Right & Left Atrial Enlargement

How can you tell the difference between a left versus right atrial enlargement pattern on EKG? This is a mnemonic on how I remember it. Lead 2 is the best place to look at these two patterns. Remember lead 2 for double the size of the atrium. Let's start with the left atrial enlargement, or LAE. Again, let's look at lead 2 and we see a double humped widened P wave greater than three little boxes across. The letters LAE. Remind me of the word laying down across the bed as you sleep. Notice the young boy here in this picture laying across his bed to sleep with 3 small boxes underneath his bed. Notice the quilt as the young boy sleeps with the double hump camel to remind you of the widened double hump P wave found in lead 2. You could also look at V1 & the sinusoidal pattern with the downward deflection of 1 little box across & 1 little box down. Next, let's look at right atrial enlargement, or RAE. Notice now the boy raising up from bed and that is raise up for RAE, mimicking lead 2 here as the P wave is raised up with 2 & a half little boxes in amplitude found there for RAE. Looking at V1 shows an initial amplifjcation at the beginning phase of the O wave as well. So in sum, that is the EKG patterns of right & left atrial enlargement. Laying down across bed for LAE & raising up from bed for RAE.