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These changes are often a normal variant / especially in certain race; or gender - eg. women.
However, it may also be due to reduced blood supply to the mid-portion of the heart.
Electrical interference, muscle movements can cause artefacts.
Repeat the ECG / Do blood tests (cardiac markers) and/or ECHOcardiogram
If all are well, one is re-assured. Any suspicion needs further investigation.
Wishing speedy recovery