Understanding HCM Testing in Cats: A Guide for Breeders and Cat Owners

Hypertrophic Cardiomyopathy (HCM) is a common heart condition in cats that can lead to serious health issues. For breeders and cat owners alike, understanding HCM and the importance of testing for this condition is crucial in avoiding and managing this heartbreaking condition. This post aims to provide comprehensive insights into HCM testing, particularly for those new to cat breeding or looking to own a breed prone to HCM.

What is HCM?

Hypertrophic Cardiomyopathy is a disease that causes the heart muscle (myocardium) to thicken abnormally. This thickening can make it difficult for the heart to pump blood efficiently, leading to heart failure and other complications. HCM is the most common heart disease in cats and can affect all breeds, though certain breeds like Maine Coons, Ragdolls, and British Shorthairs (the best breed, of course) are more predisposed.

Why is HCM Testing Important?

1. Early Detection: Early identification of HCM can help manage the disease more effectively. With appropriate medical care, cats with HCM can lead longer, healthier lives.

2. Breeding Decisions: For breeders, testing for HCM is crucial to ensure they are not passing on the genetic predisposition to future generations. This helps in maintaining the health and integrity of the breed. Responsible cat breeders do not want to put kittens or future cat owners through the stress and heartbreak of a HCM diagnosis. Although testing does not eliminate the risk of producing a kitten with HCM, it will reduce it. At Bonbelle, we regularly test every breeding cat.

3. Peace of Mind: Knowing the HCM status of your cat provides peace of mind. HCM can cause sudden death or unusual symptoms. Whether you're a breeder or an owner, it’s comforting to know you’re taking steps to be aware of your cat's heart health and follow the proper treatment if HCM is present.

Methods of HCM Testing

1. Echocardiogram: This is the gold standard for diagnosing HCM. An echocardiogram is an ultrasound of the heart performed by a veterinary cardiologist. It provides detailed images of the heart’s structure and function, helping to identify any abnormalities. This is how we test our breeding cats.

2. Genetic Testing: Genetic tests are available for specific mutations known to cause HCM, particularly in breeds like Maine Coons and Ragdolls. While a positive genetic test indicates a predisposition to developing HCM, it doesn’t confirm the presence of the disease. Conversely, a negative test doesn't rule out HCM entirely, as other, yet unidentified, mutations may be responsible. It is always best to get an echocardiogram in addition to genetic testing results. There is currently no accurate test for the genetic predisposition of HCM in British Shorthair cats.

3. proBNP Testing: The proBNP test measures the level of a specific peptide (B-type natriuretic peptide) that is released by the heart when it is under strain. Elevated levels can indicate heart disease, including HCM. While not a definitive test for HCM, it is a useful tool in conjunction with other diagnostic methods to assess heart health.

When Should You Test?

- Breeding Cats: All breeding cats should undergo HCM testing before being used in a breeding program. Most breeders and veterinarians suggest echocardiogram screenings around one year old. Regular follow-up testing is also recommended, as HCM can develop later in life. Yearly testing is best, but some breeders suggest testing every few years after the age of 5.

- Pet Cats: If you own a breed prone to HCM or if your cat shows symptoms of heart disease (such as lethargy, difficulty breathing, or fainting), consult your veterinarian about HCM testing.

What to Do if Your Cat Tests Positive

1. Consult a Specialist: If your cat tests positive for HCM, consult with a veterinary cardiologist to develop a management plan tailored to your cat’s needs.

2. Medication and Lifestyle Changes: Depending on the severity, your veterinarian may prescribe medications to help manage the condition. Lifestyle changes, such as a low-sodium diet and avoiding stress, can also be beneficial.

3. Regular Monitoring: Regular check-ups and echocardiograms are essential to monitor the progression of the disease and adjust the management plan as needed.

Conclusion

HCM is a serious but manageable condition in cats. Through proactive testing and informed breeding practices, the incidence and impact of HCM can be significantly reduced. As a breeder, ensuring your cats are tested for HCM not only promotes the health of your breeding lines but also contributes to the overall well-being of the breed. For pet owners, understanding and testing for HCM ensures you can provide the best care for your kitties.

Taking steps to test for HCM is a vital part of responsible cat ownership and breeding. By staying informed and proactive, you can help ensure a healthy, happy life for your cats.

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About the Author

Amelia is a passionate cat breeder and the owner of Bonbelle Cattery, specializing in the wonderful British Shorthair breed. With a background in show dogs, and a new-found passion for reputable cat breeding, Amelia is dedicated to promoting the health and well-being of British Shorthairs through responsible breeding practices and continuous education.