Pet owners Information
As heart disease gets worse in cats, this can lead to fluid building up in or around the lungs. This makes it difficult to breathe. This is an urgent (and potentially an emergency) condition and needs urgent treatment. The good news is, there is usually treatment that can make your cat feel better. This information guide will help you understand the condition and help you treat and monitor your cat.
What is Congestive Heart Failure?
Worsening heart disease in cats (usually due to abnormally thickened heart muscle) can result in fluid building up in or around the lungs - this is called Congestive Heart Failure, or CHF. I don’t like this term, as the word “Failure” sounds like nothing more can be done. Ultimately, it just means your cat’s heart is struggling to cope with the underlying muscle disease. Of course, as the amount of fluid gets worse, this can result in severe difficulty breathing, which can become life-threatening if not treated.
How do we look out for CHF?
As fluid in the lungs makes breathing more difficult, then your cat’s breathing will get faster and often deeper. As such, a great, cheap and accurate way of monitoring your cat is by checking their breathing rates. This is best done when they are sleeping (as breathing rates increase when they are awake, and even more so when they are excited/running around). Try and do this at the same time each day, when your cat has been asleep for 20 minutes or so.
Count how many times your cat’s chest rises in 30 seconds (note that your cat’s chest will move up once and down once in each breath) - double your number to get a breathing rate per minute. In most cats, a normal rate is less than 20 breaths per minute. We get concerned if the rate is consistently above 30 breaths per minute. Any cat will occasionally have a rate over 30 breaths per minute (eg if they are dreaming, or really hot). Cats with CHF tend to have a gradual increase in their breathing rates over a number of days, and this is sustained. If your cat’s breathing rate is consistently over 30 breaths per minute, or you just notice that your cat’s breathing is really deep and they aren’t moving around the house as much, then you should contact your vet ASAP. This may have to be an urgent or emergency appointment if you are concerned.
How do we know if my cat has fluid building up?
Sometimes we can get an idea by a thorough examination, but the way to tell if there is fluid buildup is to look for it - most commonly we would do this with an ultrasound (not requiring sedation) or with a chest X-ray (often requiring a light sedative). Sometimes we may trial treatment if we are highly suspicious of the presence of fluid.
How do we treat the fluid?
The fluid may sit either inside the lungs (much like water inside a wet sponge), or sit outside the lungs, causing the lungs to get squashed. With fluid inside the lungs, it cannot be physically removed using a needle. So we use medicines called diuretics (also known as “water tablets”). If there’s a buildup of fluid outside the lungs, stopping the lungs from filling up with air easily, then we often need to remove this with a needle. We will usually give your cat some sedation first so they don’t feel anything.
Once the fluid has been removed, then we use diuretic medicines to help keep it away. There are various different types of diuretic, most commonly either furosemide (aka frusemide, Libeo) or torasemide (aka torsemide, Upcard, Isemid). These will help get rid of the excess fluid; the body does this by weeing out the excess fluid. To compensate, your cat may drink more water (this is normal).
These medications will continue for life, although we may vary the dose depending on how your cat is doing. Higher doses are often required at the beginning to get rid of the fluid and then we may be able to lower the dose longer term. When we use higher doses of these diuretics, this causes lots of weeing. As your cat may not have as much energy to go outside as often and as far, then making sure there are plenty of litter trays in the house can really help make them feel more comfortable. Frequent check ups are required in order to make sure the medications and the doses are correct. Sleeping breathing rates will usually reduce back down less than 30 breaths per minute once the
excess fluid is under control. Continue to count breathing rates every day forever as this will help us adjust the diuretic doses. As always, let your vet know if the breathing rates go back up to regularly over 30 breaths per minute.
You should make an appointment earlier if you notice your cat not doing as well (e.g., worse breathing, lethargic, not eating etc).
What happens then?
Our aim is to make sure your cat is happy and well. Every cat is going to need lifelong treatment of some sort, so don’t stop giving the tablets unless you are specifically told to.
Cats are not always the easiest to get medicines in to, so if you miss a dose, don’t worry and give it when it’s next due. If it’s regularly a problem, then get in touch with your vet, as there’s often alternatives (eg liquids, different tablets etc). We fully expect ups and downs, so if your cat isn’t doing well, then make an appointment so we can see what is going on and how we can help; there is often lots we can do.
Of course, over time, the heart continues to get worse and at some stage the amount of fluid in/around the lungs will continue to get worse despite the treatment. If we cannot make your cat feel better, then this is when we would discuss what your cat’s quality of life is like and whether we should discuss euthanasia before they start to suffer. For more challenging cases, or if you want more advice, your vet may recommend an appointment with a Cardiologist (either in your practice, or by visiting a Specialist hospital).