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Hypertrophic Cardiomyopathy in Cats

Hypertrophic cardiomyopathy is the most common heart disease seen in cats. Our Bonita Springs vets explain the symptoms and what you can do if your cat is diagnosed with feline hypertrophic cardiomyopathy.

What is Feline Hypertrophic Cardiomyopathy?

Feline hypertrophic cardiomyopathy, the most common type of heart disease seen in cats, causes thickening of the heart muscle and decreases the efficiency of the cat's heart. Some cats can show little to no signs of the illness, especially earlier on in the disease. If a cat shows no symptoms, the disease can go unrecognized and lead to congestive heart failure.

What Causes Hypertrophic Cardiomyopathy in Cats?

The definitive cause of feline hypertrophic cardiomyopathy is unknown, although some cases of cardiomyopathy, especially restrictive cardiomyopathy, appear to be congenital (present from birth).

Middle-aged male cats tend to be more commonly affected.

Kidney failure can cause hypertension and cardiomyopathy in cats.

What Are the Signs of Hypertrophic Cardiomyopathy in Cats?

Signs of feline hypertrophic cardiomyopathy can vary from no symptoms at all to lethargy and rapid or labored breathing. Other signs of feline HC can include sudden weakness, collapsing episodes, and sudden death due to disruption in the heart's rhythm.

In some cases, signs of congestive heart failure specific to the left side, including fluid accumulation in the lung, may occur. Signs of this may include lethargy, decreased activity level, rapid and/or labored breathing, and heavy breathing through the mouth during exercise or excitement.

In some cases left and right-sided congestive heart failure develops with fluid accumulation inside the chest or abdominal cavity. This causes your cat to really struggle to breathe and emergency veterinary care should be sought immediately.

Cats with very large heart chambers run the risk of a blood clot forming. If this occurs and it enters circulation, weakness or paralysis (usually of the hind legs) may develop.

How is Hypertrophic Cardiomyopathy in Cats Diagnosed?

A physical examination by a veterinarian may reveal abnormal heart and lung sounds, a heart murmur, or irregularities in heart rhythm that can lead to a suspected diagnosis of the disease. Chest X-rays, electrocardiograms, and echocardiograms are often used to confirm a diagnosis and determine the severity of the case.

A routine physical exam and any number of other tests may be recommended every six to twelve months to look for any progression of disease in cats who aren't showing any clinical signs.

How is Hypertrophic Cardiomyopathy in Cats Treated?

Treatment plans for feline hypertrophic cardiomyopathy vary depending on the severity of each case.

Asymptomatic cats may not require medical therapy, but routine reevaluations will often be recommended. Other cats will be prescribed medications to slow the heart rate and encourage relaxation of the ventricles (pumping chambers). If arrhythmias or congestive heart failure signs are present, additional medications may be required.

Since this disease can be progressive, medications and dosage may be adjusted over time. Therapy is always tailored to the individual needs of each patient.

Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.

Contact our Bonita Springs vets as quickly as possible if your cat is exhibiting any signs of feline hypertrophic cardiomyopathy. 

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