EKG of the Week 2018 11-4

This EKG comes courtesy of Dr. Majlesi.

An 81 y/o male presents to the ED complaining of generalized weakness, difficulty speaking and shuffling gait. He has no chest pain or SOB. His vital signs are normal.

His EKG is below.

2018 11-4.jpg

1.       What are the findings on this EKG?

2.       What can explain these findings?


The EKG shows an extreme right axis deviation with negative complexes in leads I and II and positive complexes in lead aVR. 

Several things can cause these findings including COPD, limb lead reversal and dextrocardia. In this case, the patient was found to have situs inversus.


In a normal EKG, the P waves in leads I and II should be upright and the P waves in lead aVR should be inverted. This EKG shows the opposite - negative complexes with inverted P waves in leads I and II and positive complexes and upright P waves in lead aVR.

This pattern can be seen in severe COPD or in limb lead reversal (if the right arm lead is placed on the left arm and the left arm lead is placed on the right arm). However in that scenario, the precordial leads should be normal. In our EKG, the R wave progression in the precordial leads is reversed. The QRS complex is positive in lead V1 and negative in lead V6. This occurs because the entire heart is reversed.

Our patient’s Chest X-ray is below.

2018 11-4 CXR.jpg

As you can see, the heart is reversed and on the right side of the body. Additionally, you can see the liver on the left side and the stomach bubble on the right side. This represents complete situs inversus. This is why the patient’s EKG is essentially reversed.