Heart (Aortic) Blood Clot In Cats

Feline aortic thromboembolism (FATE) is a serious and sometimes fatal complication of heart disease in cats

It affects as many as 25%of cats with hypertrophic cardiomyopathy, a common feline heart condition. FATE usually strikes without warning; in fact it may be the first and only sign of heart disease in some cases.

What is a feline aortic thromboembolism?

Feline cardiogenic arterial thromboembolus (ATE), also known as "saddle thrombus," is a devastating complication of heart disease in cats. Heart disease can cause disturbances in blood flow through the heart that can lead to the formation of blood clots.

In cats, these blood clots can travel downstream and become lodged in the femoral arteries

the main arteries that provide blood flow to the hind limbs. When a saddle thrombus occurs, there is a loss of blood flow to the hind legs causing pain, decreased pulses, cold limbs and paralysis.

Who is at risk of aortic thromboembolism?

Cardiogenic arterial thromboembolus occurs most commonly in cats with advanced heart disease and is rarely seen in dogs. While certain breeds are more prone to heart disease, like the Maine Coon, Ragdoll, Sphynx, Persian, and Abyssinian; saddle thrombus can occur in cats of any breed or age, although it is usually seen in cats 8 years and older.

Symptoms of aortic thromboembolism

*Vomiting

*Paralysis

*Pain (especially in the legs)

*Abnormalities with gait and/or lameness

*Difficult breathing (e.g., tachypnea)

*Unusual barking or anxious temperament

*Bluish or pale nail beds and food pads

*Hypothermia

Most cats with this condition require immediate intensive care & hospitalization to prevent complete heart failure

Hospitalization is also necessary to minimize the stress and pain associated with this disease. Cats with breathing problems require oxygen therapy to reduce the stress of rapid breathing and to allow achieving required levels of oxygen in the blood.

Thrombolytics medications, which are used to dissolve the blood, are essential for treatment.

Cats that do not respond to conventional treatment, however, will require surgery to remove the blood clot. Your veterinarian will also give pain killers to reduce the severe pain associated with this disease.

Available treatments have included anti-thrombotic drugs or surgery to remove the clots but they have not been very successful

Many anti-thrombotic drugs have been used to prevent recurrences in cats with heart disease. Recent studies indicate that clopidogrel (Plavix) appears to be superior to aspirin for the prevention of recurrent ATE in cats. Cats may recover function in their rear limbs but unfortunately remain at high risk for developing additional aortic thromboembolisms.

Unfortunately, the prognosis for most cats with aortic thromboembolism is not good.

Even with treatment, clots can again develop and block the aorta. If blood supply to the legs are not restored quickly, permanent muscular abnormalities may develop in the affected limb.

Cats recovering from aortic thromboembolism

should not be allowed to move and should be placed in a stress-free environment, away from other pets and active children

Severe pain is a common symptom associated with this disease

and many cats find it difficult to urinate due to problems with their posture. In addition, most affected cats find it difficult to eat and may require new foods to tempt the palate. This lack of appetite (anorexia) may lead to further complications.

Despite treatment, the prognosis is poor and many cats are euthanized due to recurrences and poor quality of life

However, newer anti-thrombotics that will hopefully help cats with aortic thromboembolisms live longer, are currently being evaluated and may be available in the next five years.

Aortic thromboembolism is an unfortunate complication of heart disease

Since early heart disease is asymptomatic, it is best to take your cat to the veterinarian at least once a year to screen for heart disease.

Starting treatment for heart disease earlier can improve quality of life and extend life expectancy.

If you think your cat may have or had a saddle thrombus see your veterinarian as soon as possible.