Hypertrophic Cardiomyopathy

Dedicated to McLaren, Diagnosed in Jan 2001

What is it?
It is an acquired heart disease and not thought to be genetic. There is a thickening of heart walls, causing the heart to work harder. Eventually, the cat goes into heart failure. There are medications that slow the progression of this disease. However, there is no surgical cure at this time.

Who gets it?
Note: these are just guidelines. My cat is a male American shorthair and was diagnosed at 11 months. Although the onset was earlier than normal, he is otherwise a textbook case.

Possible Signs
It may occur without warning and may be severe. It may be mistaken for possible heartworm. Unfortunately, the first sign of this disease can be a cat's premature death. Common warning signs are:

Diagnosis can usually be made after an echocardiogram, or echo for short. Diagnosis including echo costs about $300 to $350.

Treatment is usually a combination of medication. Lasix is commonly used and prevents fluid buildup by having the cat urinate the excess fluid. This drug is often not used on a long-term basis unless the cat has severe symptoms. The primary drug is used to help slow the heart. For example, my cat is on Altenolol. Aspirin (children's dosage only) may be used every third day; it is thought that aspirin may help limit blood clots which are very common with this disease. Although there is some controversy about using aspirin, it is unlikely to have harmful effects result from its use. Other drugs may be added as needed. (My cat also takes Lotensin.) I spend about $15 a month total on all of his medication.

Prognosis depends on the severity of the condition. Mild to moderate conditions may allow a cat to live 5 or 6 years; severe conditions may drastically reduce a cat's life to only a year or two. I suggest taking your cat to a specialist after the initial diagnosis. My cat was diagnosed with severe HCM and was treated aggressively with drugs. A month later, a cardio specialist reclassified it as mild to moderate, and his prognosis was much better. Try contacting a veterinary college in your home state.