Brief Answer:
No serious damage; no they are different

Detailed Answer:
Hello ma'am, welcome and a very good Sunday to you too.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. 'No irreversible structural damage to the myocardium' indicates the absence of any damage to the heart resulting from ischemia (lack of blood supply), which can result in death of cells, tissue and heart muscle. If at all there is ischemia it can result in death of cells and tissues in the heart, which can result in a heart attack (medically called myocardial infarction). But this cell/tissue death can be reversed if treated urgently.

I hope this makes the statement 'no irreversible damage to the heart' clear. If at all it is not clear, please write back to me and I shall try my best to explain things in a better manner.

A hibernating myocardium is not the same as a heart attack, but it does mimic a the presentation of a heart attack. So it is not a heart attack, but at times it can be caused due to ischemia (lack of blood supply), which as explained above can also lead to heart attacks.

I hope you find my response helpful ma'am. Please feel free to write back to me for any further clarifications, I would be more than happy to help you.

Best wishes.

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