EKG of the Week – Week 25 ANSWERS

Hey Guys,

    STEMI or NO STEMI:  NO STEMI (the limb leads are reversed, take a look!)
As for the rest of the EKGs, remember, any time a patient presents with syncope, you need to get an ekg.  I always check for:

H – HOCM https://lifeinthefastlane.com/ecg-library/hcm/

E– Epsilon Wave (ARVD – Arrythrmogenic Right Ventricular Dysplasia) – https://lifeinthefastlane.com/ecg-library/basics/arrhythmogenic-right-ventricular-cardiomyopathy/

B – Brugada – https://lifeinthefastlane.com/ecg-library/brugada-syndrome/

@ AV Nodal blocks (see below)

D – Delta Wave (Wolff-Parkinson-White) – https://lifeinthefastlane.com/ecg-library/pre-excitation-syndromes/

Q – Prolonged QT Interval – https://lifeinthefastlane.com/ecg-library/pre-excitation-syndromes/
So what are our concerns with this EKG?  An AV Nodal Block.  Let’s review those quickly:

First Degree AV Block is a PR interval >200 msec (remember, that’s 5 small blocks)
Here’s an example from Life in the Fast Lane:

Second degree, Mobitz type 1 AKA Wenckeback: 
 Progressive prolongment of the PR Interval, eventually leading to a dropped beat.  Remember, the PR interval is longest just before the beat gets dropped and shortest in the conducting beat immediately after the dropped beat.
The P-P interval is generally conserved
Notice how the interval gradually stretches out and then the beat drops:

Second Degree, Mobitz type 2:
No warning!  The PR interval is consistent throughout the EKG and then suddenly, a beat is just dropped.  This is usually due to DAMAGE to the CONDUCTING SYSTEM.  Type 2 is significantly more likely to be associated with hemodynamic compromise and degradation into complete heart block than type 1. 

Third Degree (Complete heart block):
     No association between the P waves and the QRS complexes.  Do not send these patients home.  They need admission for a pacemaker.

So what was going on with our patient’s EKG?  Was it second degree type one or type two?  Tough to assess.  It sure looks like the PR interval stretches out, but when we measured it with fake calipers (two marks on the back of a piece of paper) it looked like the PR interval was the same for each, which would be concerning for Mobitz type 2.  We called cards who used real calipers and said that there was subtle prolonging of the PR interval consistent with a Mobtiz type 1 pattern and the patient did not need admission for a pacemaker.  They said (if you look at the EKG) we were seeing sinus beat, sinus beat, sinus beat, prolonged PR interval, dropped beat, which makes it Mobitz Type 1.  He was discharged with PCM follow up.