What Do You Think 32

Asymptomatic 54-year old international commercial pilot.

Annual routine ECG – suggests previous septal infarct.

Normal coronary angiogram, but dense embolic stroke during procedure with permanent right hemiplegia.

‍

What do you think?

‍

Leads V1 and V2 are reversed and when placed in their correct position, the ECG is normal; V1 red highlight and V2 yellow highlight.

ECG lead malposition is not uncommon and frequently missed or incorrectly diagnosed with potential serious consequences. As the ECG cables age, the identification of the leads becomes more difficult to read, particularly under poor light. Before printing the recorded tracing, it is important to check the leads and the ECG.

Identification of lead malposition may be subtle.

This is another V1-V2 error, which was reported as normal.

This one took some working out, but there is a pattern to the way the leads are positioned. The ECG could have been reported as a previous lateral (Q V5, V6, red highlight) and posterior (R inV1, yellow highlight) myocardial infarction, particularly as there is also a previous inferior myocardial infarction (Q II, III, aVF, blue highlight).

Then there are those that are completely haphazard,

or completely reversed.

When corrected, the chest leads are normal.

Another malposition is lead placement on the right side in an otherwise normal patient.

Leads V1 and V2 are reversed(red highlight), and the remaining chest leads are  small voltages on the right side of the chest away from the heart (yellow highlight).

This chest lead malposition (red highlight) can be coupled to reversed arm leads (yellow highlight) to create a very abnormal ECG.

Remember with reversed arm leads; lead I is flipped, leads aVR and aVL are reversed as are leads II and III.

The corrected ECG:

I call this “the full hand” and have seen it a number of times.

The arm leads are reversed (red highlight) as are the chest leads (yellow highlight).

This ECG was reported as dextrocardia. Remember, with dextrocardia the chest leads are not reversed, but are on the right side of the chest with reducing voltages from V3 to V6.

Dextrocardia: The arm leads are reversed (red highlight) and the chest leads are positioned on the wrong side with decreasing voltages (yellow highlight).

Harry Mond