Hello, pet parents! I don't want to scare you today, but if you're the proud parent of a furry feline, there's something you should know. This condition can turn your pet from a purrer to a painful howler, and worse than that, it can be life-threatening in no time at all. Here's what you need to know about saddle thrombus in cats, including how to spot the earliest signs.

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  1. What is a Saddle Thrombus
  2. Causes of Saddle Thrombus in Cats
  3. Signs of Saddle Thrombus in Cats
  4. Treatment for Saddle Thrombus in Cats
  5. How Can the Emergency Fund Help with Treatment
  6. FAQs
  7. Conclusion

What is a Saddle Thrombus

Saddle thrombus might have a somewhat fun-sounding name, but it is not a fun condition. The scientific name for the condition is Feline Aortic Thromboembolism, sometimes shortened to FATE, and it is a medical emergency that requires URGENT medical intervention.

Let's break the name down.

'Thrombus' is, to put it bluntly, blood clots. Thrombi means one clot, singular. The term 'saddle' refers to the way the blood clot sits after it escapes the heart and then travels around the body, eventually resting on the top of the rear leg vessels. The clot sits just like a saddle, straddling the junction of two main sets of blood vessels, which enter each rear limb.

  • A unilateral occlusion is when the clot blocks just one vessel from entering one leg.
  • Bilateral occlusion occurs when both leg blood vessels are blocked. This type has a much lower survival rate (between 15% and 35%) than unilateral (70% to 94%).

The thrombus cuts off blood supply to the legs or seriously reduces it, working like a plug at the junction. Without healthy blood flow, the rear legs eventually stop working, rendering your pet paralyzed at the rear. The reduced blood supply is also believed to be very painful. We all know what "pins and' needles" feels like when you've sat on your foot, slept on your hand, and so on. It's super uncomfortable, right?

Causes of Saddle Thrombus in Cats

The most common cause of saddle thrombus in cats (and other animals) is heart disease because it is also the most common cause of blood clots. A healthy heart rarely creates blood clots, and your cat can't get a saddle thrombus unless they have blood clots.

There are other causes of this kitty condition, of course. These include:

To find the underlying cause, you should give as much information to your vet as possible. Pet camera footage, notes that you’ve made, all the food, water, and treats and their packaging. The more you can tell them, the quicker a diagnosis will come.

Signs of Saddle Thrombus in Cats

The problem with saddle thrombus is that you won't know your cat has it until the clot has restricted blood flow and starts to cause problems. The symptoms come on very quickly, in the blink of an eye - because that's how fast blood clots work. One minute, they're traveling around the vessels, aortas, and veins, and the next, they're blocking a vital channel.

NCBI studies say that your pet can go from being super healthy and happy to being in high distress in a matter of moments. This is why it's so important to monitor your furry friends around the clock. Modern pet tech makes that possible. Pet cameras allow you to check in with your pets at any time, along with offering a video diary, of sorts, to provide vets with as much information and evidence as possible.

Feline saddle thrombus symptoms include:

  • Panting;
  • Rapid breathing;
  • Whimpering, crying, and being more vocal than usual;
  • Exhibiting signs of pain, such as irritability and snappiness;
  • Difficulty moving around, particularly rear legs;
  • The muscles on the rear legs are rock hard;
  • Rear legs feel cool or cold to touch;
  • Falling over/inability to stand;
  • Change to paw pad color - often paler.

Treatment for Saddle Thrombus in Cats

The sooner you get your pet to the vet, the quicker they can receive treatment, and with a saddle thrombus, those minutes really could mean life or death. There are a handful of ways that the condition can be treated, and your vet will choose a suitable approach for your pet and their specific case.

The underlying cause of the saddle thrombus needs to be figured out. For example, if your cat has cancer, the clots and other issues will continue to materialize until they go into remission and/or the cancer is completely eradicated. Alongside treatment for the thrombus itself, treatment for the underlying cause is also important.


For some cats, medication to essentially dissolve the clot(s) is effective. It usually takes a few days for the medication to take effect and fully work, and it is not always effective at all. Anticoagulants (blood thinners), aspirin, and thrombolytic (dissolving) drugs are all potential medication-based treatments.
Alongside medication to dissolve clots, your vet will probably prescribe pain relief, especially if your fur baby is suffering, which they likely are.


Once the thrombus is removed, your pet will need a little help getting back to full mobility, and physiotherapy can help just as it can with humans. This is only an option if your pet is not in too much pain and responds well.

Surgical Clot Removal

When medication doesn't work, surgery is an option to get rid of clots and saddle thrombus, but just as with medication, it's not always effective. Not only that, but the surgery itself can be dangerous, causing more issues and not resolving the original problem.

No Response to Treatment

Unfortunately, saddle thrombosis that affects both legs (bilateral) is often fatal and doesn't respond well to treatment. In such cases, complete amputation of both rear legs, or euthanasia, is suggested. These aren't pleasant options, but the alternative is extreme pain and much lower mobility. Many cats don't regain movement in their back legs even if the blood clot is dissolved future clots are prevented, and long-term or permanent damage to the nervous system or heart is common.

How Can the Emergency Fund Help with Treatment

Saddle thrombosis is a serious, life-threatening condition for cats, which is exactly what Petcube's Emergency Fund is for. For less than $1 per day, you'll get access to up to $3,000 worth of medical care for emergencies, such as saddle thrombus in cats. It doesn't matter about your cat's medical history, specific breed, or age, as long as it's an emergency, you'll be covered.

Signing up for the Emergency Fund is quick and easy, and you'll unlock access to licensed and professional vets around the clock. A quick chat with Petcube is all it takes to get the process started, and you can get an additional 27% off the cost just for being a loyal blog reader right here.


Which breeds get saddle thrombus the most?

Although any cat breed can develop this blood clot condition, it does seem to be more common in certain breeds, particularly Ragdolls with HCM (hypertrophic cardiomyopathy), Maine Coons, and potentially Sphynx and Norwegian Forest cats.

How much does saddle-thrombus cat treatment cost?

Felines are often rushed to a vet once symptoms of saddle thrombus are in full swing, so you'll need to allow for initial stabilizing medications and treatments, plus all examinations and tests. This includes blood tests, urine tests, blood flow analysis, thyroid testing, coagulation testing, chest X-rays, ultrasounds, and more. Surgery to dissolve or remove clots will cost more than $1,500, and ongoing supportive treatments, care, and medication will also need to be considered.


Saddle thrombus in cats is not a light matter. If you don't seek URGENT medical attention - within minutes, not hours - it is likely that you will face losing your precious pet. With no known methods of prevention and the chance that it could hit your pet at ANY time without any warning, it definitely makes sense to learn more about it.

If you're ever in doubt, consult with a vet. That's easier than ever with Petcube's Emergency Fund!

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