Gallbladder/Liver cleanse and heart problems?

Hi!

So, my grandpa is turning 77 this year and he has had two heart attacks in the past that made it so part of his heart just doesn't pump either any blood at all or hardly enough for him to be as strong as he was before. Recently, he found out he has a 2 cm gallstone lodged near the bottom of his gallbladder that's really causing him pain and it made his gallbladder infected. The doctors wanted to take it out, but because of his heart issues, they weren't sure he would wake up from the anesthesia and and instead voted to put a tube in through his liver into his gallbladder to drain the infection out. While that's great and all, the stone will still be there and if he doesn't get it out, it's going to kill him. For some reason, they think they can get his heart strong enough to do the operation, but he doesn't feel like that's going to be an option. Ultimately, my question is, does anyone know of any other options he has for a cleanse or things to stay away from that he can do even with his heart complications? I know about the amazing liver and gallbladder cleanse and I was looking into that, but he can't take the Epsom Salt because of his heart and he's on a low fat restriction so the olive oil is a no go. Any advice would be greatly appreciated!