Well, when you see pitting edema, the first things you think of are indeed heart, kidney, and liver problems. Apropos of the last two, has your lab
work ever turned up 'hypoalbuminemia'? Has anyone ever mentioned 'nephrotic syndrome' to you?
Your ticker has been checked out thoroughly, right? If it has been found to be in good shape, the chances are that it IS in good shape, because there's nothing subtle about right heart failure.
I gather you don't have congestive heart failure, either.