My Mom Has Been Told She Has An Enlarged Heart

My mom has been told she has an enlarged heart and she has gained 15 pounds (but it has to be fluid because she hasn't been eating). She had to go to her appointment alone because we live in different States. So as she was telling me her symptoms, I was wondering if there would be any possibility that it would have been a virus or something that she got from her cats. She most likely would not associate it with them, however, I was curious if it would have any affect on her treatment.