Wednesday, 10 June 2015

ECG of the Week - 8th June 2015 - Interpretation

Two ECG's for this week's case. They are from a 59 yr old female with a history of IHD, prior stents to LAD and non-compliance with anti-platelet therapy. She presented following a bee sting with dysponea, urticaria and a brief episode of chest pain. The ECG's below were performed 20 minutes apart.
Check out the comments on our original post here.



ECG 1 At presentation
Click to enlarge

ECG 2 20 Minutes following 1st ECG
Click to enlarge
Features similar on both ECG's

Rate:
  • ECG 1 42 bpm
  • ECG 2 60 bpm
Rhythm:
  • Sinus Rhythm
  • Sinus Arrhythmia
Axis:
  • Normal
Intervals:
  • PR - Normal (~180ms)
  • QRS - Normal (100ms)
Key differences between ECG's

Segments:

  • ECG 1 Flat ST segment elevation leads V2 & V3
  • ECG 1 ST Depression leads II, III
  • ECG 2 Flattening of J point in leads V2 & V3
  • ECG 2 Positive T wave in lead V1 with ST elevation in V1


Interpretation:

  • Dynamic ST segment changes
  • DDx:
    • ACS in the setting of physiological stress
    • Kounis Syndrome

What is Kounis Syndrome ?

First described in 1991 by Dr N Kounis, Kounis syndrome is characterized by a group of symptoms that manifest as unstable vasospastic or non-vasospastic angina secondary to a hypersensitivity reaction and was initially termed 'allergic angina'.

There are three types of Kounis syndrome:

  • Type I: Chest pain secondary to coronary artery vasospasm in patients with no previous history of coronary artery disease
  • Type II: Patients with culprit but quiescent pre-existing atheromatous disease in whom the acute release of inflammatory mediators can induce either coronary artery spasm with normal cardiac enzymes and troponins or plaque erosion or rupture manifesting as acute myocardial infarction
  • Type III: Patients with coronary thrombosis (including stent thrombosis) in whom aspirated thrombus demonstrate the presence of eosinophils and mast cells respectively 

Further reading on Kounis Syndrome here:


Thanks to Dr Prathibha Shenoy who educated me about Kounis Syndrome, you can check out Dr Shenoy's Imaging Case of the Week at our sister site Emergucate here.

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