DH has been on a low/no salt diet for about 19 years. When he fell off the wagon a few years ago, he ended up in the hospital like you. It wasn't the hospital where his doctors all practice and we were at the mercy of a heart doctor who refused to let him go even after they got the fluid off of him. It was a royal mess, so we decided that was not going to happen again.
Cabelas makes a lot of really good salt free rubs and spices for meats and vegetables. Like others have said, use spices instead of salt. I do not cook with any salt at all.
Eating out is NEVER salt free. There is so much salt added to the food. Even salads. Most large chains have nutrition statements on their websites.
Also, read every label because some foods that normally don't have salt may be saturated with sodium salycitic acid which is a salt solution to aid in preservation.
Fresh food is always best, but read labels.
You must always monitor your fluid intake. DH weighs himself every morning. A couple pound weight gain overnight signals the need to cut way down on food and fluid for a day or two. When that happens he will eat a "lean cusine" dinner (never more than 500 milligrams of salt) for a day and that normally gets rid of the problem.
Dale