Feline Cardiomyopathy
Feline cardiomyopathy is a disease of the heart muscle which results from either a very thickened heart muscle, resulting in very small heart chambers (hypertropic cardiomyopathy) or a very dilated (stretched) heart muscle with very large heart chambers (dilated cardiomyopathy).
Both forms result in a heart that is unable to function properly in pumping blood throughout the body.
A major complication of this condition is the tendency to develop blood clots in the heart chambers. These blood clots escape the heart and travel through the arteries until reaching a point too small for them to continue. The clot then obstructs blood flow to the rest of the body from that point on.
The most common location of this obstruction is where the aorta splits to go down each rear leg. When this happens, the cat suddenly is in great pain, becoming quickly paralyzed in the rear legs. This is the first sign of cardiomyopathy in many cats.
Causes Of Feline Cardiomyopathy:
Causes of this condition are often unknown, but the following medical problems have been identified as potential causes:
- Taurine Deficiency: Taurine in an essential amino acid and was found to be deficient in many commercial cat foods before being identified as a problem. Cat food manufacturers have now corrected the problem since taurine was identified as being important and deficient.
- Hyperthyroidism: A condition resulting from an abnormal thyroid gland can also cause the problem. The disease develops slowly over a long period of time before clinical signs become evident. Cats have the ability to hide the disease until the very late stages. For this reason, many cases are not discovered until very late in the disease process.
- There may be a genetic component predisposing some cats to this disease also.
Symptoms Of Feline Cardiomyopathy:
Early signs include inactivity, lethargy, and poor appetite. Severe signs of heart failure may not become evident until just before death.
The major sign of heart failure in the cat is labored breathing.
As noted above, blood clots lodging in major arteries are often the result of feline cardiomyopathy as well. One of the primary signs of blood clot formation is paralysis of the rear legs.
Diagnosis Of Feline Cardiomyopathy:
Diagnosis of feline cardiomyopathy involves a thorough physical examination by your cat's veterinarian.
Ultrasound examination of the heart is often necessary to confirm the condition.
ECG’s and chest x-rays can also be useful.
Your cat's veterinarian may also recommend a basic blood screen to make certain medications chosen to treat the condition are safe for your cat. A thyroid screen will likely be part of the blood screen recommended, to test for hyperthyroidism.
A heartworm screen may also be recommended, as heartworms can cause similar types of symptoms.
Your cat's veterinarian may recommend testing your cat's blood pressure, because hypertension (high blood pressure) is a common finding with heart disease.
An ocular (eye) examination may also be recommended, to check for eye damage caused by hypertension.
Treatment Of Feline Cardiomyopathy:
Treatment will not cure the condition but may prolong the quality of life for your cat for some time. Treatment is directed at helping the heart function easier and must be tailored to your cat.
Medications commonly used in the treatment of cardiomyopathy are drugs which help to control the heart rate, such as diltiazem, altenolol, or propanolol.
Diuretics, such as furosemide or spironolactone, may be used to help control the fluid "back-up" in the lungs and other tissues which can result from heart failure.
Anticoagulant drugs, such as aspirin, warfarin, or coumadin, may be used to help prevent thrombus (blood clot) formation.
In addition to medications, special diets containing restricted amounts of sodium may be recommended by your cat's veterinarian.
