Aortic Thromboembolism in Cats

Aortic thromboembolism describes what happens when a blood clot forms in or travels to the aorta — the body's largest artery — and then blocks one or more of the smaller arteries that branch away from it. In cats, this most often affects the arteries supplying the hind legs. The blockage cuts off blood flow, and the affected limb or limbs lose function suddenly. Owners typically notice that their cat cannot use one or both back legs, often quite abruptly. The affected legs may feel cool or cold to the touch, and the cat may vocalise or breathe rapidly. The presentation can appear after a period of seeming normality, or may emerge in a cat already known to have heart disease. Many cats with this pattern have underlying heart muscle disease that created the environment in which a clot could form. This page explores the signals that may prompt concern, what is happening in the circulation and the heart, how the condition is investigated, and the range of approaches that exist. The goal is to orient understanding, not to direct decisions.