Wednesday, 1 March 2017

ECG of the Week - 27th February 2017 - Interpretation

The following ECG is from a 55yr old male who is having episodes of chest pain with increasing frequency. 


Click to enlarge


Rate:

  • 108 bpm
Rhythm:
  • Regular
  • Sinus rhythm
Axis:
  • Normal
Intervals:
  • PR - Normal (160-180ms)
  • QRS - Normal
  • QT - 300ms
Segments:
  • Up-sloping ST segment in lateral precordial leads
Additional:
  • Prominent T waves leads II, aVF, V6
    • In relation to QRS magnitude
  • Low QRS voltage
    • No electrical alternans
  • Baseline artifact affecting leads V4-6 and end of rhythm strip
Interpretation:
  • Prominent T waves in the setting of chest pain are concerning for ACS
  • Requires serial ECG's looking for progressive ST segment change
  • Combination of low voltage & tachycardia should prompt consideration of pericardial effusion as a cause for the chest pain.
  • As with all ECG's the ECG features need to be considered in the patient's specific clinical context
What happened ?

The patient was admitted for investigation under the cardiology team. Serial troponins and D-dimer were negative and an angiogram showed only minor vessel irregularities. 

Causes of Low Voltage ECG

Whilst pericardial effusion / tamponade is the most serious cause of ECG low voltage it is not the only cause or the most common. Causes include:

  • Pericardial effusion
  • Tamponade
  • Pleural effusion
  • Obesity
  • COPD
  • Pneumothorax
  • Cardiac infiltrative disease
  • Hypothyroidism
  • Prior MI
  • Dilated cardiomyopathy
  • Incorrectly set ECG gain

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.