My mother had a heart attack a few months ago. The doctors inserted a non-coated stent into her heart and she was doing fine. A week ago she was having some shoulder pain, so she went to get it checked out. They cleared her but the pain did not go away. Yesterday she went in to get another test done and the stent had actually clogged again. Since it was only a few months old (and her heart conditions are genetic, not lifestyle related) they had ruled that the stent was clogged because her body was attacking the foreign object (the stent) in her body. They replaced the stent with a "coated" stent. I am concerned that this stent will be clogged as well. What are the chances this will happen?