This is characterized by the passing of a blood clot (embolus) from the left
side of the heart into the general circulation, where it becomes lodged in an
artery. The resulting obstruction to the flow of blood leads to clotting of the
The most common site for blockage is the point at which the abdominal aorta
branches into the main arteries that supply the rear legs. Arteries elsewhere
in the body can be affected, particularly in the kidneys. Diagnosis of the rear
limb problem can be based on signs such as rear limb paralysis, swollen muscles, the
absence of a pulse in the groin, and blue nails due to cyanosis. If the renal
arteries are blocked, acute kidney failure may result. If a
cerebral artery is blocked, seizures may occur. Cats
with thrombi can be in quite serious pain.
Some cats just won’t give peace a chance. There are several reasons that cats might not get along. The most common is undersocialization—a lack of pleasant experiences with other cats early in life. If your cat grew up as the only cat, with little or no contact with other felines, he may react strongly when he’s finally introduced to another cat because he’s afraid of the unknown, he lacks feline social skills, and he dislikes the disruption to his routine and environment. Cats tend to prefer...
Formation of a blood clot in the heart and subsequent arterial thromboembolism occurs in about
half of all cats suffering from cardiomyopathy. It may be the first indication
of heart disease. Suspect this possibility if your cat experiences the sudden
onset of weakness in the rear legs. Look for cold legs, bluish skin, and faint
or absent pulses in the groin. One leg may be more severely blocked than the
other. The colder leg with the weaker pulse is the more severely affected.
Ultrasound can be very useful in localizing all potential areas of
Treatment: This depends on the severity of the blockage. Your veterinarian
can prescribe medications to try to dissolve the clot. Heparin seems to be the
most useful drug for this condition. Aspirin may also be used, and a new
product called Fragmin, which is a molecular weight heparin (a version of
heparin that is smaller in size - molecular weight - than standard heparin),
may also be useful, but it is very expensive and is not approved for use in
cats at this time. Clopidogrel is currently being tested at Purdue University
to see if it will reduce the recurrence rate of thromboembolism. Surgery has
not been found to have a high success rate.