Is there Terminal QRS Distortion?

 This ECG has ST Elevation in multiple leads.  Is it normal STE?  Or is it ischemic STE?

What do you think?

This ECG is interesting because it mimics TQRSD.  There are no S-waves in V2 and V3.  BUT look at the very prominent J-waves (J point notching)!!  It is several mm high!

This is a normal ECG.

This patient had CO poisoning but did not have myocardial injury or OMI.  In fact, there was no chest pain either.

This is a great demonstration that a normal ECG, if there is no S-wave in V2 and/or V3, the lead without an S-wave MUST have a J-wave in order to be truly normal.

Anterior OMI?  

If you were thinking that this is not anterior OMI because there is no reciprocal ST depression, it is important to remember that half of anterior STEMI do NOT have any reciprocal ST depression. Presence of STD is helpful; absence is not.

Pericarditis?  

If you were thinking that this is pericarditis, that would be possible in the absence of any clinical information.  However, there is zero PR depression which would be VERY unusual in pericarditis.  Furthermore, as we always state, pericarditis is much less common than either OMI or Normal Variant STE, and should only be diagnosed in the presence of VERY SPECIFIC clinical and ECG findings.

For a full explanation of terminal QRS distortion, see this post:

Best Explanation of Terminal QRS Distortion in Diagnosis of Electrocardiographically Subtle LAD Occlusion

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MY Comment, by KEN GRAUER, MD (10/17/2022):

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I found today's case interesting for several reasons.

• I was shown today's tracing without the benefit of any clinical history. This may mimic what sometimes occurs in practice — as many providers are charged with "oversight" of ECGs ordered by others "to be sure that nothing is missed". In such cases — the 1st priority is to ensure that the ECG they are overseeing does not represent an acute cardiac event that may have been overlooked.
• There are some unusual ECG findings in today's tracing (that I labeled in Figure-1). 
• Finally — I thought today's tracing provided excellent illustration of why having a Systematic Approach to ECG interpretation is so important. 

Figure-1: I've labeled the ECG in today's case to highlight leads with ST elevation and J-point notching.

There is No Acute Cardiac Event:

As per Dr. Smith — there is no acute cardiac event in ECG #1. The tracing mimics T-QRS-D (Terminal QRS Distortion) — but the presence of a distinct J-point notch in leads V2 and V3 (BLUE arrows in Figure-1) negates the possibility of T-QRS-D (See My Comment at the bottom of the page in the November 14, 2019 post in Dr. Smith's ECG Blog).

Additional reasons why I thought an acute cardiac event was less likely included the following:

• Despite ST elevation in multiple leads (with respect to the dotted RED lines in Figure-1) — ST-T waves were upsloping and looked remarkably similar in shape in at least 9 leads. In contrast — with acute OMI, there is usually some localization of abnormal ST-T wave findings to an anatomic location.
• There is no reciprocal ST depression.  
• The Q waves that are seen in the infero-lateral leads are tiny (narrow and small in size). These do not have the appearance of infarction Q waves.
• The QTc is normal.
• There is no loss of R wave amplitude.
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• P.S.: Acute pericarditis may produce diffuse ST elevation. That said, as we have emphasized numerous times in Dr. Smith's ECG Blog — acute pericarditis is uncommon (if not rare) — and probably should not be diagnosed unless the clinical history is strongly suggestive and/or a peericardial friction rub is heard. In today's tracing — PR depression is absent — the ST segment/T wave ratio in lead V6 is not increased — and I thought lead V1 looked distinctly unusual for acute pericarditis (For more on the ECG diagnosis of acute pericarditis — See My Comment at the bottom of the page in the December 13, 2019 post in Dr. Smith's ECG Blog).

There are Some Unusual ECG Findings:

There are some striking features in ECG #1 that caught my attention:

• Lead V1 looks like "it doesn't fit". It's hard for me to remember seeing an RS complex in this lead with such a prominent upright T wave. I suspect some technical mishap.
• Transition occurs very early (ie, The QRS complex is already all positive by lead V2). This is distinctly unusual — and makes me wonder about a structural cardiac abnormality, an anatomic variant, or lead misplacement. At the least — it merits comparison with prior tracings and/or repeat ECG.
• ST elevation is present in 10/12 leads! This ST elevation is upsloping — and marked by prominent J-point notching in leads V2 and V3 (several millimeters high — as noted by Dr. Smith).

I review assessment and classification of ECG repolarization patterns in My Comment, at the bottom of the page in the May 23, 2022 post in Dr. Smith's ECG Blog.

• Today's tracing is consistent with "ERP" (Early Repolarization Pattern) — in that there is prominent J-point notching in leads V2,V3 — with suggestion of a "slur" on the downslope of the R wave in the lateral chest leads + ST elevation with prominent T waves, but no significant QRS prolongation.
• While I still suspect that this will turn out to be a benign ECG — I'd reserve that judgment pending verification of: i) A negative family history (ie, of sudden death or significant arrhythmic event); and, ii) A negative personal history (ie, of any worrisome cardiac arrhythmia — or potential cardiac-related syncope/presynope that the patient may have experienced).
• Finally — My intellectual curiosity would love to see a baseline ECG on this patient — and — I'd love to see a repeat ECG after the patient recovered from the CO poisoning that led to his hospitalization.

Use of a “Systematic" Approach to ECG Interpretation:
In my 4+ decades of experience teaching ECG interpretation to medical providers of all specialties and levels of experience — by far, the greatest hindrance that I've seen to achieving expertise is the failure to consistently use a systematic approach.

• All-too-often overlooked — is awareness that the process of ECG interpretation should consist of 2 Steps: i) Descriptive Analysis — in which the clinician routinely works through a "check-list" to assess the tracing for parameters such as Rate, Rhythm, Intervals, Axis, Chamber Enlargement — and Q-R-S-T Changes; and, ii) The Clinical Impression — in which the findings of Descriptive Analysis are considered in light of the clinical situation.
• The tendency — is to skip over the 1st Step — and instead to jump to a clinical impression of the obvious findings without having systematically reviewed the entire tracing.

For Example:

• How would you interpret the ECG in Figure-1 — IF the clinical history was, "an older patient with new-onset chest pain?"
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• What if instead — this ECG was obtained from a patient admitted to the hospital for a non-cardiac problem, "as part of their routine lab assessment?"  

To Emphasize:

• Descriptive Analysis of this patient's ECG stays the same for both patient examples. That is — the rhythm is sinus arrhythmia — with normal intervals and axis, and no chamber enlargement. There is upsloping ST elevation in 10/12 leads — with prominent J-point notching in leads V2,V3.
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• Regarding my Clinical Impression — Although I'd still suspect that ECG #1 did not represent an acute cardiac event (for the reasons I detailed above) — it would be hard to ignore this amount of ST elevation IF the history was new chest pain (at least until the ECG was repeated and a couple of troponins came back normal).

My Learning Points:

• Without regular use of a 2-Step Systematic Approach to ECG interpretation — ECG findings get overlooked.
• With no more than a little practice — using a "system" will not slow down interpretation. On the contrary — interpretation speeds up, because the check-list is "embedded" in memory, and both easy and fast to apply. And — less obvious but still important findings will not be overlooked!