Hi all.My dad is still doing fine,but his feet have been swelling a little more than before.The left is bigger than the right.Does that have anything to do with the heart?

The hospice nurse said it's very common with the heat.
Is this true? Or is this like everyone says-the fluid starting to build up?
He did wheeze a little a few days ago so I gave him albuterol.He hasn't wheezed since.

The nurse said to let him know if dad starts wheezing.I asked the nurse what does wheezing have to do with it.
And he said usually the fluid goes down,but can sometimes back up into the lungs.

Can someone please explain this to me.My dad is urinating,so where is the fluid coming from?
Thanks.