A 41-year-old male who presents to the emergency department with chest pain. Patient reports approximately 2 hours prior to arrival he developed a sharp chest pain that radiates into his left arm and left lower leg. Describes the radiating pain as numbness/tingling. No shortness of breath. No recent travel. No cough. No cardiac history.
Here is his ECG:
He had a previous ECG on file, from many years prior:
There is new T-wave inversion in inferior leads and V3-V6. This is recorded during pain. The faculty physician thought this is highly likely to be ACS.
However, most T-wave inversion during pain is nonspecific. T-wave inversion AFTER resolution of anginal type pain is highly likely to be due to reperfusion.
On occasion, unstable angina can present with reversible T-wave inversion during pain. When the ischemia is resolved, if there is no infarction, the T-wave can normalize. This is in contrast to Wellens' syndrome, which involves at least a small amount of infarction (troponin elevation) and in which the T-wave inversion evolves into deeper and deeper T-wave inversion.
See these 2 contrasting cases:
Classic Evolution of Wellens' T-waves over 26 hours
Dynamic, Reversible, Ischemic T-wave inversion mimics Wellens'. All trops negative.
This case directly above was not in the era of high sensitivity troponin. Unstable angina in the era of hs trop still exists. I have never seen it with undetectable hs trops, but acute MI is possible after a single initial hs trop below the limit of detection.
In our study of a single initial hs troponin I below the limit of detection (1.9 ng/L, Abbott Architect), the NPV and sensitivity for acute MI was not 100%, rather 99.6% and 98.8%. In other words, it is possible for a subsequent troponin to be elevated above the 99% URL when the first one is undetectable, but is very uncommon. I do not think it is possible for a 2nd trop to remain undetectable in a patient then goes on to rule in for acute MI, unless there is a 2nd event.
I know of no data on unstable angina/30-day adverse events/acute MI after 2 serial undetectable trops. Unstable angina would be exceedingly rare in such a situation, but still possible. Acute MI would not be possible unless there was another event.
Back to this case:
These T-wave inversions do not look ischemic to me. They look very nonspecific. When I see a case like this, I am skeptical that the ECG is manifesting acute ischemia or reperfused OMI. Unless the patient on history and exam clearly looks like he/she is having an acute MI, I am satisfied to wait for the troponin.
Here is the Queen's interpretation:
She explains here:
Outcome:
All hs troponin I ﹤ 3 ng/L (undetectable). There was no repeat ECG. Again, although T-waves can reversibly invert with unstable angina, unstable angina with 2 high sensitivity trops below the limit of detection could possibly occur, but is extremely unlikely.
My impression was correct and so was the Queen's: this is NOT ischemic T-wave inversion.
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