Hypertrophic Cardiomyopathy in Cats
Dilated cardiomyopathy occurs when the heart muscle loses its tone and
becomes flaccid. The heart chambers overfill, the walls of the ventricles
become thinner, and the chambers enlarge. One cause of dilated cardiomyopathy
is taurine deficiency. Taurine is an essential amino acid present in high
concentrations in animal tissue. Feeding dog food or a grain-based cat food could lead to taurine
deficiency. Most commercial cat foods are currently supplemented with taurine.
Dog foods are not, so a cat eating dog food has a high risk of developing
Another cause of dilated cardiomyopathy is myocarditis, which is
inflammation of the heart muscle. Viruses and autoimmune diseases have been
implicated as the cause of myocarditis in humans, although its cause is unknown
Dilated cardiomyopathy is often a rapid-onset disease that progresses over
two or three days as the heart begins to fail. The most frequent sign is
labored breathing at rest. The cat often sits with his head and neck extended
and elbows out, straining to take in air. Cool feet and ears and a body
temperature below normal are signs of poor circulation. Heart murmurs are
common. The pulse is often rapid and thready and may be irregular or even slow.
Loss of appetite, rapid weight loss, weakness, fainting attacks, and
crying out spells often accompany the signs. A clot blocking the vascular
pathway to the rear legs may be the first sign. Echocardiography is the best
method for diagnosing dilated cardiomyopathy.
Treatment: Treatment of dilated cardiomyopathy is directed at correcting any
taurine deficiency and controlling fluid retention. Fluid retention is best
managed using diuretics such as furosemide (Lasix). Cats with taurine
deficiency cardiomyopathy who survive the first week of supplementation have an
increased chance for survival, but it can take four to six months for the heart
muscle to heal.