Wednesday, 17 February 2016

ECG of the Week - 15th February 2016 - Interpretation

The following ECG is from an 86 yr old female who presented following an episode of chest pain. She has a dual chamber PPM in situ following a prior episode of complete heart block. Old ECG's revealed an A-paced rhythm with no lateral / high lateral T wave inversion.



Click to enlarge
Rate:
  • 60 bpm
Rhythm:
  • Regular
  • A-paced rhythm
    • Atrial pacing spike with subsequent atrial depolarisation p wave
    • QRS Complexes conducted in native pattern via AV node
Axis:
  • Normal
Intervals:
  • PR - Normal (~200ms)
  • QRS - Normal (100ms)
  • QT - 440ms (QTc Bazette 440 ms)
Segments:
  • ST Elevation <1mm lead aVR
  • ST Depression leads II, V4-6
 Additional:
  • Biphasic T wave lead V3
  • T wave inversion leads I, aVL, V4-6
  • Borderline LVH by voltage criteria

Interpretation:
  • ST Segment changes in lateral / high lateral leads
Differentials
  • ACS 
    • Most likely given history of chest pain and new changes when compared with old ECG's
  • T wave memory
    • Potential for ST / T wave changes to be due to a period of V-paced rhythm
    • We have covered T-wave memory before here and here
  • Secondary to LVH
  • Drug effects especially digoxin although not typical appearance
 What happened ?

The patient was admitted under the Rehab team and had a troponin raise, following discussion with cardiology the patient was deemed for medical management only.

References / Further Reading

Life in the Fast Lane

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