Heart failure in cats is scary—pet parents don’t often notice symptoms until it’s an emergency, and it can be deadly. Up to 15 percent of the cat population is affected with heart disease which can lead to heart failure. 

The following is a comprehensive look at this condition in cats.

What is Heart Failure?

Heart failure is when the heart can no longer fill and pump blood to the rest of the body well enough. Without emergency treatment, it is deadly. 

Heart disease in cats can lead to heart failure if not managed, or if the disease gets worse over time. Heart disease consists of a variety of issues that affect how well the heart functions, but they do not require emergency treatment.

There are two types of heart failure in cats. One is heart failure as described above. The other is congestive heart failure. Congestive heart failure occurs not only when the heart has failed, but the lungs begin to fill with fluid.

Symptoms of Heart Failure in Cats

Cats are very good at hiding symptoms of illness, and that is no different in cases of heart failure. Because of this, many pet parents do not notice the earlier signs of heart failure until their cat is in an emergency situation. 

Early symptoms of heart failure in cats may include a decrease in appetite, being less active or hiding more than usual. 

With heart failure, subtle and specific symptoms include:

• Exaggerated breaths when looking at the chest or belly (which may not be constant)
• Need to take breaks or a fast breathing rate after exercise and play (exercise intolerance)
• Not as active (lethargy)

Congestive heart failure has more obvious symptoms, because the lungs are filling with fluid which makes it difficult for a cat to breathe. Usually pet parents notice symptoms once heart failure has progressed to being congestive. 

Symptoms may include:

• Complete inactivity
• Fast breathing rate (constant, but worse with stress or movement)
• Increased abdominal effort (visible movement of the belly with each breath)
• Laying with chest on the ground and the head up
• Open-mouth breathing or panting
• No appetite
• Enlarged belly
• Cough (rare)

What Causes Heart Failure in Cats?

Heart failure can be caused by a variety of conditions. These conditions generally fall into three categories:

Cardiomyopathy. The muscle that makes up the heart, responsible for pumping blood out of the heart, is diseased.

Valvular disease. The valves found inside the heart that control the flow of blood into and out of the heart are diseased.

Vascular disease. The major blood vessels leaving or going to the heart are diseased. This type is related to changes in blood pressure.

The majority of conditions that eventually lead to heart failure are either caused by genetics (inherited from the cat’s parents) or the cause is unknown. 

Keep in mind many heart conditions do not often lead to heart failure, such as valve dysplasia. Valve dysplasia means a cat was born with an unusually shaped valve, and the majority of these cats live full lives with no evidence of heart disease.

There are several breeds of cats that are more often affected by heart disease because of their genetics. These include:

• Maine Coon*
• Ragdoll*
• Birman
• British Shorthair
• Norwegian Forest Cats
• Siamese
• Sphynx

*These two breeds are more commonly recognized as being affected by heart disease, supported by several studies on genetics. (1) (2)

Diagnosing Heart Failure in Cats

Diagnosing heart failure must include imaging including X-rays or ultrasounds. However, in an emergency situation, a cat who is struggling to breathe cannot go through imaging right away as any additional stress could be deadly. Many times veterinarians have to work carefully with your cat and initially make an assumption that your cat has heart failure based on a physical examination alone. 

Your veterinarian will perform blood tests. Basic bloodwork is important to rule out other possible causes of your cat’s symptoms and to recommend safe medications. There are two specific blood tests for the heart: 

• Cardiac Troponin 
• ProBNP

Both of these may be used to look for evidence of heart disease, but they cannot diagnose heart failure with certainty.

Two other important and common tests are monitoring your cat’s blood pressure and conducting an electrocardiogram (EKG or ECG). This test involves placing small clips on your cat’s skin in various places to measure electrical signals that go through the heart. It is used to evaluate the rhythm of the heart, which may need to be treated if abnormal.

Once your cat is stable, imaging will be performed to evaluate the heart. There are two main types of imaging, including:

• X-rays (also known as radiographs). Veterinarians can see the size of the heart and condition of the lungs. X-rays are not very specific to identifying heart disease.
• Ultrasound. Veterinarians can look very closely at the heart and lungs. Echocardiogram is an ultrasound performed by a heart specialist (cardiologist) to look for specific heart disease. 

Treatment for Heart Failure in Cats

Heart failure is not a curable disease. While heart failure itself can be resolved in some cases, underlying heart disease cannot be cured and may cause the heart to fail again in the future. 

Oftentimes, heart failure is manageable. For cats that have fluid in the chest or in the belly, fluid removal will be performed to allow your cat to breathe easier. If fluid is removed from the chest, it is called thoracocentesis. If fluid is removed from the belly, it is called abdominocentesis. Some cats will require a few of these procedures and other cats may only undergo one procedure. 

Your veterinarian will likely give a pain medication to your cat beforehand, but it is no more painful than a small injection at the doctor’s office. 

After a cat has been diagnosed with heart failure, medications will be prescribed to improve the heart’s ability to fill and pump blood to the rest of the body. Each cat’s response to medication is different, and there are many types of heart disease possible. Therapy may not be the same between two cats. 

Diet should be discussed with your veterinarian if your cat is experiencing heart failure and an underlying heart disease. Ensuring your pet’s diet has an appropriate level of salt (sodium) and taurine (essential amino acid needed in cat’s diets), as well as additional supplements such as omega-3 fatty acids is important to your pet’s heart health.

Prognosis for Heart Failure in Cats

Prognosis varies widely depending on what type of heart disease your cat has, how severe the heart’s condition is, and if other conditions occurred with heart failure such as thromboembolism. 

The life expectancy for cats in heart failure ranges from 3 to 18 months after diagnosis.

Medications Used to Manage Heart Failure in Cats

Common medications used to manage heart failure in cats include:

• Diuretics, such as furosemide. These medications drain the extra fluid that is filling the chest.
• Pimobendan. This medication affects the heart muscle, allowing it to fill the heart with more blood and pump more effectively. (Use of pimobendan in cats is considered “off-label” usage by the FDA.)
• ACE-inhibitors, such as benazepril. These medications cause blood vessels to dilate so more blood can pump out of the heart, and blood pressure is lowered.
• Antithrombotics, such as clopidogrel. These medications prevent clots from being formed in the heart, which can leave the heart and clog important vessels elsewhere in the body.
• Antiarrhythmics, such as diltiazem. If your cat has a heart rhythm issue, one of these medications may be prescribed to correct it.

Pimobendan, furosemide, clopidogrel, and benazepril are available as FDA approved drugs, and, when appropriate for your cat as determined by your veterinarian, compounded forms. If you have trouble giving your cat a tablet, some of these medications may be available in alternate dose forms, such as an oral liquid, that can be made by a compounding pharmacy for easier administration.

General Cost to Treat Heart Failure in Cats

Heart failure requires emergency care, a hospital stay for a minimum of 24 hours, tests, and medications. If your cat is diagnosed with heart failure, you should expect to spend more than $1,000. 

This is highly variable depending on where you live and how severe your cat’s condition is. The cost is higher if your cat visits the cardiologist to have the specific heart disease (the specific cause of heart failure) diagnosed.

The cost of medication to maintain, treat or prevent heart failure is approximately $20+ per month.

How to Prevent Heart Failure in Cats

The only prevention for heart failure is to work with your veterinarian on identifying heart disease before it becomes heart failure. Unfortunately, there are no symptoms associated with heart disease itself that pet parents would recognize. 

If your veterinarian identifies a heart murmur during routine physical examination, it may not indicate significant heart disease but tests need to be performed to determine the cause of the heart murmur. 

Keep in mind that a lack of a heart murmur does not indicate a lack of heart disease. If your cat is a breed known for developing heart disease, speak with your veterinarian about having your cat tested. 

Related Conditions 

• Cardiomyopathy (typically hypertrophic)
• Aortic Thromboembolism (ATE)
• Renal Disease in Cats
• Feline asthma (bronchitis)
• Arrhythmia in Cats
• Hypotension in Cats
• Hypertension in Cats

Covetrus encourages the use of an FDA approved product whenever possible, within a valid veterinary-client-patient relationship (VCPR). However, we realize that in order to achieve a desired therapeutic outcome, a customized compounded preparation may be necessary. Covetrus compounding pharmacies, a fully PCAB accredited pharmacy with compliance to USP 795/797/800 standards along with a registered cGMP 503B outsourcing facility means you can be confident in the quality of every medication order.