Backing up Ed, never give up. Over the time span of 15 years I had a total of now eleven stents, I think Ed has about the same number. My health started to decline, I was no longer able to work out, walk hills, etc., and accepted the challenge of high risk by pass surgery.. High risk indeed, it failed for a number of reasons... not everyone's veins can be used as arteries, etc. A young Intervention doc came into the clinic I go to, we talked, and he said there was a high risk procedure to open my native arteries. I went with his advice and I'm still standing. The Left artery couldn't be opened, but the Right artery was opened. I'm still considered in the stage 4 heart failure level, but I'm better because of the new idea.
I'd look, like Ed says, a Cardiologist who has a way to help.
I know this sounds a bit odd, but there is nothing you can do, apart from live in hospital of course which means no life. Only when something goes wrong with your heart will you know, BUT you can promote shortcuts in the hospital. You can tell them you have heart issues, getting them immediately onto the right track. With regards to your right artery, you can of course try other facilities. I had a completely calcified left artery which 9 cardiologist told me was 'impossible to get through'. I then wrote to a training/research hospital in london where a cardiologist became intrigued with my case and agreed to see me. He said "I have many tricks up my sleeve to remove plaque, I can do it this afternoon if you like". There is always someone out there who can do these procedures and has lots of advanced techniques through a lot of experience, it's just finding them. However, the blockage is 80% and we don't know how long ago this began. It could have begun last year or 30 years ago, nobody can tell. Just because it is heavily calcified does't give a clue to its age.