Question 30.2

A 76-year-old male presented to Emergency Department with chest pain.

 from LITFL

a)    Describe the ECG shown on page 13 (ECG 30.2).    (15% marks)

b)    Describe the anatomical lesion/s resulting in these ECG changes and the mechanism of the changes in the aVR lead.    (25% marks)
 

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College answer

Not available.

Discussion

The already challenging process of finding ECGs which the college remove from their published papers (so they can reuse them) has been rendered even more challenging in the Cursed Second Paper of 2020 which was returned to the candidates without any official answers. So: this SAQ sounds like it might have involved ST changes in aVR, detailed by Robert Buttner and Ed Burns from LITFL. The image itself orginates from johnsonfrancis.org.

So:

a) The ECG changes in this tracing:

  • ST elevation in aVR
  • ST depression in other leads, most prominent in I, II and V4-V6

b) The anatomical lesion is proximal LAD occlusion, resulting in basal ischaemia.

The mechanism, to quote directly from Johnson Francis:

"ST segment elevation in aVR in proximal left LAD occlusion before first septal is thought to be due to transmural ischemia of the basal part of the septum. Injury current of basal part of septum is directed towards right shoulder and aVR."

References