Wednesday, 19 December 2012

ECG of the Week - 17th December 2012 - Interpretation

This ECG is from 46 yr old man presenting with several months of exertional dysponea and fatigue. At the time of review his BP was 110/60 mmHg.
Thoughts ? Differential diagnosis ?

Click to enlarge
  • Atrial Rate 83 bpm
  • Ventricular rate 42 bpm
  • Regular
  • No relationship between P waves : QRS complexes
  • Normal (~65 deg)
  • PR - No relationship
  • QRS - Normal (80ms)
  • QT - 440ms (QTc Bazette ~ 390 ms)
  • Apparent ST elevation in V3 although likely to be secondary to p wave superimposition
  • Complete heart block with junctional escape rhythm.
Differential Diagnosis
  • Ischaemia
  • Medications
      • Cardiotoxic agents
        • Therapeutic
        • Delibrate Self Harm
  • Electrolye / Acid-base disturbance
  • Aortic Valve Disease
  • Congenital Cardiac Disease - Valvular or EP disturbance
  • Sarcoidosis
  • Myocarditis
  • Thyroid Dysfunction - Hyper- or hypo-
What happened to this patient ?
  • Stress Echo - Nil evidence ischaemia with normal LVEF
  • Cardiac MRI - Nil evidence sarcoidosis
  • PET Scan - Nil evidence sarcoidosis
  • Nil reversible / correctable cause found for CHB
  • Dual chamber PPM Implanted (MRI Compatible)
Thanks to both Christopher and Vince DiGuilio for their comments on this ECG.

Don't forget to check out Christopher's works over at and if his Blogger profile is right, over here as well Paramedicine101. 

Check out Vince's Google+ ECG+ Community for more excellent ECG discussions, and check out his website The Medical Appraoch to EM. You can also follow Vince on twitter @MedicalApproach

Thanks to Dr Shakeeb Razak for sharing this interesting case.

References / Further Reading

Life in the Fast Lane

  • Complete heart block here
  • Kandolin R, Lehtonen J, Kupari M. Cardiac sarcoidosis and giant cell myocarditis as causes of atrioventricular block in young and middle-aged adults. Circ Arrhythm Electrophysiol. 2011 Jun;4(3):303-9. PMID: 21427276 Full text here
  • Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.


  1. Adam Thompson runs Paramedicine 101, but I haven't posted anything since 2010.

    Thank you for the link!

  2. Thanks for the links as well!

    Awesome case, with a really interesting workup. We have to farm out most anything more than an echo at my place, so I don't get to hear much about folks getting PET scans to look for sarcoidosis and things like that.

    I had also never really considered thyroid dysfunction in my CHB differential. It's something I think of with tachy or bradycardia rhythms sometimes, but the CHB cases are new to me. Thanks for posting!