Weiner dog

My Weiner dog whom is 10 years old started having some swelling in her stomach and her her heart can be seen beating hard and she is breathing harder   I took her the vet they did chest x-ray  said she has congested heart failure  but I'm wondering if it's possible she could have eaten something and has a blockage somewhere in her stomach or intestines that has her heart goin haywire instead she has been like this for a week now and they have her on 2 diff heart pills and a water pill and it doesn't seem to be making any difference if u touch the side of her stomach she doesn't like it  they didn't do a X-ray on her stomach  is this a possibility ? She hasn't eaten in two days she is still drinking water but she has a bowel movement and it was black in color. Could she have something wrong in her stomach area making her heart go crazy ? It seems if she was in congested heart failure wouldn't her heart have given out by now? How long will they live like this?

Hello - congested heart failure can be visible on and diagnosable a radiograph and might explain changes to a dogs' breathing. However, it may not explain black faeces and a very painful abdomen so easily.  I wonder whether more than one thing might be going on in this patient at the same time? It sounds as though more investigation may be needed and as though triage for an emergency appointment may be needed.