I was reading ECGs on the system when I saw this one (ECG-1):
My read was "ST Elevation that is NOT ischemic".
I suspected this strongly because it just doesn't "look right" for a STEMI, in spite of the clear STE in V3 and V4. This STE appears to be due to LVH, even though the STE in V4 is concordant to the QRS.
There were previous ECGs for comparison, so I looked at them:
The patient had presented 4 days earlier with chest pain and had several ECGs recorded:
Time zero (ECG-2):
There were previous ones to compare to at that time:
This is from 13 days prior (ECG-3):
This is from 3 years prior (ECG-4):
So serial ECGs were recorded on that presentation 3 days prior:
Time 17 min (ECG-5):
Time 100 min (ECG:-6)
There was a bedside echo. Here is the parasternal short axis:
This shows severe concentric LVH
Next AM (ECG-7)
On that previous visit, he had been diagnosed with NSTEMI based on hs troponins of 82 ng/L, then 97 ng/L, then 80 ng/L. But he had always in the past had slightly elevated troponins.
He did have an abnormal echo:
Normal left ventricular size, severely increased wall thickness. (i.e, LVH)
Moderately reduced systolic function; estimated LVEF 30-35%.
Regional wall motion abnormality-anterior, probable
So chronically elevated troponins are probably due to severe LVH.
But his angiogram was normal (a normal angiogram does NOT rule out ACS or even OMI at the time of the ECG)
On the presentation of ECG-1, he also had elevated trops with a rise and fall (92, 124, 69)
So is this a type 1 MI OMI, type 1 NOMI, or type 2 MI?
My opinion, and also that of the treating cardiologists: the ECG findings are NOT due to any OMI at any time. They are due to a combination of LVH, benign ST Elevation, and benign T-wave inversion.
The troponin elevations are due either type 1 Non-OMI or type 2 MI.
What is certain is this: all of these ECGs are compatible with a non-ischemic etiology, and you should remember the morphology and suspect that it may be non-ischemic when you see it.
Learning Points:
ECGs are very hard. They require years of training, paying attention, recognizing patterns. There are few easy paths to expertise.
But some takeaways are that, when there is doubt:
1. Look for old ECGs
2. Do serial ECGs
3. Use bedside and formal echo
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