Siberian cats can develop Hypertrophic Cardiomyopathy (HCM), just like any other breed of cat. While HCM can occur in any breed or mixed-breed cat, certain breeds, including the Siberian, have been found to have a slightly higher prevalence of the condition.

​

In Siberians, HCM is believed to have a genetic component, although the exact inheritance pattern and genetic mutations involved are not fully understood. Responsible breeders often screen their breeding cats for HCM and other hereditary health conditions to minimize the risk of passing on predisposing genetic factors to offspring.

​

While Siberians are generally considered healthy and robust, regular veterinary check-ups, including cardiac evaluations, are important for detecting and monitoring any signs of heart disease, including HCM. Early detection and intervention can help manage the condition and improve the cat's quality of life.

​

 What is Hypertrophic Cardiomyopathy?

Hypertrophic Cardiomyopathy (HCM) is a common heart condition in cats characterized by the thickening (hypertrophy) of the heart muscle, specifically in the walls of the left ventricle, which is the chamber responsible for pumping blood out to the body. This thickening can impair the heart's ability to function properly, leading to various symptoms and complications.

​

Causes:

The exact cause of HCM in cats is not fully understood, but it is believed to have both genetic and environmental factors. Certain genetic mutations have been identified in some cat breeds, predisposing them to HCM. However, HCM can also occur spontaneously in cats with no known genetic predisposition.

​

Symptoms:

Symptoms of HCM can vary widely and may include:

• Difficulty breathing (dyspnea)

• Rapid or labored breathing

• Weakness or lethargy

• Decreased appetite

• Fainting or collapsing episodes

• Sudden death, often due to arrhythmias or heart failure

​

Some cats with HCM may not show any obvious symptoms, especially in the early stages of the disease. In some cases, HCM may be detected incidentally during a routine veterinary examination or diagnostic testing for unrelated issues.

​

Diagnosis:

Diagnosing HCM typically involves a combination of physical examination, auscultation (listening to the heart with a stethoscope), imaging studies such as echocardiography (ultrasound of the heart), and possibly electrocardiography (ECG) to evaluate the heart's electrical activity.

​

Treatment:

Treatment for HCM aims to manage symptoms, prevent complications, and improve the cat's quality of life. Depending on the severity of the condition and the presence of complications, treatment may include:

1. Medications to manage symptoms such as diuretics (to reduce fluid buildup), beta-blockers (to regulate heart rate), and ACE inhibitors (to reduce blood pressure) as well as antiplatelet or anticoagulant medications to reduce the risk of blood clots.

2. Dietary management to maintain optimal body condition and reduce stress on the heart.

3. Regular monitoring by a veterinarian to assess the cat's condition and adjust treatment as needed.

4. Surgical procedures or cardiac catheterization may be recommended for severely affected cats, but these options are less common and carry higher risks.

​

Prognosis:

The prognosis for cats with HCM varies depending on the severity of the condition, the presence of complications, and the response to treatment. Some cats may live relatively normal lives with appropriate management, while others may experience progressive deterioration of heart function and complications such as heart failure or sudden death. Early detection, regular veterinary care, and diligent management are key to optimizing the prognosis for cats with HCM.

​

Is there genetic screening?

No. HCM can arise from a range of genetic mutations, while being influenced by epigenetic and environmental factors such as obesity and diet. Currently, only four mutations in cats have been identified, with genetic tests validated solely for determining causation in Maine Coons and Ragdolls.

​

What can breeders do?

The ​Siberian Cats Health Association offers the following guidance:

"Because of the complex nature of the disease and the pervasive nature of HCM in cats it is unlikely HCM will ever be eliminated.  As breeders, we can only do our best to keep track of the health of our kittens, cardiac screen our breeding cats even after they’ve been retired, and use predictive tools like DNA if/when they become available.  Even doing all of that and eliminating affected cats from breeding and their close relatives it is still possible to have HCM in a breeding program.  The best way to help the breed is to be open about testing results whether good or bad, and incidences of HCM.  This is really the only way to reduce the effects within the breed."

​

What can pet owners do?

Recognizing that HCM can have an epigenetic basis, it is vital that we, as cat owners, maintain our cats at a healthy weight. Obesity can increase the expression of heart problems. The other most important thing you can do is to educate yourself about HCM.

​

Want to learn more about HCM in felines?

Below are a few articles and resources you may find helpful. If you have found a helpful article or other resource and feel it should be shared here, please don't hesitate to email me!

​

General Articles

​

Heart disease in cats (Hypertrophic Cardiomyopathy)

Washington State University College of Veterinary Medicine

Feline hypertrophic cardiomyopathy (HCM) thickens the heart muscle and is common in cats. Signs vary from none to lethargy, labored breathing, weakness, or sudden death. Diagnosis involves exams and tests like X-rays and echocardiograms. Treatment includes medications. Regular check-ups are crucial, and if symptoms occur, contact a veterinarian or specialized facility for tailored treatment.

​

The Feline Cardiomyopathies: 1. General concepts

Mark D Kittleson & Etienne Côté

Journal of Feline Medicine and Surgery • Published October 25, 2021

Feline cardiomyopathies are common heart diseases in adult domestic cats. Hypertrophic cardiomyopathy (HCM) is the most prevalent form. Clinically, they're often similar, making diagnosis challenging. Cats may show no symptoms or exhibit signs like heart murmurs, dyspnea, or sudden death. Treatment typically doesn't alter disease progression, and management remains similar regardless of the type. Accurate diagnosis is crucial for prognosis.

​

The Feline Cardiomyopathies: 2. Hypertrophic cardiomyopathy

Mark D Kittleson & Etienne Côté

Journal of Feline Medicine and Surgery • Published November 23, 2021

HCM's genetic cause is known in some breeds, but not most. SAM often causes heart murmurs in HCM, and while severe cases need treatment, milder ones may not. The distinction between HCM types isn't crucial in cats. Diastolic dysfunction primarily causes clinical signs and death, leading to heart failure and ATE. Treatment aims to control heart failure and prevent complications with antithrombotic drugs.

​

​

Articles Focused on Other Breeds

​

Cardiac troponin I in healthy Norwegian Forest Cat, Birman and domestic shorthair cats, and in cats with hypertrophic cardiomyopathy

Sofia Hanås, Anders Larsson, Jesper Rydén, Inger Lilliehöök, Jens Häggström, Anna Tidholm, Katja Höglund, Ingrid Ljungvall, & Bodil S Holst

Journal of Feline Medicine and Surgery • Published September 8, 2022

In healthy cats, Birman cats and neutered male cats had higher levels of cTnI compared to Norwegian Forest cats and intact females, respectively. cTnI levels were also linked to heart rate. In cats with HCM, cTnI levels were associated with thicker left ventricular walls and a higher left atrial-to-aortic root ratio. Cats with HCM had higher cTnI levels than healthy cats, and those with HCM and left atrial enlargement (LAE) had higher levels than those without LAE.

​

Body size and metabolic differences in Maine Coon cats with and without hypertrophic cardiomyopathy

Lisa M Freeman, John E Rush, Kathryn M Meurs, Barret J Bulmer, & Suzanne M Cunningham

Journal of Feline Medicine and Surgery • Published September 21, 2012

This study aimed to understand the relationship between growth, glucose regulation, and hypertrophic cardiomyopathy (HCM) in Maine Coon cats. Measurements and tests were conducted on cats over two years old, including body measurements, echocardiography, blood tests for insulin and IGF-1, and DNA testing. Results showed that cats with HCM were older, heavier, and more obese compared to those without HCM. They also had higher glucose and IGF-1 levels and were from smaller litters. The study suggests that early growth, nutrition, and obesity may influence the development of HCM in genetically predisposed cats.

​

​

Other Resources

​

Siberian Cat Health Association

The Siberian Cat Health Association (SCHA) comprises dedicated breeders committed to preserving the Siberian Cat's health. The SCHA advocates for transparency to facilitate informed breeding choices.

​

​

​