Feline-Hypertrophic-Cardiomyopathy

Facts: Feline Hypertrophic Cardiomyopathy

What is Feline Hypertrophic Cardiomyopathy?

Hypertrophic Cardiomyopathy (HCM) is a heart disease characterized by thickening of the muscle wall of the heart. As the muscle wall thickens, the filling chambers of the heart become smaller. In severe end-stage HCM there is little ability for the heart to fill and pump normally or efficiently.

Who usually has HCM?

It is seen most often in middle-aged to old-aged male cats. However, any age or sex can get cardiomyopathy. It is thought to be genetic in origin.

What are symptoms of HCM?

The severity of symptoms can vary from cat to cat. Some cats may show no symptoms at all. Sudden death is not unusual in asymptomatic undiagnosed cats. These cats may only develop symptoms during a stressful situation such as a visit to the Veterinarian, bathing, or dental cleaning when their heart rates are increased and the heart is unable to compensate.

Other symptoms can be mild or variable:

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Lack of appetite

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Gagging or coughing

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Weakness

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Breathing difficulty

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Reluctance to move around

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Fainting

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Rear limb paralysis

How is HCM diagnosed?

Radiographs

These will often show a characteristic “Valentine” shape to the heart. Radiographs can also help show the presence of any pulmonary fluid. Sometimes chest x-rays look completely normal and they certainly cannot reveal the thickness of the heart muscle.

Ultrasound

Cardiac ultrasound also known as echocardiogram is the most definitive method to diagnose HCM. This will show the thickness of the heart wall muscle and the contractility of the heart.

Electrocardiogram

Electrocardiogram or ECG will show the electrical rhythms of the heart. In cardiomyopathy it often shows gallop rhythms and rates over 200 bpm.

How is HCM treated?

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Beta Blockers (Atenolol)

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Calcium Channel Blockers (Diltiazem)

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Ace Inhibitors (Enalipril)

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Diuretics (Lasix)

It is important that any underlying condition be treated as well. Common diseases seen in association with HCM include hyperthyroidism and hypertension.

Can HCM be cured?

There is no cure for HCM. The goal of treatment is to improve the cat’s quality of life. The prognosis varies depending on disease progression and severity of symptoms.