HCM, or hypertrophic cardiomyopathy, is a confusing and frustrating disease to understand. Stated basically, it is a common heart disease found in cats of all breeds and backgrounds where the left ventricle becomes enlarged. Cats can appear healthy (asymptomatic) or they can show signs of the disease which require an echocardiogram to give an accurate diagnosis. The difficult part of this disease is that there is no genetic test available to determine if a cat is a carrier. So a breeder, such as myself, scans their cats every year to monitor their cat’s heart. Maybe the scan is normal for the first two scans – so we keep using that cat in our breeding program, believing they are negative for HCM. Then suddenly the third scan shows signs of HCM. We have inadvertently “passed” HCM on to another generation of offspring without knowing it. My point is this – just because an adult cat is scanning negative for HCM does not guarantee the cat will never develop HCM in its lifetime, or that its kittens will not develop the disease. These are living creatures, and just like people, there is no “lifetime guarantee”.
At a recent visit with my cat’s cardiologist, I was able to ask a few questions about HCM I felt were important to clarify. Below are his answers and opinions:
How common is HCM in Sphynx versus other cats?
About average. He sees just as many house cats with HCM as Sphynx, or any other breed for that matter. Generally owners only bring sick cats, or cats referred by their veterinarian for suspected heart issues.
What are the visible signs of HCM?
Increased breathing, fatigue and paralysis.
What age should I test my cat for HCM?
You should test the cat right away if a cardiac problem is suspected. Otherwise if you decide to test, a good age to start would be 2-3 years old. Most HCM positive scans this particular cardiologist sees are in cats over 7 years of age.
How often should I test my cat that is in a breeding program?
Test the cat at 2-3 yrs old. If no signs of HCM are noted, test again every other year. Scanning annually is also an option.
Once diagnosis of HCM is made, what is the life expectancy of the cat?
It depends on the severity and age of the cat. Some cats can live for many years after their diagnosis and others aren’t as lucky.
The article below explains HCM in detail and is generally accepted by the
HCM: Should I Be Concerned