Friday, January 12, 2018

Lecture, updated: Subtle ECG Findings of LAD Occlusion

This was recorded at a lecture I gave at Controversies and Consensus in Emergency Medicine in Northamptom MA.

This newly posted lecture is more up to date than this one which has been up for a while: 
One hour lecture on Subtle ECG Findings of Coronary Occlusion.  However, it is not quite as nicely produced.

As you watch this, remember that these are not missed STEMIs, rather these are missed opportunities to save myocardium!!


  1. Hey Dr Smith
    Outstanding video, thanks for making it available. Hoping you could provide some citations regarding the statement that echo without wall motion abnormality (in absence of chest pain) can still miss ischemia. Have been looking for papers that definitively demonstrate this. I've had several patients whose anginal pain and ECG resolved prior to echo by cards and was given the explanation that normal echos are definitive, even in absence of symptoms, because wall should still remain "stunned" afterwards on echo. Thanks!

    1. Ari:
      1) I've seen it many times, and put many cases up here in the past, in which the ECG shows ischemia, it is brief, there is WMA, then ischemia resolves (STE, whether subtle or not, resolves and chest pain resolves) and WMA goes away.
      2) simple face validity: Given that ischemia is a spectrum, and on one side of the spectrum is absence of ischemia and normal wall motion, and on the other side is full transmural infarction with permanent WMA, there must be intermediate conditions in which the ischemia is brief enough to have either no stunning or very brief stunning.
      If you find some literature on it, let me know.

  2. Great lecture, again. Your teaching over past few years has enhanced my understanding of EKG and ACS exponentially, and has saved a lot of human myocardium already. Thank You!

    Southern Ostrobothnia EMS, Finland

  3. Hi,
    Great Lecture! I was wondering if you knew of a ratio of Twave to R wave amplitude that separated hyperacute Twaves from those of BER?

    1. The mean differences are in this paper I wrote, but we did not find a best cutoff (although I could). the formula is better than this ratio:

      Look at table 2 in this paper:

      TAavg/RAavg ratio early repol = 0.7 (0.4); MI = 3.1 (4.3); difference = 2.5 (1.8 to 3.2)

    2. Thanks, that seems like quite a significant difference...though as the paper suggests this difference is mostly due to R wave difference. So perhaps the rule of thumb of average R wave <5mm in V2-4 that you propose in the lecture would be of similar sens/spec and be easier to eyeball.

    3. Still, more accurate to make the calculation. It is easy to do.


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