Wednesday, 21 May 2014

ECG of the Week - 19th May 2014 - Interpretation

This ECG is from a 40 yr old female with sepsis. The patient was intubated and requiring vasopressor support. Prior to this illness the patient was fit and well.
Thanks to Dr Nat for sharing this ECG.
Check out the comments on our original post here.



Click to enlarge
Click to enlarge

Rate:
  • 90 bpm
Rhythm:
  • Regular atrial and ventricular activity
  • Complexes #1-10 independent atrial and ventricular pacemakers
    • Variable relationship between p wave and QRS complexes
  • Complexes #11-15 sinus
    • Fixed pr interval with subtle change in associated qrs morphology - appreciated in lead II rhythm strip
Axis:
  • Normal
Intervals:
  • PR - Variable relationship in complexes #1-10 between p waves and QRS complexes. Complexes #11-15 fixed pr relationship with normal pr interval (ms)
  • QRS - Complexes #1-10 have broader width than complexes #11-15
Segments:
  • Minor ST depression V2
Additional:
  • T wave inversion lead III

Interpretation:
  • Isorhythmic dissociation
    • Independent activation of atrial and ventricles - complexes #1-10
    • Atrial and ventricular rates similar, ~90bpm
    • Restoration of sinus rhythm at end of ECG - complexes #11-15
    • Reflects SA node and junctional pacemakers with near identical rates
    • Requires no intervention
What happened ?

The patient made an uneventful recovery from their sepsis. 
Nil evidence of myocardial ischaemia with normal ECHO.

Some VAQ question thoughts

In this week's VAQ we had a patient deteriorate rapidly whilst ventilated. 
Check out two great case based discussions from Chris Nickson of Life in the Fast Lane for some pointers on how to approach this situation.



References / Further Reading


Amal Mattu ECG Videos
Life in the Fast Lane
Article
Textbook
  • Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.