Friday, January 14, 2022

Would your radiologist make this diagnosis, or should you record an ECG in trauma?

A very young man had severe blunt trauma with severe head injury.

As part of his evaluation, he had a "pan-scan" which of course includes a chest abdomen pelvis CT.

Here is one slice of his chest:

What do you see?


Let's look at a closer view, and also made easier to see using Spectral CT:


And one more:


The very dark area at the septum and the apex of both ventricles is transmural ischemia.  There is no contrast making it into this area which should be perfused by the LAD.


Here is a color image of the same:


Notice the extremely dark area at the apex and apical part of the septum.



The radiologist was Dr. Gopal Punjabi, who is quite a wizard, and frequently diagnoses acute MI on CT scan of the chest.  He immediately saw this and notified the clinicians.

Because of this CT interpretation, they recorded an ECG:

It is clear that this transmural ischemia (STEMI/OMI) could have been diagnosed earlier with an ECG.

The ECG is all but diagnostic of LAD occlusion (Occlusion MI, or OMI)


This is almost certainly due to LAD Occlusion MI.  It is conceivable that one might see the same with a very severe myocardial contusion.  However, the CT confirms that there is no blood flow to the affected myocardium.  

One might consider takotsubo, but this would be a very unusual ECG for takotsubo because the ST elevation is focal to one coronary distribution.

There was only one initial troponin measured.  It was 73 ng/L (URL = 34 ng/L for men).

Because of severe head injury, the patient was declared brain dead, and no further troponins nor angiogram nor formal echocardiogram were done.  

Probable diagnosis: contusion and dissection of LAD

I looked back at the cardiac portion of the FAST exam and there was one view available.  (Sorry for the poor quality -- I could not download it and so just used my phone to take a video of the screen)  

It clearly shows apical wall motion abnormality.

By echo alone, we might think this is apical ballooning of takotsubo.  But the ECG is not at all typical for takotsubo. 

I cannot say with certainty that takotsubo would not show the same cardiac CT findings, but I doubt it.  It would be unlikely to show those ECG findings, as explained above.


This is all I could find on the topic of CT myocardial enhancement in takotsubo (one case report): Sueta D et al. Comprehensive assessment of takotsubo cardiomyopathy by cardiac computed tomography.  Emerg Radiol 2019;26(1):109–12. Available from: http://dx.doi.org/10.1007/s10140-018-1610-2


Learning Points:

1. Recording an ECG on a blunt trauma patient can be critical.  In this case, it did not changed the management, but only because of severe head injury.  It might have made an enormous difference.

2. Also, if the ECG is abnormal, pay attention to it!!  See this case:

A Child with Blunt Trauma




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Brief Comment by KEN GRAUER, MD (1/14/2022):

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Interesting case for this unfortunate young man who died from his severe head injury. The initial ECG in today's case (which I have reproduced in Figure-1) is markedly abnormal — with profound, coved ST elevation in not only the anterior leads — but also high lateral leads I and aVL + mirror-image opposite inferior lead ST depression (to the aVL ST elevation+ marked right axis (consistent with LPHB+ and not only loss of anterior R waves, but a fragmented downslope to the S wave in lead V3 (often itself a sign that there has been anterior infarction).


Dr. Smith lists 2 potential reasons to explain these ECG findings: i) Acute LAD occlusion; and, ii) Based on Echo findings — Takotsubo cardiomyopathy.


I would add a 3rd potential contributing factor = severe CNS injury — which is notorious for causing QTc prolongation with often unpredictable ST-T wave abnormalities that often result in “pseudo-infarct” patterns.


Obviously — severe CNS injury is not the only cause of ECG abnormalities in today’s case given marked Spectral CT and Echo abnormalities — but I thought the shape of elevated and depressed ST-T waves on today’s initial ECG to be distinctly unusual in the degree of T wave “fattening” (rounding out) at T wave peak and/or nadir (in those leads where the ST is depressed). I thought at least a portion of the unusual ECG findings in Figure-1 may be attributable to severe CNS injury.



Additional Learning Point:

  • CNS catastrophes (ie, stroke, bleed, trauma, tumor, coma, seizure, etc.) — are notorious for sometimes producing bizarre ECG findings (QTc prolongation, marked ST-T wave abnormalities that are impossible to predict, "pseudo-infarct" patterns).


Figure-1: The initial ECG in today's case — obtained from a young man with severe blunt trauma with severe head injury (See text).








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