Wednesday, 29 July 2015

ECG of the Week - 27th July 2015 - Interpretation

This ECG is from a 28 year old female who presented complaining of intermittent pre-syncope and palpitations. She is normally fit & well and is 34 weeks pregnant.
Check out the comments from our original post here.



Click to enlarge
Rate:
  • 78
Rhythm:
  • Regular
Axis:
  • Normal
Intervals:
  • PR - Short (~200ms)
  • QRS - Normal (80ms)
  • QT - 320ms (QTc Bazette 365ms)
Segments:
  • Subtle ST depression leads I, V4-6
 Additional:
  • Voltage criteria LVH
    • S wave V1 + R wave V6 =~38mm

Interpretation:
  • Short pr
    • Could this be Lown-Ganong-Levine ?
  • Voltage criteria for LVH

What happened ?

The patient was admitted for investigation under joint care of cardiologists and obstetricians.
Investigation for PE was normal. Echo showed:
  • Normal left ventricular size with normal wall thickness and normal systolic function.
  • Possible mild dilatation of the right ventricle
    • May be physiological due to stage of pregnancy.
  • Normal right ventricular systolic function.
  • Normal atrial size
  • No significant valvular abnormality
In-patient telemetry revealed no arrhythmia despite the patient complaining of palpitations.
The patient was discharge with on-going obstetric follow-up.

Lown-Ganong-Levine (LGL)

LGL is often grouped with WPW as part of the pre-excitation syndromes the major ECG difference is that LGL has only pr shortening without the QRS changes associated with WPW. The advent of EP studies has resulted in a greater understanding of cardiac conduction and it's role in arrhythmogenesis with the existence of LGL as a clinical entity disputed. It is likely the short pr reflects an extreme of the normal variation and may not play any role in arrhythmogenesis.
This eMedicine article has a great review of LGL an the current evidence around it's existence as a clinical entity:
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.