Biology Reference
In-Depth Information
TREATING CONGENITAL HEART DISEASE
About 2 percent of cats are born with congenital heart defects. In addi-
tion to problems with the valves, which I have already discussed, there
may be holes in different chambers of the heart or strictures in blood
vessels leaving the heart. Some types of congenital heart diseases can be
surgically corrected and the cat can live a normal life. Other types may
be monitored throughout a cat's life but never cause any clinical signs,
and still others may be life-threatening.
Heart surgery is tricky in any animal, but due to the small size of
cats, it can be especially risky and expensive. Most congenital disease
involves defects in the structures of the heart, and these problems gen-
erally do not respond to medication.
HEART MUSCLE DISEASE
The pumping action of the heart is achieved when the different cham-
bers of the heart constrict in a specific sequence (see page 162). The
heart itself is primarily composed of muscle tissue, and diseases can
affect this tissue.The medical term for heart muscle disease is
cardiomy-
opathy
.There are three main types:
1.
Dilated cardiomyopathy (DCM)
2.
Hypertrophic cardiomyopathy (HCM)
3.
Restrictive cardiomyopathy (RCM)
Cardiomyopathy should be suspected in the sudden death of an
otherwise young, healthy animal. Often there are no obvious clinical
signs of heart muscle disease, so the problem may not be detected or
suspected before heart failure occurs.
Echocardiography is needed to definitively diagnose any type of
cardiomyopathy. It is also used to monitor the progression of the disease
and the cat's response to therapy. If your veterinarian does not have an
ultrasound machine, a specialist with a mobile unit may be asked to
come to the clinic or you may be referred to a specialty center that has
this equipment.
Dilated Cardiomyopathy
In dilated cardiomyopathy (DCM), the heart muscle stretches out and
becomes a thin, flaccid sack that is unable to contract properly. Blood is
not effectively pumped between the chambers or out of the heart.
