Dumpling was a magnificent Maine coon cat, his owner’s pride and joy. Almost 16 years old, he still looked like a vigorous feline in his prime, until one evening when he suddenly let out a peculiar yowl and began flailing on the floor. His owner quickly determined that Dumpling, who was salivating, panting, and crying in distress, was unable to move his hind legs. She contacted the veterinarian covering emergency calls that night and arranged to be seen immediately.
The diagnosis was made promptly. Dumpling’s hind feet were cold and his body temperature was three degrees below normal. His pads, normally a vibrant, healthy pink, were purple. Where one would usually feel blood bounding through the femoral arteries on the inner aspect of his thighs, there were no palpable pulses. Dumpling had feline aortic thromboembolism, also known as FATE, or “saddle thrombus.”
Thrombus: from the Greek thrombos, meaning “lump, piece, curd of milk, clot of blood.” Embolism: from the Greek embolimos meaning “insertion” or embolos meaning “wedge, or plug.” Thromboembolism refers to a clot of blood or other material occluding a blood vessel.
In FATE, a clot forms in the heart, then breaks loose and goes shooting down the aorta (the major blood vessel supplying the body.) At the pelvis, the aorta forks like a Y, one branch carrying blood to each hind leg. The clot gets caught at this fork, lodging like a saddle on the Y and occluding blood flow. The extent of the occlusion depends on the clot’s exact size and location. Although a small percentage of FATE cases have normal hearts, in the vast majority, the initial clot forms because of some kind of underlying cardiac pathology. The fact that Dumpling had no previous history of heart problems is irrelevant. In more than seventy-five percent of FATE cases, the saddle thrombus is the first clinical sign of the cat’s cardiac disease.
FATE can occur at any age, but is most common in middle-aged cats. Males seem to be affected more than females as do certain breeds including Abyssinian, Birman, Ragdoll, Tonkinese…and Maine coon cats. As many as half of affected cats survive the initial episode, and may regain partial to total function of their legs over the next month or so, but half never make it out of the hospital after the first event. For those that do survive, most eventually succumb to cardiac disease, to complications from the initial clot, or to a second episode of FATE.
Dumpling’s mother had serious decisions to make. She could take him to a 24-hour referral facility off Island with veterinary specialists, round-the-clock staff, and access to the most sophisticated treatment and state-of-the-art diagnostic tools. But this would be very stressful for him, and with such a poor prognosis…well, if he wasn’t going to make it, she wanted him to be home, with her.
The doctor started him on a standard FATE treatment protocol which includes anticoagulants, analgesics, and vasodilators, medications intended to prevent further clots, treat pain, and relax the blood vessels in hopes the clot will move. Although good in theory, in practice our current protocols have unfortunately not proven very effective. People with thromboembolic disease are sometimes treated with medication such as streptokinase which may dissolve clots, but such treatment is prohibitively expensive for use in cats. Surgery to remove clots has not been widely successful in cats either. So we do what we can and hope for the best.
The next morning Dumpling’s mom brought him to see me. He was amazingly alert and appeared pain-free. But those feet. Blue. Cold. No pulses. I shook my head dejectedly while Dumpling purred and rubbed his cheek against his owner’s hand.
“His temperature is back up to normal,” I said. That was good. “His heart sounds fine, but that doesn’t rule out cardiac disease. What the vet told you last night is still the case today. If you don’t go to the specialist, we could do a cardiac work-up here and continue this treatment protocol.”
I took a deep breath, knowing I should be brutally frank. “If he doesn’t regain circulation soon, his legs will actually start to die, and he will get very sick. If he does regain circulation, there’s still a high probability of another clot or heart failure.”
Dumpling cocked his handsome head to one side and gazed at me quizzically. I could see why his owner was struggling with the idea of euthanasia. The pain and distress exhibited at the outset had resolved and, from the hips forward, Dumpling was the same old happy cat. Considering his age and the poor prognosis, his mom decided not to put him through further diagnostics but as long as he wasn’t in pain, she wanted to continue treatment on an outpatient basis.
Four days later, Dumpling’s feet were warm, pink, and swollen. I could detect a slight, thready pulse in his left leg. He wasn’t eating much, but he was actively pulling himself around the house. Other than the picky appetite, his demeanor seemed normal — affectionate and purring.
As Dumpling regained circulation, there was a whole new set of potential complications we might encounter due to “reperfusion injury,” but for now, he seemed to be enjoying his quality home time with his mom. Maybe he would be one of the lucky ones with no underlying cardiac disease who regain circulation and function. Life expectancy in that case would average another six to seven months, maybe more.
But two days later, the picture changed dramatically. Dumpling’s breathing became labored and it was obvious from his expression that he was anxious and in pain. Aggressive diagnostics and treatment might help, but that was a long shot. His prognosis was rapidly worsening. Staying home with outpatient care was no longer a humane option.
After a long heart-to-heart with everyone involved, including Dumpling, we said good-bye that day and let him go peacefully. He had been a magnificent cat, but we aren’t always masters of our fate.