MI with No damage?

I'm working on cardiac care unit PRN now. I obviously need to further educate myself on MIs because I thought all MIs meant there was some kind of damage to the heart muscles. Can one have an MI eith absolutely no damage at all?

You're correct. "infarction" means myocardium has been lost...whether a large area or not. We know this because enzyme elevation (specifically troponin) is released as a result of myocardial cell death. (if there is no 'bump' in troponin/enzymes then the 'event' was likely angina, etc. rather than a true MI).

At any rate, a 'small' MI (ie many non Q-wave/non ST-elevation MI's...or an MI caught/corrected early enough....for example) are 'true' MI's but may causee no lasting 'damage' or 'effects' to the heart. The echo will be normal, etc....even in the face of a troponin bump.

So...yes your heart IS 'damaged' by any MI...but with some 'small' MI's, your cardiac function will remain absolutely normal.

thus... the answer to your question is "yes and no"

On Non-Q wave MIs, and NSTEMI MIs, (Non-STEMIs, or No ST Elevation MIs), the thought is that the infarction did not go all the way through the myocardial tissue, therefore the cardiac fuction is not, or very minimally impaired.