Fluid around the heart - help please!

Our cat, Fluff, was not eating, could not walk more than 3 steps without laying down, and had a very difficult time breathing this morning. My husband rushed her to the vet and they did an xray and she has a large amount of fluid around her heart. We had been told that she had a level 3 heart murmur but it had not been a problem to this point. We brought her in last Friday because she had been sneezing a lot, but the vet thought it was allergies. He did encourage us to get an xray though, as they always have, to get a look at the heart area. Fast forward to today and this. She has never had these problems in the past. She looked horrible. The vet has her now and gave her an injection of diuretics and will call us to let us know how she responds.

She is only 3 or 4, we got her from the animal shelter when she was under a year. She seems to be a Maine Coon, but of course she is most likely just a mix that looks like a Maine Coon.

Can anyone give me any stories about their cats and something like this? We travel often to our inlaws and other places and don't know if we'll be able to leave her in anyone's care in case this happens again. We're not even sure she'll make it through today. I'm just not sure what to think or do.

Any words of wisdom are very appreciated!!!

Here is a picture of her laying in the window in the sun


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Never mind, we had to put her down this afternoon. She was not improving and only getting worse, despite diuretics and oxygen therapy.

OMG, I am so very sorry, just heartsick for you . She was a beautiful girl and so young. Oh hun, I too lost a cat last summer suddenly to heart failure and he was only four years too. I know how difficult this must have been for you this afternoon. Fluff knew how much you loved her and I am thankful you were there to give her a dignified passing. How just terribly painful. Many vibes your way tonight.

I'm so sorry you lost your kitty. Rest peacefully, sweet Fluff. Your meowmy loved you very, very much.

I am so very sorry - but try to take comfort that she was so very much loved during her too short time here.

I too am sorry you had to put her down, but know that you released her from some incredible pain that was waiting for her a bit down the road. She is beautiful and I hope one day soon, you will again open your heart and home to rescue yet another kitty.