ECG Case 032

Main Abnormalities

This ECG demonstrates many of the classic features of acute pericarditis:

• Widespread concave ST elevation with PR depression — most notable in I, II, III, aVF, V5-6
• PR elevation in the inverted leads aVR and V1
• Downward sloping of the TP segment = “Spodick’s sign”
• No reciprocal changes of STEMI
• ST segment / T wave ratio > 0.25 (favours pericarditis over BER)

ST elevation and PR depression

Spodick sign

Pericarditis versus Benign Early Repolarisation

Pericarditis can be difficult to differentiate from BER as both conditions are associated with concave STE. One useful trick to distinguish between these two entities is to look at the ST segment / T wave ratio:

• The amplitude of the STE (from PR segment to J point) is measured in V6 and compared to the T wave amplitude.
• A ratio of > 0.25 suggests pericarditis
• A ratio of < 0.25 suggests BER

Example 1: Benign Early Repolarisation

• ST segment height = 1 mm
• T wave height = 6 mm
• ST / T wave ratio = 0.16
• The ST / T wave ratio < 0.25 is consistent with BER

Example 2: Pericarditis

• ST segment height = 2 mm
• T wave height = 4 mm
• ST / T wave ratio = 0.5
• The ST / T wave ratio > 0.25 is consistent with pericarditis.

Further Reading

• Wiesbauer F, Kühn P. ECG Mastery: Yellow Belt online course. Understand ECG basics. Medmastery
• Wiesbauer F, Kühn P. ECG Mastery: Blue Belt online course: Become an ECG expert. Medmastery
• Kühn P, Houghton A. ECG Mastery: Black Belt Workshop. Advanced ECG interpretation. Medmastery
• Rawshani A. Clinical ECG Interpretation ECG Waves
• Smith SW. Dr Smith’s ECG blog.
• Wiesbauer F. Little Black Book of ECG Secrets. Medmastery PDF