Bless your heart. I'm so sorry for all your problems! Believe me, I know all about the pain. I've been a chronic painer for over 25 years, and there are times I want to tear my hair out.
When I had my first spinal surgery, my surgeon sent me to "back school" -- it was at a rehab place where they taught us the correct mechanics for the back, plus other tricks. One main thing they taught was to NEVER use HEAT on the spine when it hurt -- heat draws blood to the heated area which causes more swelling & pain. You need to use ICE, which will reduce the swelling, thus reduce the inflammation and pain. Sure, when you first put the ice on it hurts for a couple of seconds, but after that it feels GOOD. Wrap the ice in a towel -- never put the ice directly on the skin as it will damage the skin. Use the ice for 20 minutes every 2 hours. You'll find that your pain WILL be reduced!
I thought he was nuts, and I tried heat one evening and I ended up in SO MUCH PAIN that I could barely walk! So i immediately got the ice out and applied that and it was much better afterwards! I never did that again!
Have you tried the Lidoderm patches? Those are TOPICAL patches -- they don't get into the blood stream, but they CAN help some people. You might ask your doctor about them -- it's worth a try.
Have you ever tried a Tens Unit or would that interfere with your heart? The Tens Unit delivers electrical stimulation to the painful area, but ONLY the painful area. Ask him about that too.
Make sure when you lay down that you have pillows under your knees so that they're elevated. Laying flat puts too much pressure on the spine. Also if you're laying on your side, put pillows between your knees to keep the spine aligned. NEVER lay on the stomach! The spine does not like that!
You probably know all these things, but thought I'd mention them anyway. I hope you find something that eases your pain. It's just awful being in pain 24/7! My prayers are with you. God bless. Hugs, Lee