Sudden painful weakness or inability to use a leg, collapse or difficulty breathing requires an emergency vet now. Phone the practice for immediate instructions. Do not wait to identify the cause at home.
What is a saddle thrombus?
Feline arterial thromboembolism occurs when a blood clot blocks an artery. A clot associated with heart disease can lodge where the main artery divides towards the hind legs; this is commonly called a saddle thrombus. It can occur in cats whose heart disease has not previously been recognised.
Possible signs include sudden severe pain and weakness or paralysis, often affecting the hind legs. Other limbs can be involved. See Cornell’s explanation of HCM and clot complications.
Act on the symptoms
You do not need to confirm a clot, check a leg pulse or see every possible sign before seeking help. An injury or another illness may look similar and also need urgent treatment. Tell the emergency practice when the change started, which limbs are affected and whether breathing looks abnormal.
Follow the practice’s transport advice and keep handling to a minimum. Do not give human painkillers or start an anti-clotting medicine yourself. Bring details of prescribed medicines if readily available, without delaying departure.
Treatment and outlook
Veterinary care addresses pain, circulation and any associated heart or breathing problem. The outlook varies with the individual cat and severity of illness; recovery and recurrence are both possible. The treating team should discuss likely outcomes and care options with you. Tufts’ guide to heart disease in cats describes this complication.
For cats already diagnosed with heart disease
Ask your vet whether clot prevention is appropriate and which symptoms require an emergency visit. Home observations and consumer monitors cannot establish that a cat is free of clot risk. Follow prescribed treatment and keep recommended follow-up appointments.
This article explains warning signs; it is not a way to diagnose or treat a clot at home.
