Wednesday, 3 May 2017

ECG of the Week - 1st May 2017 - Interpretation

The following ECG is from a 27yr old female who presented with a 1 hour history of palpitations. She has a 12 yr history of intermittent palpitations which have not been captured during investigation.


Click to enlarge
 
Rate:
  • 162 bpm
Rhythm:
  • Regular
Axis:
  • Normal
Intervals:
  • QRS - Narrow
Segments:
  • ST Depression leads II, III, aVF, V4-6
  • ST Elevation lead aVR
Additional:

  • Variable notching before QRS complexes
    • Best seen leads V3-5


Interpretation:


  • Regular narrow complex non-sinus tachycardia
DDx include:
  • Atrial tachycardia with 2:1 block
  • Atrial flutter with 2:1 block - not typical baseline appearance
  • AVNRT
  • AVRT

What happened ?

Following vagal manoeuvres the patient reverted to sinus rhythm, ECG below:
Post cardioversion
The post reversion ECG does not show features of pre-excitation with a normal pr interval and normal QRS morphology, same as ECG during tachydysrhythmia. Note the ST segment changes have also resolved and likely reflect demand changes due to high heart rate rather than primary ischaemic pathology.


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.