leads on the right.

Presto; We have a near-normal looking ECG.

I have seen an inexperienced technician place the leads on the right side of the chest, but the limb leads normal!

The ECG reporter can often get confused, when the chest leads are inadvertently reversed, but on the left side of the chest. I have seen this reported as dextrocardia.

Here is an example:

Finally, the pièce de résistance!

I call this the “full hand” and I have seen it several times. There are reversed arm and chest (on the left side) leads. Remember, keep your eyes open when reporting ECGs!

‍

Harry Mond