Canine CareHealth

What Causes Congestive Heart Failure in Dogs? Everything You Need to Know

Congestive heart failure (CHF) happens when your dog’s heart can’t pump enough blood. This can lead to life-threatening complications, which is why it has to be addressed right away. Knowing what causes congestive heart failure in dogs is the start together with other proactive approaches.

Since it involves one of the most sensitive body organs of your pet, it’s essential to consult with a veterinarian. In this post, we will discuss what causes congestive heart failure in dogs, its symptoms, and what you can do about it.

Understanding congestive heart failure in dogs

Congestive heart failure (CHF) causes the heart to lose its ability to pump enough blood for the body. When this happens, the blood will flow back to the lungs. This will cause body fluids to accumulate in various body cavities which will strain the heart and lungs even more.

Take note that CHF never goes away on its own. As time passes by, the condition worsens, which can lead to the dog’s death.

CHF isn’t a disease itself, but a secondary phenomenon due to advanced heart disease. Over time, the lungs will be filled with fluids, making it difficult for the dog to breathe. Further physical exertion may worsen the discomfort and pain that your pet is experiencing.

In this video, Dr. Christian Broadhurst tells us more about congestive heart failure in dogs:

Right-sided CHF vs. left-sided CHF

There are two types of CHF: right-side and left-sided. The following are the differences between the two:

**Right-sided congestive heart failure (RS-CHF)

This isn’t the most common type to happen among dogs, but it can still put a pet’s life in danger. An RS-CHF occurs when the blood returns to the heart. When the heart pumps, the blood is pushed back to the right atrium through the tricuspid valve. In a healthy heart, the pumped blood should exit the lungs after oxygenation. For dogs with RS-CHF, the blood doesn’t even enter the lungs.

Over time, fluids will accumulate in the abdomen and cause peripheral edema on the limbs.

**Left-sided congestive heart failure (LS-CHF)

Meanwhile, LS-CHF happens when the blood from the left ventricle leaks back to the left atrium and into the lungs. For normal dog hearts, the left ventricle should push the pumped blood through the systemic circulation.

When this happens, the fluids will seep through the lung tissues. This will lead to pulmonary edema and difficulty of breathing.

LS-CHF is the most common among dogs. The symptoms are easy to spot, but many pet owners tend to dismiss it as a minor problem. Below, we discussed the symptoms in detail to help you diagnose the problem on your dog.

Take note that both right-side and left-sided CHF are life-threatening. Immediate treatment is imperative to prevent further complications on your dog’s health. 

What causes congestive heart failure in dogs?

Many conditions can cause congestive heart failure. Still, the following are the most common, especially for active canines.

-Congenital defects

Congenital defects are the most common culprit behind CHF. The dog could have a defective heart, a blocked vein, and other internal deformities that cause the blood to flow back into the heart and lungs.

Most congenital defects in the heart require an intensive surgical operation to correct. And since your doggo will be born with it, early diagnosis is crucial. As your dog grows and ages, the strain on its heart becomes more dangerous.

-Breed-related predispositions

It’s said that small breeds are more likely to develop or be born with conditions that will lead to congestive heart failure. This is because heart valves of small dogs degenerate faster than larger canines. Still, this isn’t absolute as large doggos can be prone to CHF as well.

-Weakened heart

Even if your dog has been born healthy and its breed isn’t known to have major heart problems, it can still develop CHF. The weakening of the heart can lead to this condition. Like humans, a dog’s heart may weaken due to obesity, heart diseases, infection, parasites, and other conditions.

-Heart valve disease

Most cases of CHF among dogs are due to a specific heart valve disease. The most common is MVI or Mitral Valve Insufficiency. This condition is associated with a heart murmur and will usually occur when the mitral valve wears out.

As the valve weakens, it will start to leak fluids. MVI itself can be caused by various conditions including a ruptured chordae tendinae. In this case, CHF becomes a complication or a tertiary condition from other heart problems.

-Old age

As your dog ages, it becomes susceptible to various health problems, including CHF. If your pooch’s breed has a predisposition to this condition, they will have a higher risk of developing it upon reaching the senior age.

Moreover, old dogs tend to have worn out heart valves which expose them to the risk of mitral valve insufficiency. If not treated right away, it will lead to congestive heart failure.

-Unhealthy lifestyle

Dogs with poor diets, improper activities, and bad hygiene have a higher risk of developing CHF later in life. Some will even develop this condition in their early years. As the pet owner, it’s your responsibility to keep your doggo healthy and safe all the time.

In addition, regular visits to the vet should prevent any heart problems and complications. Being watchful also pays off, especially if your dog is starting to become lethargic and highly irritated.

what causes congestive heart failure in dogs

Tell-tale signs of CHF

Congestive heart failure always shows apparent symptoms. However, some of it could be mistaken to be a simple irritation that could die down on its own. But for your pet’s sake, make sure that you keep the following signs in mind. If you observe any of these, it’s best to schedule a trip to the vet’s clinic.

**Intense coughing

Dogs that cough, especially after exercising, more than usual,  are likely experiencing the onset of CHF. The coughing happens since fluids build up on the lungs. This makes breathing difficult and physical exertion will worsen it, leading to incessant coughing.

Some canines with advance CHF will cough even while sleeping.

**Difficulty to breathe

Is your dog panting for no reason? It’s best to have it checked for CHF. Again, the difficulty to breathe has something to do with the backflow of blood to the lungs. Also, as fluids build up in different cavities in your pet’s chest, it will put pressure on the heart and lungs.

**Getting tired easily

If your active dog suddenly becomes reluctant to exercise or is getting tired easily, you have to get it checked by a vet. Tiring is associated with the difficulty of breathing. Dogs with CHF will also have bluish or pale gums, especially after physical exertion. It’s due to the lack of blood flow in the gum area.

**Swollen belly and limbs

Edema will set in once the heart can’t circulate blood and fluids properly. This will lead to the fluids accumulating in different parts of the body (also known as edema). From the outside, it will appear that your dog has a bloated belly and swollen limbs.

Just like with humans, try pressing the swollen parts gently. If the pressed surface didn’t come back to normal, your dog is experiencing edema. This has to be treated right away as edema is a serious lymphatic and circulatory problem. If not, your dog’s life will be compromised.

**Weight loss

As the CHF condition worsens, the dog will start to lose weight. This is due to the inability of the body to store fats. Also, it has something to do with muscle wasting as an effect of CHF on the body.

The discomfort of congestive heart disease will also lead to poor appetite, difficulty in exercising, and complete inactivity. All of these will impact the health and weight of your dog.

Other symptoms of CHF include fainting when the blood flow to the brain gets blocked. Other dogs will experience increased respiratory rate due to the poor blood circulation and accumulation of fluids in the wrong areas of the body.

Can CHF cause heart attacks in dogs?

Heart attacks aren’t common in canines, but it can happen in some cases.

In humans, a heart attack is caused by the deaths of cells due to poor oxygenation or lack of oxygen itself. The poor oxygen supply is linked to blocked vessels and veins. This process is referred to as myocardial infarction.

A heart attack due to myocardial infarction isn’t typical among dogs. Some canines may experience heart attacks, but it’s usually due to lingering heart disease.

How is CHF in dogs diagnosed?

Be it in canines or humans, heart problems are diagnosed through a series of tests. This is to ensure that the symptoms are indeed pointing to CHF.

The following are some of the tests that you should expect for the veterinarian to perform:

**Listening to the heart using a stethoscope

Upon arriving in the vet’s clinic, the first thing that the animal doctor would do is a physical inspection. Also known as auscultation, listening to the heart using a stethoscope will help determine if the dog has a heart murmur.

A heart murmur is the sound that turbulent blood flow makes inside the heart. A normal heart will usually have two sounds (lubb-dubb). However, a dog with a heart murmur will have a whooshing sound. Nevertheless, not all cases of heart murmur are serious, but it can be a sign that your pooch has problematic blood flow.

Aside from the heart, the vet will also use the stethoscope to listen to your dog’s lungs. Any abnormal sound will require further assessments.


This is done to check the pumping efficiency of your dog’s heart. Ultrasound waves will be used here to check the thickness of the heart’s chambers, ventricles, and atriums. Also, the vet will look into the heart contraction to see if it’s normal for your dog’s size and age.


If the vet needs further analysis of your pet’s heart, he or she will perform an electrocardiogram. This uses an electrical charge to check the dog’s heart rate and rhythm. Since CHF causes abnormal rhythms, an electrocardiogram is an integral test to identify which side of the heart is causing congestive heart failure.


Also, the veterinarian will subject your dog for chest X-rays to see if the size of the heart is normal. Also, it’s the best tool to see if fluids are building up on the animal’s lungs and surrounding cavities. Usually, the result of the X-ray test will confirm the occurrence of CHF.

**Blood tests

This isn’t usually done when diagnosing CHF, but some vets will recommend it. This is when your dog has been experiencing CHF for a long time. Due to poor circulation, your canine’s kidney and liver function might also be compromised.

Take note that all these tests will take more than one day to finish. In some cases, the vet may need to confine your pet in the clinic for observation and initial treatment.

How CHF in dogs is treated

Once the vet identified what causes congestive heart failure in dogs, he or she will now plan out a treatment procedure.  Take note that the treatment for CHF will vary depending on what’s causing it. Also, there’s no specific cure for congestive heart failure right now. All that you and the vet can do is to cure the possible condition that’s causing CHF. Other than that, only medications and treatments to ease the symptoms can be used.

Nevertheless, the following are some of the potential treatments for various CHF conditions:


If your dog’s congestive heart failure is due to a congenital defect, torn valve, or malfunctioning pacemaker, a surgical procedure is needed.

**Low-salt diet

A low-salt diet will help reduce fluid buildup on your dog’s body. This will be paired with other treatments to address the backflow of the blood.

**Reduced activity

Since your dog will experience the difficulty of breathing and poor circulation, the veterinarian will recommend a reduction in the doggos’ activity. This is while the treatment is ongoing as well as to prevent further complications.


Veterinarians will administer various medications to improve the fluid flow in your dog’s body. If the cause of the blood backflow is a blockage, vets may recommend a specific medication to melt it. Most of the time, vets will administer diuretics to a canine with CHF and edema. This is to drain the fluid that built up in different parts of the canine’s body.

**Oxygen therapy

For dogs that are struggling to breathe, vets will perform oxygen therapy until your doggo can breathe on its own. Usually, oxygen therapy requires hospitalization or confinement in the vet clinic. While this treatment is ongoing, other medications will be given to your pooch to improve its condition.

NOTE: Never self-medicate a dog with congestive heart failure. Proper diagnosis and professional treatment are the only things that will help your dog. In the long run, home remedies will do more harm than good.

In this video, Dr. Lera of Heron Lakes Animal Hospital tells us how vet clinics deal with CHF in dogs:

Will your dog recover fully?

Since there’s no cure to congestive heart failure among dogs, vets can only help prolong your pet’s life. Also, they can make your pet more comfortable so it can live its life to the fullest. After a series of medication, your pooch can regain its strength. Still, you’ll have to deal with life-long care.

Also, dogs with CHF can no longer perform rigorous physical activities or anything that will put too much strain on their heart.

Early diagnosis is crucial…

Remember that the sooner your dog gets diagnosed, the higher the chance that it will restore its health. The pooch may not recover fully, but the early diagnosis will prevent complications and other conditions that may branch out of congestive heart failure. Knowing what causes congestive heart failure in dogs is crucial in saving your dog’s life.

Also, you should always consult a veterinarian if once you observe symptoms of CHF on your dog. Early and proper diagnosis has saved the lives of many canines, regardless of condition.

The cost of congestive heart failure treatment

CHF comes with a hefty price, both in your dog’s health and in your pocket. In fact, echocardiogram tests can be as steep as $500 to $600. On the other hand, treatments for heart murmur can be as expensive as $20,000 in the worst cases.

While treatments for congestive heart failure varies, it will likely fall anywhere between $500 to several thousand. Take note that CHF can be a secondary condition only, so you have to consider the major cause of the heart problem.

Early diagnosis will help reduce the cost of treatment…

Also, if you let the condition linger without treatment, you’d have to shell out more as the veterinarian address the health complications.

Nevertheless, most pet insurance covers several heart problems. However, if your doggo had CHF as a pre-existing condition during the purchase of the policy, it will not be covered. Also, some pet insurance companies will not answer to congenital defects.

Anyway, each insurance company will have varying inclusions. Make sure that you check the fine print before putting your money on it. 

How to prevent heart problems in dogs

Knowing what causes congestive heart failure in dogs can be difficult. Also, treatment can take its toll on your pocket. So while your pooch is in good shape, it’s best to keep their heart healthy. The following are some of the valuable tips you can do:

-Weight management

A very obese dog has a high risk of developing congestive heart failure. The extra fats that surround the heart will put pressure on the internal organ, causing poor circulation. This is why weight management has a direct impact on your pet’s heart health.

Practice portion control and avoid giving table leftovers to your dog. Your pooch may hate you a bit, but you’re doing it for their own sake.

-Proper nutrition

Giving your pooch heart-healthy foods is helpful in preventing heart problems. Avoid giving very salty food and make sure that your pooch is well hydrated.

Also, watch your dog’s fat intake and try to give them food rich in Omega-3 fatty acids. The likes of Vitamin C and E are also ideal in keeping your dog’s heart and immune system healthy. 

If you’re not sure, you can always ask your dog’s vet or a pet nutritionist.

-Regular vet visits

Nothing beats the expertise of a veterinarian when it comes to diagnosing health problems earl. Yearly general checkups are ideal to be on top of your dog’s health.

If something’s off, the vet can administer treatments right away. This will prevent the worsening of the condition, which will improve your pet’s quality of life.

-Enough exercise

Enough and proper exercise is crucial to keep your dog’s heart healthy. Sufficient cardio will exercise the heart muscles and keep it in good shape. This way, the heart can pump blood better to reduce the risk of CHF. Daily walks, swimming, playing, and hiking are just some of the great things you can do with your dog.

Still, you should choose the right activities for your dog. The goal here isn’t just for your dog to run out of breath. Remember that improper exercise is a risk factor in CHF.

We also recommend that you have your dog checked for heart murmur or CHF. This way, you won’t be fueling the condition by engaging your dog in tiring activities.

-Prevent parasites

Parasites aren’t just exclusive on your dog’s stomach; it could also wreak havoc on its heart. The likes of heartworm are dangerous and could weaken your pet’s heart. By preventing and treating parasites, you’re reducing your dog’s risk of heart disease by 13%.

-Healthy dental hygiene

Never underestimate the harm that dental problems can do on your dog. Poor dental health is directly linked to heart problems as sores and open wounds in the mouth can be a gateway for infection.

Final words

Knowing what causes congestive heart failure in dogs is the first step in improving your dog’s quality of life. There’s no cure for CHF right now, but the early diagnosis will help prolong your pet’s life. Also, as the pet owner, it’s your responsibility to ensure that your dog is in good health.

Vet visits, proper diet, and enough exercise are good ways to keep a healthy dog heart. Being proactive also pays off.