Saturday, 3 January 2015

ECG of the Week - 29th December 2014 - Interpretation

This week's ECG's are not examples of subtly but do highlight the need to repeat ECG's when things change. These ECG's are form a 40 yr old male who presented with a history of chest pain. 
Check out the comments on our original post here.

He was pain-free on arrival to the Emergency Department, his initial pain-free ECG is below (ECG 1) He then complained of chest pain and a repeat ECG was performed, image below (ECG ) the time difference between these ECG's is 4 minutes !.


ECG 1
Pain-free
Click to enlarge



Rate:
  • 72 bpm
Rhythm:
  • Regular
  • Sinus rhythm
Axis:
  • Normal
Intervals:
  • PR - Normal (160ms)
  • QRS - Normal (100ms)
  • QT - 400ms (QTc Bazette 440 ms)
Segments:

  • ST elevation lead V1 (<1mm)

Additional:

  • Biphasic T wave lead V2
  • T wave inversion leads I, aVL, aVR, V1, V3-6
    • Deep inversion leads V3-5 
  • Voltage criteria for LVH

Interpretation:

The differentials of deep T wave inversion are relatively broad but in a patient with a history of chest pain, a pain free ECG and these ECG features the major concern is Wellen's syndrome - signifying a critical LAD lesion. The patient's next ECG, taken whilst having chest pain, highlights the need to recognize the Wellen's pattern.

ECG 2
Chest pain
Click to enlarge
Rate:
  • 84 bpm
Rhythm:
  • Regular
  • Sinus rhythm
Axis:
  • Normal
Intervals:
  • PR - Normal (160ms)
  • QRS - Normal (100ms)
  • QT - 360ms (QTc Bazette 430 ms)
Segments:

  • ST Elevation leads I (<1mm), aVL (1 mm), V1 (1mm), V2 (6mm), V3 (7mm), V4 (7mm), V5 (4mm), V6 (1-2mm)
  • ST Depression leads III, aVF

Additional:

  • Note resolution of deep T wave inversion with hyperacute T waves on ST segments in leads V2-3
  • Voltage changes as above
Interpretation:

  • Antero-lateral STEMI
    • Occlusion of critical lesion suspected from first ECG

I don't have the follow-up angiogram report but I think this case nicely illustrates the need to recognize the Wellen's pattern. Check out the great overview of Wellen's with more ECG examples at Life in the Fast Lane ECG Library, link below.

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.