Hospitalization would seem to be the best way of treating this. However, you can also try a sodium free diet (read labels), have him abstain from cured meats like pepperoni, jerky, and bacon. Have him elevate his legs above his head as much as possible. Try TED (thromboembolitic deterrent) hose. They are compression stockings. They can be bought in most any drugstore, but if his doctor prescribes them, then insurance will cover the cost. Try this massage technique: Starting above the toes and using a lot of lotion, push down and then up with your thumbs. Continue this through the ankles and calves. Remember to keep putting on lotion. This massage will push the fluid up out of his feet and calves and give him some relief. If this can be done and then put on TEDS, it should give him a lot of relief. There are also abdominal wraps that are used for hernias or after C-sections. This would also give him some relief.
Regarding the cramps, have his doctor prescribe quinine. Also, his Lasix and Aldactone probably need to be increased to try to get the edema under control.
Hugs,
Connie
P.S. I was writing this when you posted, so it's good to know you are providing him with a healthful, salt-free diet. Because we get a lot of lurkers looking for info, I will let my post stand as is.