Arterial Thromboembolism (ATE) is a complication of heart disease or hypertrophic cardiomyopathy (HCM) in cats that strikes without warning and is often times fatal. Age of occurrence for thromboembolism ranges from 1 to 20 years (mean, 7.7 years; median, 10.5 years) in one report. It is also more prevelant in males than females.
It happens when a blood clot or clots are released from the heart and lodges somewhere in the cats body restricting blood flow. Normally the clot will lodge in the hind quarters restricting blood flow to one or both of the back legs. Depending where the clot lodges itself it can also restrict blood flow to one or both of the front legs, but most commonly the back legs are affected. This is a devastating occurance for the cat as it happens quite suddenly and can be extremely painful.
There is no diagnostic testing other than ultrasound that would lead one to supect any clots in the heart. If a cat is suspected of having heart disease an ultrasound should be done.
The odds of the cat surviving and regaining the use of its legs is around 30%. Although many recover from this, the average life expectancy after recovery is less than one year.
Often times a cat owner will find its cat limping and assume it injured its paw somehow, which is often time the case. But if the cat loses complete control of any of its legs it should be rushed to the hospital immediately and without hesitation. Time is of the essence it situations such as this.
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