Last Sunday, Pavel seemed to get a cramp in his back leg. It was bothering him and he kept shaking it. It seemed to annoy him but it didn’t last more than 10 minutes or so. Then, yesterday, it happened again, except now he was yowling in pain and couldn’t stand on his back legs. We managed to get him seen by our vet. The news was devastating. He had a feline aortic thromboembolism, or a saddle thrombus.
A saddle thrombus is a blood clot that cuts off blood supply to the back legs. The clot forms in the heart, gets pumped into the aorta, then travels in the bloodstream until it reaches the junction leading to the arteries in the back legs. It lodges at the junction and cuts off blood supply to the legs. Without blood, the back legs become paralyzed and extremely painful.
Saddle thrombi are most common in cats with heart disease (which we knew Pavel has but seemed to be in stable condition). This is because cats with heart disease often develop large clots inside their heart that release small clots into the blood stream. Sadly, outlook for a cat with a saddle thrombus is very poor – it’s an extremely serious condition that most cats don’t recover from. The first 10 days are critical.
A third of cats that recover from a saddle thrombus develop the condition again, and their symptoms may not completely resolve i.e. they may be left with some dysfunction in their back legs and will likely need ongoing treatment for the rest of their life to prevent further blood clots forming, and also for any underlying problems such as heart disease.
For now, he’s stable. He’s mobile, which is good. He’s not in pain. As long as he doesn’t throw another clot.. But there’s no way of knowing. So for now, we watch. We hope, and we book him in to the cardiologist for a full work-up.