In Case 105, a 70yr old male presented with chest pain, palpitations and hypotension. He underwent DC cardioversion and this is his post cardioversion ECG.
Describe and interpret this ECG
ECG ANSWER and INTERPRETATION
- Sinus rhythm
- PR – Normal (~180ms)
- QRS – Normal (100ms)
- QT – 320ms (QTc Bazett 370 ms)
- ST Elevation leads V1 & V3 ?? aVF
- ST Depression leads II, III, aVF, V5-6
- ST segment analysis difficult due to baseline wander
- Deep symmetrical T wave inversion leads II, III, aVF, V5-6
Without more clinical information on the case including prior medical history, findings on serial ECG’s, old ECG’s, and result of further investigations post this episode e.g. echo or angio it’s difficult to give a clear conclusion to this case and ECG.
The broad differentials for the findings on this ECG are:
- Structural Heart Disease
- Cardiac T-wave Memory
T wave memory is an interesting phenomenon that could explain the marked T wave changes seen on this ECG. It results in transient T wave changes following a period of abnormal ventricular conduction e.g. ventricular tachycardia, paced rhythms, intermittent bundle branch block or aberrant conduction.
Vakil et al provide a nice overview of T-wave memory, proposed mechanisms, and a case example.
The deep T wave inversion on this ECG correspond to the leads in which a negative QRS was seen in the patients pre-cardioversion ECG (Case 105) a finding consistent with T-wave memory. Patient’s often require work-up to exclude underlying ischaemia or structural disease but cardiac T-wave memory is a benign and self-resolving condition in itself.
- Vakil K, Gandhi S, Abidi KS, et al. Deep T-Wave Inversions: Cardiac Ischemia or Memory? JCvD 2014;2(2):116-118