Friday, 27 November 2015

ECG of the Week - 23rd November 2015 - Interpretation

This ECG is from a 75 yr old male who presented complaining of lethargy, nausea and shortness of breath. You have no old ECG's for comparison.

Click to enlarge
  • 66
  • Regular
  • No P waves present
    • Accelerated Idioventricular Rhythm (AIVR)
  • Normal
  • QRS - Prolonged (160ms)

  • Discordant ST segment changes
  • Excessive depression in lead V5 and excessive elevation V3 (just on -0.25 ST elevation / QRS depth)


  • LBBB Morphology
    • Deep S in V1-3
    • Broad R wave in lateral leads
  • T waves massively disproportionate and peaked
  • Note in leads V5-6 terminal portion of T wave becomes positive

The key abnormalities on this ECG are:

  • AIVR
  • LBBB with abnormal ST changes
  • Massive peaked T waves

Broad differentials would include

  • Ischaemia
  • Drug toxicity
  • Acid-base disturbance
  • Electrolyte abnormality

At first glance I'd favour hyperkalaemia as the culprit and an urgent VBG was taken - K 8.8 mmol/L !

I unfortunately don't have a follow-up ECG and I expect following treatment sinus rhythm was restored and the T wave changes normalised. I would be interested to know if the LBBB was longstanding or secondary to the hyperkalaemia,

References / Further Reading

Life in the Fast Lane

  • Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.