Young adult patient with pleuritic chest pain. Describe the ECG.
Describe and interpret this ECG
ECG ANSWER and INTERPRETATION
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
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.