Wednesday, 21 November 2012

ECG of the Week - 19th November 2012 - Interpretation


This ECG is from a 49 year old with chest pain.

 
 
Click to enlarge
 
 
Initial 3 Complexes

Rate:
  • ~65-68
Rhythm:
  • Regular
Axis:
  • Normal
Intervals:
  • PR - Normal (~160ms)
  • QRS - Normal (100ms)
  • QT - 400ms (QTc Bazette ~420-430 ms)
Segments:
  • ST Depression I, II, III
Additional:
  • P Wave Inversion Lead I
Interpretation:
  • Ectopic Atrial Rythm with ischaemic features
Subsequent ECG
  • Ventricular Ectopic with 'R-onT' phenomenon
  • Polymorphic VT --> VF
Interpretation:
  • Acute myocardial ischaemia / infarction causing polymorphic VT / VF
 What happened next ?
  • CPR
  • Received 4 x 200J shocks
  • 150mg iv amiodarone
  • 100 mg iv lignocaine

Subsequent ROSC was achieved after < 10 minutes. 
Post ROSC ECG showed antero-lateral ST elevation.
The patient underwent inter-hospital transfer for PCI.
PCI revealed a proximal LAD lesion with 90% occlusion, which was stented.
Echo showed
  • Normal LV size with anterior, septal and apical akinesis and overall moderate systolic impairment
  • Probable LV apical thrombus
  • Normal right ventricular size and apical akinesis and overall mild systolic impairment.
The patient was subsequently discharged on warfarin, anti-platelet therapy, ACE inhibitor, beta-blocker, and a statin.

Things to think about

  • The role of early revascularisation with thrombolysis prior to inter-hospital transfer
  • The role of lignocaine in shock refractory VT/VF
    • Several International Guidelines on ALS are linked to below and the recommendations on the use of lignocaine vary between guidelines

References / Further Reading
 
International Resuscitation Guidelines
  • Australian Resuscitation Council Guidelines here
  • UK Resuscitation Council Guidelines here
  • American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science 2010 Edition here
Textbook
  • Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.