Tuesday, May 26, 2015

New 40 minute lecture on T-wave Inversion



T-wave Inversion

 I just found one mistake at minutes 7:00 to 7:30: 

The QRS axis is 90 degrees and the T-wave axis minus 30, for a QRST angle of 120 degrees.


Posted by Steve Smith at 12:41 PM

31 comments:

  1. UnknownMay 30, 2015 at 8:36 PM

    Fantastic lecture. Thank you. Please record more.

    ReplyDelete
    Replies
    1. Steve SmithMay 31, 2015 at 10:54 AM

      Jim,
      Thanks! Please spread the word.
      You can see other lectures posted down the sidebar.
      Steve

      Delete
  2. UnknownJuly 19, 2015 at 3:14 PM

    thanks dr Smith, very interesting and practic information

    ReplyDelete
  3. UnknownSeptember 6, 2015 at 3:54 AM

    I think that QRS axis is +60 and T wave axis is -30 so the difference is 90 ( min 7:00 to 7:30) ? But what is normal range for Axis difference between QRS and T wave and its significance ?

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    Replies
    1. Steve SmithSeptember 6, 2015 at 6:10 AM

      Normal is not easily defined, but as the difference gets larger, the risk gets proportionally larger. > 100 definitely abnormal. My attention is caught if the angle is greater than 60 degrees, but this is not definitely abnormal.

      Delete
    2. UnknownSeptember 12, 2015 at 7:24 AM

      But i know that If QRS-T angle >100 ,It's suspicious for secondary abnormality rather than primary as LVH ,and There is a big chance it’s not a STEMI ?
      So when to consider QRS/T angle abnormal if more than 100 ?

      Delete
  4. Steve SmithSeptember 15, 2015 at 2:46 PM

    No good data. Large QRST angle does not imply STEMI. greater than 100 I would always consider abnormal. What it indicates depends on many factors.

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  5. UnknownJune 24, 2016 at 3:49 AM

    I was waiting for this kind of lecture since long..THNX U sooo much...My question is in majority of females with or without chest pain we see so many repolarisation abnormalities so calles T wave changes..why so? It unnecessarily ends up investigating further including angio..as they complaints also some kind of non specific chest pain many times...Sir please opine..thanks once again

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  6. Steve SmithJuly 8, 2016 at 8:21 AM

    Only because the usual teaching is that T-wave inversion is ischemia and dangerous, when in fact most is benign. But it is not simple to tell the difference. Takes lots of study and experience.

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  7. nicolo` crosa di vergagniMarch 31, 2017 at 8:28 PM

    thank you doctor

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  8. MGJuly 10, 2017 at 5:20 AM

    hello
    8:53 28/F with anxiery and CP... any comments on lead 1 T wave in both ECGs??

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  9. MGJuly 10, 2017 at 5:58 AM

    40:08.... which wall is involved?????????

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  10. VittoxviiiSeptember 5, 2017 at 11:34 AM

    Hi Dr.med Smith,
    As I am about to complete my first year of residency (cardiology) I discussed T wave inversions and Wellens Syndrome with my fellow colleagues.
    One of my colleague is just doing a six month rotation in our Cardiology department and asked an intersting questions.
    With a patient with Wellens Syndrome, now pain free, after 6h from the first pain episode is it possibile that the high sensible troponins stay negative?
    In that case (negative high sensisble troponins) should the patients be still sent to the cath lab or sent home and undergo an elective II level imaging test (RM/ TC)?
    My opinion on the latter is that with a pathological ECG and no clear cause (unseen/unknown wellens ECG pattern) patient should stay hospitalized.
    I'm interested in what you think about these two questions.

    Thank you for your help and congratulations on your excellent blog.

    Dr.med Beltrani Vittorio
    Cardiocentro Ticino
    Swtizterland

    ReplyDelete
    Replies
    1. Steve SmithSeptember 12, 2017 at 3:07 PM

      Beltrani,
      There are many false positive Wellens' (search this blog for PseudoWellens). A lot depends on what you consider "negative" for hs cTnI. Below 99% only? 2 values that are below but have a delta? Or two values that are below the LoD? all very different. Also, what if the T-wave inversion resolves? Such dynamic T-wave inversion is NOT Wellens' but is unstable angina and will often have negative troponins. If it is Wellens', it must evolve (see this: http://hqmeded-ecg.blogspot.com/2011/03/classic-evolution-of-wellens-t-waves.html ). If no evolution, then not Wellens' and negative trops are true negative. I would say if both below LoD, then definitely not Wellens'. If both below 99% and no delta, then almost certainly not Wellens'. But if either is above 99%, or if both below 99% but with a significant delta, it certainly may be Wellens'.
      Steve Smith

      Delete
    2. VittoxviiiSeptember 14, 2017 at 2:51 PM

      Thank you for your precise and enlightening answer.
      Best Regards,
      Dr.med Beltrani

      Delete
  11. tom fieroOctober 20, 2017 at 8:55 PM

    thank you, Steve. at least now i am beginning to see how much more i need to learn. it is funny . in our ER we get handed EKG's to read (from all parts of the ER), regardless sometimes of what else we are doing (i might even be in the lavatory), to just quickly read and mark "no STEMI", based on the standard ST elevation criteria. but as you have shown repeatedly, it is so much more than just 2mm ST elevation in two contiguous leads, (or 1.5 for girls and 2.5 for boys...). and that is what makes it so terribly interesting, and challenging.
    tom
    thank you

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  12. MGNovember 28, 2017 at 2:24 AM

    Hello doctor.. Any links to your blog which talks more about QRS/T angle and its significance?
    Thanks

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    Replies
    1. Steve SmithNovember 28, 2017 at 6:52 AM

      Sorry, not much else.
      Try this: https://scholar.google.com/scholar?hl=en&as_sdt=0%2C24&q=QRST+angle+ekg&btnG=

      Delete
  13. muttiplayMarch 24, 2019 at 8:10 AM

    2:40 "If the voltages are that high we can't diagnose Wellens because it might be a false positive due to LVH" Is there a cutoff to define "high voltages"?

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    1. Steve SmithMarch 25, 2019 at 7:38 AM

      I wish I could tell you a number! no research on that.

      Delete
  14. AnonymousOctober 4, 2019 at 3:47 PM

    any pdf version of this wonderful lecture?

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    Replies
    1. Steve SmithOctober 9, 2019 at 4:32 PM

      I have not made one, but that's a good idea. I'll try to get around to it.

      Delete
  15. KambouroffOctober 15, 2019 at 10:55 AM

    Thank you Dr. Smith for all the great lectures, discussions and ECG cases.

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  16. Aykut ÖzkanFebruary 24, 2021 at 12:06 PM

    thank you very much for this amazing lecture, hope to see more like these..

    ReplyDelete
  17. Alberto RossettiMarch 7, 2021 at 6:08 AM

    Thanks for the lecture!
    It definetely shedded some light on my confusion about T wave patterns in ischemia. However I would love to hear an hypothesis regarding WHY does the T wave becomes negative only upon repersion. I am doing a Phd in cellare EP. Electrophysiologically, a discordant T wave means you have an inversion of the normal paatern whereby earlier activates area repolarize after (ie. they a longer action potential duration) the later activates areas (in textbooks, the epicardium). But why would ischemia not produce such a phenomenon during ongoing occlusion? Thanks in advance, I hope my question is clear

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  18. Alberto RossettiMarch 7, 2021 at 6:11 AM

    Thanks for your lecture! I am curious to learn what is in your opinion the mechanism whereby the T wave only become negative after reperfusion occurs.

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    Replies
    1. Steve SmithMarch 27, 2021 at 10:34 AM

      There are theories about that, but it is more important to just know that the phenomenon is real. Theories have to do with repolarization dispersal in the ischemic area around the infarct zone

      Delete

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