This is the follow-up discussion to:
Let’s take another look at the 12-lead ECG.
This is a very suspicious ECG and must be considered acute inferior STEMI until proven otherwise.
This was my initial gut feeling about this ECG and I confirmed it with one of the smartest electrocardiographers I know (Stephen Smith, M.D. from Dr. Smith’s ECG Blog).
In fact, he discussed this exact type of ECG in his recent appearance on the EMCrit podcast.
Let’s take another look at the ECG marked up so I can point out the key features that make this ECG so suspicious.
In the first place, the ST-elevation is limited to a particular set of contiguous leads (the inferior leads).
When a patient is experiencing acute inferior ST-elevation myocardial infarction, there is almost ALWAYS some type of reciprocal finding (ST depression, T-wave inversion, or both) in lead aVL.
If this is a mimic of acute STEMI, it’s one of the best I’ve ever seen, because of the inverted T-wave. In fact, I’m certain that’s why the computerized interpretive statement is calling this a STEMI.
In addition, the R/S ratio in lead V1 makes me suspicious (although it would be more suspicious in an older adult).
I’m also not pleased with the appearance of the Q-waves in lead III. Granted, lead III is a bit “quirky” but as you can see, these little coincidences are adding up and as Tomas Garcia M.D. is fond of saying, one must “consider the company” any ECG abnormality keeps.
This case demonstrates why a good story is very important when screening people for acute STEMI.
As Dr. Smith indicated in regard to this case, a lower pre-test probability changes things and makes some type of localized pericarditis much more likely (remember the patient has a low-grade fever).
However, it does not eliminate the possibility of acute inferior STEMI, and an ECG abnormality like this cannot be blown off. The way to handle it is a stat bedside echocardiogram to look for wall motion abnormalities that would indicate acute STEMI.
(Editor’s note: this ECG is not typical for benign early repolarization in spite of the fact that the patient is a young African American male).