Dilated cardiomyopathy in cats is a disease in which the chambers of the heart enlarge, or dilate, as a result of a thinning of the muscle walls of the heart. This weakens the heart and leads to less powerful contractions, which can ultimately cause congestive heart failure.
Risk Factors for Dilated Cardiomyopathy
Dilated cardiomyopathy, or DCM, occurs as the result of a deficiency of the amino acid taurine in a cat's diet. DCM, once a common cat disease, has grown incredibly rare in recent years as commerical pet food companies now provide a wide range of nutritionally balanced cat foods. Even more rarely, DCM may occur idiopathically, which means without discernible cause.
DCM can affect cats aged two and older, and it seems to strike male cats more often than females. The average age of onset is ten years old. Dilated cardiomyopathy is a serious and often deadly illness.
Symptoms of DCM in Cats
Cats in the beginning stages of dilated cardiomyopathy may seem to lack energy and display lowered activity levels. They may lose their appetites and experience episodes of weakness, even leading to collapse. They might experience shortness of breath and coughing, which are symptoms of congestive heart failure, a common complication of DCM. If congestion in the chest cavity becomes severe, the cat's abdomen may become swollen and distended.
Cats with DCM are vulnerable to thromboembolism, or blood clots that obstruct blood vessels. If this occurs, your cat may experience sudden, severe pain and even paralysis in the affected limb. Usually thromboembolism affects the hind legs.
Diagnosing and Treating DCM in Cats
Your vet will need to perform a wide range of tests in order to confirm a diagnosis of dilated cardiomyopathy and rule out other diseases that produce similar symptoms. Your vet will need your cat's complete medical history, if possible, and he'll perform a physical exam and listen closely to your cat's heart and lungs. He'll take chest X-rays and perform an EKG.
Your vet will perform a complete blood count and measure your cat's arterial blood pressure to determine the strength of his heart's contractions. He may perform an ultrasound of the heart and check your cat's taurine and thyroid hormone levels. If thromboembolism, congestive heart failure or other complications have occurred, your vet will perform serum biochemistries to determine how severe these problems have become.
Treatment for feline cardiomyopathy varies depending on how far the condition has progressed. Your cat will need to be put on a low sodium diet and may need taurine supplements. If your cat's heart is also beating on an irregular rhythm, which sometimes occurs, then your vet will prescribe drugs to help regulate heart rhythm. Diuretic, enzyme inhibiting drugs can help relieve the symptoms of congestive heart failure and anticoagulant drugs can help relieve thromboembolism and prevent the dangerous complications that can occur as a result of blood clots traveling through your cat's body.