Chest pain, among other symptoms. What do you see?

 This patient had many complaints including chest pain.

The computer called this ***Acute STEMI***

What do you think?

STEMI never has a very short QT.  This QT interval is 320 ms, with a QTc of around 350, depending on which correction formula you use.  (There is Bazett, Fridericia, Hodges, Framingham and Rautaharju -- see here at mdcalc: https://www.mdcalc.com/calc/48/corrected-qt-interval-qtc

If the ST Elevation here were due to STEMI, it would be an LAD Occlusion.  You can use my LAD Occlusion/Normal Variant STE formula on this.  I did, and the result was the lowest value I have ever obtained (10.4).  It is virtually impossible to have an LAD Occlusion with such a low formula value.  

It is the short QT which drives that value down.  

When the QT is very short, there are 2 important diagnoses to consider:

1. Short QT syndrome.  This causes deadly arrhythmias and should be considered in patients with syncope and short QT

2. Hypercalcemia.

I sent this to Jesse McLaren (@ECGCases) and he immediately responded "Hypercalcemia?"

The ioninzed calcium was 6.5 mEq/L (very high).

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Comment by KEN GRAUER, MD (2/17/2023):

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Today’s case is from a patient with “many complaints”, including chest pain — and, an ECG that raised concern about acute anterior OMI. As per Dr. Smith — there are 2 pieces of “good news” regarding this case. These are:

• On careful review — the patient’s initial ECG is not suggestive of acute OMI.
• Instead of OMI — the initial ECG strongly is strongly suggestive of hypercalcemia.

The “beauty” of today’s case — is being able to quickly discount acute OMI from likely diagnostic consideration — and — being able to diagnose a metabolic condition from an ECG.

• For clarity in Figure-1 — I’ve labeled today’s initial tracing.

Figure-1: I’ve labeled the initial tracing in today’s case.

Why Acute OMI is Unlikely:

As per Dr. Smith — the QTc of the ECG in Figure-1 is 350 msec. This is an extremely short QTc value.

• The QTc is usually increased with acute OMI. Although the QTc can sometimes be normal with OMI — it should not be short (See below from more on specific QTc interval durations).
• Although there is ST segment coving with some J-point ST elevation in anterior leads V1-thru-V3 — the shape of these ST-T waves does not “look like” acute OMI. Instead — the shape of ST-T waves is unusual for OMI, in that the peak of the T wave occurs early! (See below for more on the timing of T wave peaking). 
• Instead the localization of ST-T wave findings (as typically is seen with acute OMI) — the shape of ST-T waves in ECG #1 looks similar in 10/12 leads (ie, upright ST-T wave with ST takeoff straightening and short T wave peak time).

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As per Dr. Smith — The differential diagnosis for today’s tracing, with its short QTc ~350 msec. is: i) SQTS (Short QT Syndrome); and, ii) Hypercalcemia.

Features of Short QT Syndrome:

From My Comment at the bottom of the page in the September 2, 2019 post of Dr. Smith’s ECG Blog:

• SQTS is an inherited cardiac channelopathy determined by the presence of symptoms (syncope, cardiac arrest) — positive family history — and the ECG finding of an abnormally short QTc interval.
• SQTS is a relatively new diagnosis that has only been recognized as a distinct clinical entity since 2000. The disorder is rare — but it takes on importance as a potential cause of atrial and ventricular arrhythmias, including cardiac arrest. Treatment is by ICD (implantable cardioverter defibrillator).
• Males with a QTc ≤330 ms — and females with a QTc ≤340 ms are defined as having SQTS, even if they are asymptomatic.
• Males with a QTc ≤360 ms — and females with a QTc ≤370 ms are said to have a “short” QTc. Such patients may have SQTS if, in addition to the "short" QTc — there is a history of cardiac arrest, unexplained syncope or atrial fibrillation at an early age.
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• Regarding Today’s Case: We were not told the age or sex of today’s patient. As can be seen from the above cited QTc intervals — this demographic information is relevant to today’s case! That said — the QTc estimated for today's patient = 350 msec., which places the patient (regardless if male or female) — into the classification of a “short” QTc (but not quite short enough to qualify for SQTC). Assuming there was no history of cardiac arrest, unexplained syncope or AFib at an early age — cardiac risk from a “short” QTc is clearly less than for patients with frank SQTC.

The ECG Diagnosis of Hypercalcemia:

From My Comment at the bottom of the page in the October 30, 2020 post of Dr. Smith’s ECG Blog:

• While the textbook description of ECG findings of hypercalcemia is often limited to “QT interval shortening” — QT shortening is not an easy ECG finding to recognize (even when you are looking for it!). In addition, what is not described in textbooks — is how high the serum Ca++ must go before such QT interval shortening occurs. As Family Medicine Attending (working in and out of the hospital) — I religiously scrutinized the ECGs of all patients I encountered in whom serum calcium levels were elevated. In my experience — NO change in ECG appearance was noted in the overwhelming majority of hypercalcemic patients until their serum Ca++ level was significantly elevated (ie, a total calcium level over 12 mg/dL). KEY Point: — Do not expect to pick up hypercalcemia on ECG unless serum Ca++ is increased by a lot. (The ionized serum calcium level of 6.5 mEq/L in today’s case clearly qualifies as sufficiently elevated to produce ECG changes).
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• PEARL: More than simply QT interval “shortening” — the principal ECG finding of significant hypercalcemia is a short-Q-to-peak-of-T interval. By this I mean that the time it takes for the T wave to attain its peak is shortened with significant hypercalcemia. I know of no measurement to quantify this shortened time-until-T-wave-peak. Instead — it is a subjective judgment — that with experience (armed by an increased index of suspicion for the case-at-hand) YOU can learn to appreciate.
• Regarding ECG #1 — I chose the lead with the most ST-T wave deviation ( = lead V2 in Figure-1) to draw in 2 vertical BLUE lines highlighting the point where I thought definite “peaking of the T wave" is seen. Subjectively — Doesn’t the time until attaining this T wave peak seem short? (with respect to the vertical RED line that marks the end of the T wave in this lead).

The Importance of the History in Today’s Case:

Hypercalcemia to at least a moderate degree (ie, serum calcium level >12 mg/dL) is not a common diagnosis in an unselected ED population.

• Although there is a fairly long list of potential causes of Hypercalcemia — more than 90% of these patients will have either primary hyperparathyroidism or malignancy. (The relative percentage of patients with hypercalcemia from malignancy — will clearly be much higher in an oncology population).
• This is where the History in today’s case comes in. Depending on the age and sex of today’s patient, as well as additional historical details — the likelihood of malignancy vs a non-lifethreatening cause of hypercalcemia will be greatly influenced. The cause of hypercalcemia needs to be found.
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• Final Speculation: We are told that today’s patient presented with “many complaints”. Chest pain was just one of these complaints. Significant hypercalcemia is notorious for its potential to produce symptoms affecting multiple body systems — hence the saying “Stones/Bones plus Abdominal and Psychic Groans with Cardiac Tones”. Among body systems that may be affected by significant hypercalcemia are GI (abdominal pain; nausea, vomiting; constipation) — Renal (kidney stones; inceased thirst; frequent urination) — Bones and muscles (bone pain; muscle weakness) — Cardiac (chest discomfort; palpitations from induced arrhythmias) — and Psychologic (depression or other psychologic disorders; lethargy; fatigue and/or confusion). THEREFORE: — Perhaps the ED presentation of “many complaints” was the patient’s genuine expression of multi-organ symptoms from the marked hypercalcemia!