My mom and dad had a Maine Coon previously. They also have a maine coon now that is a kitten.

We were told that the breed is susceptible to heart problems. You mentioned fluid around the heart.

Have they checked the heart for more problems??

Tiny, my dad's original Maine Coon, passed away from congestive heart failure. I know that isn't good news, but he was on the same heart medication that my father was (my dad has heart problems as well).

Can you find out whether it is a heart condition, and whether medication for congestive heart failure, or whatever the issue may be, could help???

I'm not saying that that's what your Maine Coon has, but I wanted to make you aware of what we found about the heart condition problems that is common for that breed.