Hi there,
I am sorry your kitty is so ill. In addition to the radiographs, it would be a good idea to see if you can have a cardiac ultrasound done. If your vet has an ultrasound machine in the office, they may be able to do it for you, or call in a radiologist. Or, your vet can refer you to a specialist in your area where an ultrasound can be performed. Ultrasound gives more detailed information than radiographs, as it provides a 3-dimensional view of your cats heart and surrounding structures where radiographs only provide a 2-dimensional view. An ultrasonographer may be able to determine if it is actually a tumor attached to the heart. Often times heartworms can be seen on ultrasound inside the heart. If your vet hasn't done so already, it would also be a very good idea to run a feline heartworm test, which may have to be submitted to an outside lab. And, ofcourse, full bloodwork including a thyroid panel as well as a urinalysis should also be run to evaluate organ function and hydration status and screen for additional diseases that may be present. Undiagnosed and untreated illnesses will make it impossible to manage the breathing troubles your cat is experiencing. I would NOT consider surgery until all diagnostics have been run.
Due to your cats age and current condition, surgery to remove the mass is not really a good choice, and many vets will not even attempt this type of procedure (and they shouldn't). To address a heart-based tumor, the chest has to be opened, and that is a very serious and painful and difficult operation to recover from. If your cats lungs are filling with fluid, she may require a chest tube or multiple chest taps to remove excess fluid. Some animals are not a good candidate for these procedures because of the location of the fluid (sometimes it cannot be removed) and that is one reason why the furosemide is given.
You have to realize that even if you opted for surgery (provided you could find a vet that thought it was a viable option) your kitty may not have an extended period of time left. Cats are considered to be geriatric as early as 8 years old, and at 14 your kitty is elderly. She is suffering from advanced disease process and is in respiratory distress. The last thing you want to do is put her through a painful procedure with a protracted recovery time only to have her spend her last days suffering. This is where a good realationship with your vet is going to come in handy. I cannot see your kitty and do not have all the facts of her illness so it is harder to guide you. Surgery may be a viable option, but there are many factors that would make me steer away from that path.
The main goal here is the comfort of your kitty in her remaining days, and I am sorry to say that they may not be as many as you are hoping. I am not trying to be cruel, I just want you to have a realistic idea of the gravity of your kitties condition. You may have some tough decisions coming, and I am very sorry. You obviously love this kitty very much, and it is hard when your baby is sick. Please let me know if I can be of further assistance. If this has been helpful, please hit the green accept button.
Emergency Critical Care Nurse
16+ years of veterinary experience