What is Hypertrophic Cardiomyopathy in Cats?

What is Hypertrophic Cardiomyopathy in Cats?

What is it?

Hypertrophic Cardiomyopathy (HCM) is a common heart disease in cats, characterized by the thickening of the heart muscle. HCM can cause various symptoms and health problems and may ultimately lead to heart failure or sudden death. HCM can be challenging to diagnose and manage and requires ongoing care and monitoring by a veterinarian.

How is it Treated?

Treating Hypertrophic Cardiomyopathy in cats typically involves medications to manage the symptoms and reduce the risk of complications such as heart failure and blood clots. Medications may include beta-blockers, calcium channel blockers, and anticoagulants. In some cases, surgical or interventional procedures may be necessary to alleviate symptoms or correct structural abnormalities in the heart. 

Breed Predispositions

Maine Coon Ragdoll American Shorthair Persian Sphynx British Shorthair Scottish Fold Norwegian Forest Cat Bengal Siamese


When Karen brought home her fluffy Maine Coon, Simba, she never imagined that a routine check-up at the vet would reveal a concerning diagnosis. After noticing Simba’s increased breathing rate and lethargy, she discovered that her beloved feline companion was suffering from hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy in cats, often called HCM, is characterized by an abnormal thickening of the heart’s walls, leading to insufficient blood supply throughout its chambers. It is caused by a genetic defect that causes the muscle of the ventricles, or lower chambers of the heart, to become enlarged and unable to contract normally. As this occurs, it results in an inability for proper circulation throughout the body. If not addressed properly and promptly, this can lead to difficulty breathing, fatigue, and other adverse medical consequences for your cat.

The most common form of cardiomyopathy in dogs is dilated cardiomyopathy (DCM). DCM causes enlargement of the left ventricle, which pumps oxygen-rich blood throughout the body. This condition usually occurs when a cat is between two and six years old.

Hypertrophic cardiomyopathy is another form. This is rare in cats, but some cases have been reported. HCM affects the thickening of the heart’s walls, causing them to enlarge. As a result, the heart becomes stiff and cannot pump efficiently. Cats with this condition often experience exercise intolerance, sudden death, congestive heart failure, and syncope (fainting).

Types of Hypertrophic Cardiomyopathy in Cats

Hypertrophic cardiomyopathy is a genetic condition that damages the heart muscle. HCM causes the thickening of the left ventricle’s walls (the heart’s main pumping chamber). In some cases, the right ventricle enlarges as well. As a result, the heart pumps less blood throughout the body. This thickening makes the heart pump inefficiently and may lead to congestive heart failure.

There are two types of HCM in cats: Hypertrophic obstructive cardiomyopathy (HOCM) and non-obstructive hypertrophic cardiomyopathic (NOHCM). Both affect older cats, especially males.

HCM is most common in Maine Coon cats, Persians, Siamese, Himalayans, and Abyssinians. NOHCM is rarer than HOCM and occurs mainly in domestic shorthairs.

Types of Hypertrophic Cardiomyopathy in Cats

Both forms of HCM may be inherited. Some cases occur spontaneously.

What Causes Feline Hypertrophic Cardiomyopathy?

There are a variety of factors that can contribute to the development of this infectious disease in cats. Some possible causes include genetics, infection (such as feline leukemia virus), dietary problems (e.g., feeding high-fat diets), and environmental toxins.


Hypertrophic cardiomyopathy (HCM) is a genetic disease that causes the thickening of the heart muscle. HCM affects dogs and cats, although it is most common in large-breed dogs. The condition may be inherited or occur spontaneously.

Genetic testing is available for some breeds, including Doberman Pinschers, Golden Retrievers, Labrador Retrievers, Rottweilers, Boxers, German Shepherds, Great Danes, Saint Bernards, and Siberian Huskies. Unfortunately, genetic testing is not currently available for cats.


Feline leukemia virus (FeLV), a retrovirus that infects domestic cats, is known to cause HCM in cats. FeLV is spread through saliva and blood, and infected cats often develop enlarged lymph nodes, fever, and lethargy.

 Dietary Problems

Diet plays a huge role in managing heart disease. Therefore, a cat’s diet suffering from hypertrophic cardiomyopathies (HCM) should be carefully monitored.

Many cats with HCM often develop kidney problems due to dietary imbalances. They may also suffer from gastrointestinal issues because of poor digestion and absorption.

Environmental Toxins

Environmental toxins are chemicals in our air, water, soil, food, and household items that may cause health problems. They include lead, mercury, arsenic, pesticides, herbicides, PCBs (polychlorinated biphenyls), dioxins, and polybrominated diphenyl ethers (PBDEs).

How Do I Know if My Cat has Hypertrophic Cardiomyopathy?

HCM occurs most often in young adult cats, although it may occur at any age. The condition usually causes no symptoms until the cat reaches adulthood.

If your cat shows signs of weakness, lethargy, coughing, breathing difficulties, vomiting, diarrhea, or sudden weight loss, his veterinarian should immediately see him. Your vet will perform a physical exam and listen to your cat’s heartbeat through a stethoscope. Then, he may recommend additional tests, including echocardiography and cardiac ultrasound.

Diagnosis of HCM in Cats

Diagnosis of HCM in cats

To diagnose HCM, veterinarians perform a thorough physical examination, including checking the cat’s gait, pulse rate, temperature, and respiratory rate. 

Vets use echocardiography to detect HCM in cats. Echocardiography uses sound waves to create images of the cat’s heart. The vet looks at these images to determine whether there are any abnormalities. They may also use ultrasound imaging to determine whether there is an obstruction in the mitral valve.

An electrocardiogram (ECG) measures electrical activity in the heart. An ECG records nature muscle cells’ electrical signals during each heartbeat. The ECG traces show where the heartbeats occur and when they begin and end.

An ECG is used to diagnose problems with the heart rhythm, including arrhythmias (irregular heartbeat), conduction abnormalities (problems with the electrical pathways through which impulses travel within the heart), and structural defects (abnormalities in the structure of the heart).

Serum biomarkers are elevated in patients with HCM compared to healthy individuals. These biomarkers include brain natriuretic peptide (BNP), troponin I, and creatine kinase MB fraction (CKMB).

Blood samples are taken to test for abnormalities in electrolytes and hormones.

Treatment and Management

Your vet may suggest treatment options based on whether your cat has been diagnosed with obstructive or non-obstructive HCM. Treatment depends on the severity of the disease and its effects on your cat’s quality of life. Some cats live long lives with HCM; others die suddenly due to complications associated with the disease.

Although there is currently no cure for HCM, many treatments exist to help control the progression of the disease and improve your cat’s overall health. These include medications, dietary supplements, and surgery.

  • Medications used to treat HCM include beta-blockers, calcium channel blockers, diuretics, nitrates, digoxin, and angiotensin receptor antagonists. Beta-blockers slow down the rate at which the heart beats, reducing the workload on the heart and improving exercise tolerance. Calcium channel blockers relax the heart muscles and reduce the force of contraction.

Diuretics remove fluid from the body and decrease the work required by the heart. Nitrates dilate the arteries and lower blood pressure. Digoxin slows the heart rate and reduces contractions. Angiotensin receptor antagonists block the action of the hormone angiotensin II, which constricts blood vessels and increases blood pressure.

  • Dietary supplements used to treat HCM are available over the counter. They include omega-3 fatty acids, antioxidants, vitamins, minerals, and herbal extracts. Omega-3 fatty acids are essential nutrients found in fish oil.

Antioxidants protect cells against damage caused by free radicals. Vitamins and minerals support healthy cell function and growth. Herbal extracts contain compounds that may benefit the cardiovascular system.

  • Surgery is sometimes recommended when medical management fails to control the disease. Surgical procedures to relieve obstruction in the left ventricular chamber include septal reduction, mitral valve repair, tricuspid annuloplasty, and mitral valve replacement.

In some cases, surgical intervention is not possible or advisable. Instead, medication may be prescribed to control the disease and improve your pet’s quality of life.

Frequently Asked Questions

The average life expectancy of cats with HCM is ten years. However, some cats survive longer than this. A study published in the Journal of Feline Medicine & Surgery found that 50% of cats with HCM lived at least 15 years.

The cause of HHC is unknown. However, some breeds seem predisposed to developing this condition. For example, the American Pitbull Terrier, English Springer Spaniel, Irish Setter, Labrador Retriever, Old English Sheepdog, Pug, Rhodesian Ridgeback, Shih Tzu, Standard Schnauzer, Toy Fox Terrier, Yorkshire Terrier, and Wirehaired Vizsla have been reported to develop HHC.

Cats with mild symptoms often show no signs of illness until adulthood. They usually do not suffer skeletal deformities, although some may develop joint laxity. However, some cats may have difficulty walking because their joints become loose and painful. Other cats may have trouble standing up or jumping. Some cats may have breathing difficulties due to chest wall abnormalities. 

A Hypertrophic Cardiomyopathy Test for Cats costs $100-USD 150. It is typically used to diagnose hypertrophic cardiomyopathy in cats. It can also monitor a cat’s progress with this condition.

This is difficult to answer as there is no standardized test for heart disease in cats, and the speed of progression may vary significantly from one cat to another. For example, some cats with hypertrophic cardiomyopathy may initially show little or no signs of the condition. In contrast, others may develop significant difficulty breathing and heart failure quickly.

The final stages of CHF in cats are when the cat’s body cannot pump enough blood through its circulatory system. This causes fluid buildup in the lungs and abdomen, which leads to breathing problems. The kidneys become damaged, causing them to stop working correctly. In some cases, the liver stops functioning. If the condition continues untreated, the cat will die.

This is a tough decision. There are many factors involved. We should first consider whether the cat has any quality of life left. If they do, we must weigh their quality of life against the suffering they would endure from the procedure.

If the cat’s quality of life is poor, euthanasia is appropriate. However, if the cat’s quality of life is good, we must decide whether the cat can recover from the procedure. If so, we must weigh the procedure’s benefits against its risks.

Several different heart medications may help manage the condition. Some common medicines used to treat hypertension and other cardiovascular diseases include angiotensin-converting enzyme inhibitors (ACE inhibitors), beta-blockers, calcium channel blockers, and statins. Depending on the severity of the cat’s hypertrophic cardiomyopathy, treatment may include a combination of these drugs or another therapy specifically designed for this condition.

Hypertrophic cardiomyopathy is a disease in the heart muscle that causes an enlarged and thickened heart. The condition can be inherited, but it can also develop due to other factors (such as exposure to toxins or drugs). If untreated, hypertrophic cardiomyopathy may lead to congestive heart failure and death. 

If your cat has hypertrophic cardiomyopathy, it is essential to take her to a veterinarian for assessment and treatment as soon as possible. If your cat isn’t showing any other signs of illness, you may only need to give her a prescription diet and glucosamine supplements. However, if your cat has difficulty breathing or other symptoms suggest her heart health is deteriorating, she will require treatment with medications and surgery.

The prognosis for cats with hypertrophic cardiomyopathy depends on the severity of the condition and whether they receive proper care from their veterinarian. However, if left untreated, most cats will eventually develop heart failure or death.

Most cats do not experience pain with hypertrophic cardiomyopathy. Some may experience mild discomfort at rest or when active, but cats do not typically experience significant pain in hypertrophic cardiomyopathy. However, if your cat experiences increased heart rate or shortness of breath, this may be a sign that the condition is worsening and should be evaluated by a veterinarian.

Although there is no cure for hypertrophic cardiomyopathy in cats, there is good news. The disease’s prognosis depends on several factors, including the severity of the condition at diagnosis and the individual cat’s overall health. However, most cats with hypertrophic cardiomyopathy will live long and healthy lives if treated early and aggressively.

There is no consensus on the life expectancy of cats with hypertrophic cardiomyopathy. Some studies report shorter life spans, while others report equivalent or longer-lived cats.

Some cats may develop hypertrophic cardiomyopathy (HCM) because of their genetics. In contrast, others may experience the disease after developing another medical condition, such as heartworm infection or systemic lupus erythematosus. Unfortunately, there is no cure for HCM in cats; treatment typically focuses on managing the symptoms.

Some cats are more prone to developing hypertrophic cardiomyopathy than others, such as Persians and Siamese., such as Persians and Siamese, are more prone to developing hypertrophic cardiomyopathy than others. The condition is caused by the growth of heart muscle cells beyond their average size and can lead to chest pain, shortness of breath and death if not treated. Affected cats may also have signs such as irregular heartbeat or weight loss that might indicate the disease is progressing.

Cats with cardiomyopathy are generally recommended to eat more protein and less fat. Diet modifications may include increasing the number of high-quality proteins in their food, choosing cat-safe meats, and including low-fat or nonfat sources of milk and gravy.

There is no one-size-fits-all answer to this question, as the rechecks and monitoring recommendations will vary depending on each cat’s case’s specific facts and circumstances. However, some recommended rechecks and monitoring procedures for cats with HCM include: Regular ultrasound screenings to check for heart murmurs

  • Urinalysis (to determine if there are signs of renal failure); (to determine if there are signs of renal failure); Anemia testing
  • Radiographic imaging studies such as an echocardiogram or magnetic resonance imaging (MRI) scan detect any significant changes in the cat’s heart structure or function.

Screening tests for HCM include an echocardiogram and a cardiac MRI. An echocardiogram tests the heart’s size, shape, and function. A cardiac MRI does the same thing as an echocardiogram but uses magnetic resonance imaging to see inside the heart’s chambers.

Disclaimer: The information provided on this veterinary website is intended for general educational purposes only and should not be considered as a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a licensed veterinarian for any concerns or questions regarding the health and well-being of your pet. This website does not claim to cover every possible situation or provide exhaustive knowledge on the subjects presented. The owners and contributors of this website are not responsible for any harm or loss that may result from the use or misuse of the information provided herein.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *