Wednesday, 28 October 2015

ECG of the Week - 26th October 2015 - Interpretation

The following ECG is from a 65 yr old male who presented with shortness of breath worsening over several months.




Click to enlarge



Rate:
  • 72 bpm
Rhythm:
  • Regular
  • Sinus Rhythm
Axis:
  • Right axis deviation (~125 deg)
Intervals:
  • PR - Normal (~200ms)
  • QRS - Prolonged (140ms)
  • QT - 440ms (QTc Bazette 380-400 ms)
Segments:
  • ST Depression leads II, III, aVF, V1-4

Additional:
  • T wave inversion leads II, III, aVF, V1-5
  • Peaked P wave in lead II
  • RBBB Morphology
  • R/S ratio in lead I <0.5 
Interpretation:

In isolation there are several broad differentials for these ECG features including:

  • Acute RV strain e.g. PE
  • Chronic RV strain with resultant RV hypertrophy
  • Ischemia
  • Raised ICP
  • Myocarditis
  • Cardiomyopathy

This patient had already had extensive investigation by his primary care physician and his recent ECG's were identical to the one above. He had also had a recent echo.

What did the echo show ?
  • Concentric LVH
  • Normal LV size and systolic function
  • Severely dilated right ventricle
  • Moderation RV systolic impairment
  • Dilated right atrium
The patient was admitted under the General Physicians for medical management of his right heart failure which was secondary to chronic pulmonary disease.

Right Ventricular Hypertrophy (RVH) 

Check out the link to the Life in the Fast Lane ECG library page on RVH below to find a list of the ECG RVH criteria. The diagnosis of RVH with RBBB is a difficult one but our ECG above has many features which suggest RVH in the setting of RBBB:

  • Right axis deviation + RBBB
  • R/S Ratio in lead I <0.5

Other features that suggest RVH in RBBB are:

  • R' wave height >15mm
  • Right Atrial Enlargement - our ECG is suggestive but doesn't quite met the voltage criteria

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.