I hope you recieved the other info but in answer to your question, yes the pain he feels has never been relieved since the heart attack. The stenting curbed the pressure but never cured the chest pain. It has never gone and it flucuates as I said on a pain scale of 4-8.
Has your Son had the pains ever since the Stent? or have they re-appeared since then?
It could be restenosis, a blockage forming in the stent. It could be another blockage is forming. There could be many reasons, but I would certainly get him to make an appointment with his cardiologist because there are tests which can be run to establish what the problem is.