ECG of the Week - 10th September 2012 - Interpretation

This ECG is from an 84 year old male, no other clinical information available.

Click to enlarge

Rate:

• ~ 48

Rhythm:

• Sinus
• Irregular

 Axis:

• Extreme / NW (-141 deg)

Intervals:

• PR - Prolonged (~240ms)
• QRS - Normal (80ms)
• QT - ~480ms (QTc Bazette ~ 400 ms - difficult due to variable rate & T flattening)

Additional:

• T Wave Flattening V5-6, I, II, III, aVF
• U Waves V2-6, ? I & II - Apparent T wave in Lead II likely U wave
• Dominant R wave aVR
• R wave progression V2 to V3 appears abnormal
• Movement Artefact between 3rd & 4th Complexes

Interpretation:

• 1st Degree AV Block
• Bradycardia
• U waves & T wave changes suggestive of hypokalaemia - unfortunately unable to correlate with clinical case
• Extreme Axis & Dominant R wave aVR consistent with Right Arm / Left Arm Lead Reversal - resultant Lead I inversion and Leads II / III switch places
• Unusual R wave progression V2 to V3 - ? lead placement, ? patient habitus, ? lead reversal (unlikely due to local cable set-up)

Another ECG was performed with the Right Arm and Left Arm lead positions corrected and is shown below. Note Left Axis Deviation with corrected lead placement

Click to enlarge

References / Further Reading

Life in the Fast Lane

• Hypokalaemia here
• 1st Degree AV Block here
• Lead Reversal Overview here

Textbook

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