I don't think it has to be replaced at any time because tissue grows to cover the hole once the implant is in place. This will grow with the heart.
I think Irineo is right,
Have a look at this:
I honestly don't know but when I went to a health fair a few years ago, they had a table of the "patches" used for closing holes. It was like a collapsed umbrella - they insert it via catheter, place it and then pop it open. My understanding is that the heart tissue adheres in time to the mesh structure so it doesn't shift. I'm not sure how they would remove that without tearing a larger hole in the heart structure. But I'm not a cardiac surgeon either.