A 60 year old with chest pain

A 60 year old with chest pain:

what do you think?

The medics came to me worried about hyperacute T-waves.  But these are not HATW and I immediately said so.  Why?

The ST segment is too flat, resulting in a narrow base for the T-wave even though the QT interval is quite long (QTc Hodges = 464 and a lot longer by Bazett).  

T-wave hyperacuteness is due to area under the curve, which is height + width + straightness of the ST segment.  The width of the T-wave is not determined only by the QT interval!  It is also determined by the ST segment itself.  A patient with hypocalcemia has a long ST segment and thus long QT, but not necessarily and wide T-wave.

And here we see a long QT without a wide based T-wave; rather, it has a narrow base.

HyperKalemia also has a narrow base.  Is this hyperK.  No.  Although there could be a high K, there is no evidence of it on the ECG because the T-wave is rounded at the top.  You could sit on it without puncturing your behind.

The patient ruled out for MI by troponins.  Potassium was normal.

I sent this ECG to the Queen of Hearts (PMcardio OMI), and here is the verdict:

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MY Comment, by KEN GRAUER, MD (7/10/2023):

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Ruling out acute OMI in a patient with chest pain can be equally challenging as ruling it in. Today's case spotlights this challenge.

• While I was not 100% certain (given the history of chest pain) — that today's ECG might not represent an early stage of an acute event — I suspected that nothing acute was ongoing. 
• The single lead of most concern to me was lead V3 — because there does appear to be an initial small Q wave in this lead — and the ST-T wave in lead V3 is disproportionate to the very small QRS complex in this lead.

That said — the reasons I suspected nothing acute was ongoing were the following:

• Small and narrow q waves are present in multiple leads — include leads I, II, III, aVF; and V3-V6. A notched rsR' complex is seen in lead aVL — which in the context of 8 other leads with real q waves, I viewed as a small & narrow q-wave "equivalent". Bottom Line — While I could not rule out the possibility that some of these q waves might reflect prior infarction — they might just as easily represent an insignificant variant in a patient who has no prior history of infarction.
• Somewhat "bulky" upright T waves which (as per Dr. Smith) lack a wide base — are seen in no less than 8/12 leads (ie, in leads I,II,III,aVF; and in V4,V5,V6) — as well as in the V3 lead that I was concerned about. Bottom Line — The presence of "bulky" upright T waves in today's tracing is a generalized finding — whereas with OMI, acute ST-T wave changes tend to localize.
• A mirror-image opposite "bulky" inverted T wave is seen in right-sided leads aVR and V1 — whereas I would not have expected that if there was an ongoing acute OMI.
• Finally — I believe there is a reasonable explanation why the T wave in lead V3 looks disproportionate — namely, that both leads V2 and V3 represent "transition leads" — as the QRS evolves from predominantly negative (as it is in lead V1) to predominantly positive (as it is in leads V4,V5,V6). Similarly — the ST-T wave also "transitions" from "bulky negativity" (as is seen in lead V1) — to "bulky positivity" (was we see in leads V3-thru-V6). 
• PEARL: In my experience, when transition lead(s) are seen — the "zone" of transition for the QRS complex is not necessarily the same as for the ST-T wave (ie, In today's case — the T wave becomes predominantly positive between V2-to-V3 — whereas the QRS becomes predominantly positive a little bit later, between V3-to-V4).

My BOTTOM LINE in Today's Case:

I was admittedly not 100% certain that today's ECG might not represent an acute event. As a result — I'm glad that serum K+ was verified as normal — and that serial troponins formally ruled out an acute event. BUT — I felt as a single ECG — that the odds against acute OMI for today's tracing were >90% for all of the above-stated reasons.