Feline Arterial Thromboembolism

What is Feline Arterial Thromboembolism (FATE)?

  • Arterial Thromboembolism in cats is one of the most devastating consequences of cardiac disease in the feline patient.
  • It occurs secondary to an enlarged left atrium seen commonly in feline heart disease resulting in poor blood flow.
  • Blood clots can form within the left atrium. These clots (emboli) can break loose and enter the body’s circulation resulting in complete blockage of blood flow to limbs, other organs or the brain.

What happens with Feline Arterial Thromboembolism?

  • Most commonly the clot will exit the heart, travel down the aorta, and lodge in the iliac arteries resulting in complete interruption of blood flow to the rear legs.
  • Cats will develop a sudden onset of weakness and an inability to use the rear legs often accompanied by pain, vocalization, and respiratory difficulties.
  • This is a medical emergency and prompt veterinary care should be obtained.
  • Clots can potentially travel to any part of the body.
  • Clinical signs can vary including front limb lameness, inappropriate mentation, or even sudden death.

How is Arterial Thromboembolism in cats prevented?

  • If your cat has an enlarged left atrium, your cardiologist may prescribe medications to help prevent the occurrence of an inappropriate blood clot (most commonly Aspirin and/or Clopidogrel (Plavix)).
  • Choice of medication is dependent on the individual patient’s risk factors.
  • There are likely certain genetic factors that affect your cat’s risk for forming blood clots. Some of this is sadly unpreventable and beyond current medical therapies.
oval clot
Echocardiogram revealing an oval clot within the outpocketing of the left atrium known as the left auricular appendage (outlined).
image of heart with labels
Figure of heart depicting thickened left ventricular walls (LV), enlarged left atrium (LA) and clot within left atrium.

What is the prognosis?