Wednesday, November 21, 2018

A Computer "Normal" ECG. What is the diagnosis?

I posted this one on October 9, but it was buried in a discussion of a paper on triage ECGs:

Another Inadequate Paper Published on Triage ECGs, whose Conclusions Need Scrutiny.

I wanted to put it out there on its own:

These are diagnostic hyperacute T-waves.
You can see the computer interpretation above.
This patient had an acute LAD occlusion and was sent to the cath lab immediately by an Emergency Physician trained at Hennepin who had no doubt about the diagnosis.

Comment by KEN GRAUER, MD (11/22/2018):
As noted by Dr. Smith — the ECG in the above Figure in a patient with new symptoms is diagnostic of acute LAD occlusion because of the presence of hyperacute ECG changes. Specifically, the abnormal ECG findings include:
  • T waves in leads V2-thru-V6 that are most definitely much-taller-and-fatter-than-they-should-be given the amplitude of the respective R wave in these same leads. These are hyperacute waves.
  • The onset of the disproportionately tall-and-fat T wave in lead V2 begins with slight J-point ST depression. Thus, the appearance of the ST-T wave in lead V2 is typical for DeWinter T waves — that of itself, when seen in anterior leads of a patient with new symptoms, indicates proximal LAD occlusion.
  • There is slight-but-real ST elevation in lateral chest leads V5 and V6.
  • In the setting of new-onset chest pain — the appearance of Lead aVL in this tracing is also by itself diagnostic of acute OMI. In addition to the QS complex in this lead — there is clear straightening of the ST segment takeoff that is elevated above the baseline.
  • The other high-lateral limb lead ( = lead I) — also manifests ST elevation, here with a disproportionately tall and fat T wave.
  • There are reciprocal inferior lead ST segment changes. While the amount of ST depression in these leads is minimal — the scooped ST segment appearance in each of the inferior leads is clearly not “normal”. In the context of the hyperacute changes seen elsewhere — the ST-T wave appearance in the inferior leads qualifies as a reciprocal” change.
PUTTING IALL TOGETHER — The presence of hyperacute ST-T waves in leads V2-thru-V6 (maximal in V2-V4) — in association with lateral lead ST elevation + diagnostic ST elevation in lead aVL + reciprocal inferior lead changes is diagnostic for acute proximal LAD occlusion.
  • P.S. — The computer completely missed the diagnosis of acute OMI in this case — as it interpreted this tracing as a “Normal ECG”. That said, this failure of the computerized report to recognize the obviously abnormal ECG findings in this case is NO excuse for clinicians not to pick up on the abnormal findings. Clinicians must always independently interpret each ECG they encounter.
  • Regarding the computer — I feel that there are potential benefits to computerized ECG interpretations. That said, to appreciate how to optimize use of the computerized report requires appreciation of what the computer is good at — and, what it is likely to miss. CLICK HERE — for more on "My Take” on this subject.

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