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Now, in the depression tracing, there is a significant depression in the middle part of the strip for a few beats, but depression in the remaining part is physiological. Similarly, the elevation is significant in the earlier part of tracing while nonsignificant in the later part. Now, this is quite unusual to see that with continuing exercise, some beats show significant changes while rest are physiological. So, there is a possibility that this is artefactual due to unstandardized machines. Also, you do not have any symptoms like chest heaviness, pain or undue breathlessness, dizziness during exercises, supports this possibility. But it is worthwhile to evaluate you. It is unlikely for someone to have ST elevation without symptoms. But, I think routine TMT (treadmill test) should be obtained to clear the doubt. If you have any risk factors like smoking, family history, dyslipidemia, etc., then it better to have TMT.