Please don't take this the wrong way but I think you shouldn't do this. You already have health problems and doing these kinds of tests on yourself could just end up making it worse. Why don't you just try to channel all that effort you would put on trying to live on water and just lift weights and absolutely destroy them each time you workout, while eating healthy and sleeping alot. That would be alot better for you. Only do this if you're doctor says it OK though and it won't affect your heart.