ECG of the Week - 24th March 2014 - Interpretation

Another old case from my collection. I don't have any clinical information on the patient or clinical presentation.
Check out the comments on our original post here.

Click to enlarge

Rate:

• 36

Rhythm:

• Complexes 1-5
• Regular
• R-R Interval ~1500ms 
• Followed by pause
• Complex 6
• Occurs ~2600ms following complex 5
• Less than 2x preceding R-R interval
• No p waves visible

Axis:

• RAD

Intervals:

• PR - Nil visible p waves
• QRS - Prolonged (120-140ms)
• QT - 400ms

Segments:

• ST Elevation leads II, III, aVF
• ST Depression leads aVL, V1-5

Additional:

• T inversion leads II, III, aVF
• Artifact along baseline
• Wandering of baseline prior to 3rd complex and after 6th complex
• ? Pacing spike following 2nd complex likely artifact as nil further evidence of PPM activity

Interpretation:

Differentials for these ECG features may pending on the clinical scenario and patient factors but broadly include:

• Acute inferior +/- posterior MI
• Hyperkalaemia - broad, irregular complexes
• Drug toxicity - sodium channel blockade, digoxin
• Environmental - hypothermia
• CNS lesion - bleed, SOL, raised ICP

References / Further Reading

Life in the Fast Lane

• Inferior STEMI here
• Hyperkalaemia here

Textbook

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