Why Does My Dog Cough And Gag When He Has Congestive Heart Failure?

Overview of Congestive Heart Failure in Dogs

Congestive heart failure (CHF) is a condition in which the heart cannot pump enough blood to meet the body’s needs. It is fairly common in dogs, affecting an estimated 10% of dogs overall and 75% of senior dogs.

CHF occurs when the heart is damaged or diseased, causing it to weaken and become enlarged. This leads to improper function, where the heart cannot efficiently pump blood throughout the body. The most common causes of CHF in dogs are chronic valve disease (endocardiosis), dilated cardiomyopathy, and myocardial failure.

As the heart struggles, pressure builds up in the blood vessels and fluid leaks into the lungs or other tissues. This buildup of fluid is what causes “congestion,” leading to common symptoms like coughing, shortness of breath, lethargy, and fluid buildup in the abdomen or limbs.

CHF is a progressive, chronic condition. However, with early diagnosis and proper treatment, symptoms can often be managed to improve quality of life. The prognosis depends on the underlying cause and severity, but dogs can sometimes live with CHF for many months or even years with lifestyle adjustments and medical management.

Symptoms of CHF in Dogs

Congestive heart failure causes a buildup of fluid in the lungs and chest cavity, leading to some key symptoms in dogs. The most common symptoms of CHF in dogs are persistent coughing and gagging, breathing difficulties, and extreme fatigue.

Coughing and gagging are perhaps the most notable symptoms of CHF in dogs. The fluid buildup in the lungs causes dogs to cough frequently as if trying to clear their airways. The cough is often soft and wheezy sounding. Dogs may also gag or try to vomit as they struggle to breathe normally. These coughing and gagging episodes can occur randomly or be triggered by any activity requiring exertion.

In addition to coughing and gagging, dogs with CHF struggle with labored breathing. They may pant heavily even when resting. Some dogs adopt a standing position with elbows held wide, as if trying to expand their chest cavity to breathe easier. The accumulation of fluid compresses the lungs, making it very difficult for dogs to get enough oxygen.

As a result of poor oxygen circulation, dogs with CHF often experience pronounced lethargy and fatigue. They tire extremely easily from any physical movement. Even everyday activities like going up steps or short walks outside can be exhausting. Dogs may isolate themselves and sleep much more than usual due to this fatigue.

Other symptoms like fainting, back leg weakness, distended abdomen, and exercise intolerance can also occur with CHF. However, the persistent coughing/gagging and breathing difficulties tend to be the most common and prominent signs of congestive heart failure in dogs. If these symptoms arise, especially later in life, schedule a veterinary visit promptly for evaluation.

Coughing and Gagging Explained

When a dog has congestive heart failure, fluid can start to build up in the lungs. This excess fluid puts pressure on the airways, causing irritation, inflammation, and difficulty breathing. The dog’s body tries to expel the fluid and clear the airways by coughing and gagging. According to VCA Animal Hospitals, coughing is one of the main symptoms of congestive heart failure in dogs.

The coughing and gagging associated with CHF tends to be persistent and chronic. It may start out soft and intermittent, but can progress to loud, frequent coughing fits as the condition advances. Dog owners may notice that their pet’s cough seems worse at night or first thing in the morning. This is because fluid accumulates in the lungs when the dog is lying down.

Some dogs may make a wheezing, raspy noise when breathing, which indicates narrowed airways. They may gag repeatedly like they are trying to clear something from their throat. According to Dogster.com, some dogs with CHF will extend their necks and lean forward when they cough, in an attempt to expand their airways. All of these signs point to fluid buildup in the lungs causing irritation, inflammation, and airway obstruction.

Stages of CHF

Congestive heart failure in dogs progresses through four stages:

Occult Stage

In the occult or preclinical stage, a dog’s heart function starts to deteriorate but there are no symptoms. This stage may last for years before progressing.

Asymptomatic Stage

As heart function worsens, the body compensates to preserve normal function. At this stage dogs can appear completely normal and healthy despite the underlying disease.

Early Symptomatic Stage

As compensation mechanisms begin to fail, early symptoms start to appear like reduced exercise tolerance, coughing, or trouble breathing. These may come and go at first.

Advanced Stage

In the advanced or overt stage of CHF, symptoms are obvious and severe. Fluid builds up leading to coughing, gagging, labored breathing, loss of appetite, and even fainting.

Veterinary attention is crucial once CHF reaches the symptomatic stages. Early diagnosis and treatment can help dogs live comfortably for some time.

Diagnosing CHF

There are several tests a veterinarian will perform to diagnose congestive heart failure in dogs:

Physical exam – The vet will listen to your dog’s heart and lungs with a stethoscope. They will check for any heart murmurs, abnormal lung sounds, or abnormal heart rhythms that could indicate heart disease. The vet will also check for signs of fluid accumulation like swelling or distended abdomen.[1]

Chest x-rays – Radiographs allow the vet to see the heart size and shape and look for signs of fluid in or around the lungs. Enlarged heart, fluid accumulation in the lungs, and pulmonary edema are hallmark signs of congestive heart failure.[2]

Blood tests – Blood work evaluates organ function, electrolyte levels, and identifies anemia or infection. These can aid in determining if heart failure is present. Specific heart tests like proBNP can also help confirm CHF.[3]

Treating CHF

There are several aspects to treating congestive heart failure in dogs, including medications, diet changes, and oxygen therapy.

Medications commonly prescribed for dogs with CHF include:

  • Diuretics like furosemide to reduce fluid buildup and ease breathing (Source)
  • ACE inhibitors like enalapril or benazepril to relax blood vessels and improve heart function (Source)
  • Pimobendan to enhance heart contraction and prevent heart enlargement (Source)

Vets may also recommend diet changes like reduced sodium to decrease fluid retention and strain on the heart.

Oxygen therapy can be used to improve oxygen circulation and relieve respiratory distress. Dogs with CHF may benefit from an oxygen cage or mask to aid breathing.

Additional medications or treatments may be prescribed based on the dog’s symptoms and stage of CHF.

Lifestyle Changes

Making some adjustments to your dog’s lifestyle can help manage congestive heart failure and improve their quality of life. Two key areas to focus on are exercise restrictions and reducing stress.

Dogs with CHF have decreased stamina and get fatigued more easily. They should avoid strenuous activities like running and jumping. Short, gentle walks are usually fine, but check with your vet on an appropriate exercise plan. Some dogs do well with multiple short walks per day rather than one long walk. Pay attention to signs of fatigue like panting, reluctance to move, or lying down during walks. Allow your dog to rest as needed.

Stress can worsen signs of heart disease, so creating a predictable, low-stress environment can help. Reduce loud noises, changes in routine, and interactions with other pets or children that might overexcite your dog. Make sure your dog always has access to fresh water, their own quiet space, and comfortable bedding. Consider calming supplements or pheromone diffusers if your dog is very anxious.

While exercise and excitement restrictions can be challenging, they are important to manage congestive heart failure. Work closely with your veterinarian to find the right balance for your dog’s needs.


The prognosis for dogs with congestive heart failure depends on the underlying cause and how advanced the disease is. However, with treatment, the median survival time for dogs with advanced CHF is around 9 months.

For dogs with mitral valve disease, the average survival time after being diagnosed with CHF is approximately 9 months, with a wide variation from 3 months to over 3 years. Smaller dogs tend to live longer than larger breeds with CHF.

With treatment and close monitoring, dogs can often enjoy a good quality of life for many months before the disease progresses to an advanced stage. However, owners should monitor their dog’s breathing, appetite, activity levels and overall comfort. As the disease advances, dogs may experience more labored breathing, loss of appetite, weakness, and exercise intolerance.

In the end stages of CHF, dogs require higher doses of medication and may need supplemental oxygen. Euthanasia is often recommended when the dog has extremely poor quality of life despite medical therapy. Owners can help their dogs by providing soft bedding, keeping them calm and relaxed, and being with them during the final stages.

While CHF shortens a dog’s life expectancy, with treatment and dedicated care, dogs can live happily for as long as possible before reaching the advanced stages of the disease.

Preventing CHF

There are several ways to help prevent congestive heart failure in dogs:

Wellness Care

Getting regular wellness exams with your veterinarian is important to monitor your dog’s overall health and catch any potential issues early. Wellness visits typically include a physical exam, discussion of diet and exercise, bloodwork, and other screening tests. Following your vet’s wellness recommendations helps reduce risk factors for heart disease (Source).

Dental Health

Poor dental health can lead to bacteria entering the bloodstream and damaging the heart valves. Regular dental cleanings and brushing your dog’s teeth helps prevent bacteria buildup and reduces chances of developing heart disease down the line (Source).

Managing Other Conditions

Dogs with certain pre-existing conditions like hypothyroidism, diabetes, or Cushing’s disease are at higher risk for heart disease. Following your vet’s treatment recommendations for managing these chronic illnesses can help prevent added stress on the heart (Source).

When to See a Veterinarian

If your dog starts coughing or gagging suddenly, it’s important to have them seen by a veterinarian. Sudden coughing or gagging can be a sign that congestive heart failure is worsening. Fluid buildup in the lungs causes coughing and gagging as the dog tries to clear their airways. If not treated, this fluid buildup can become life-threatening.

Any breathing problems like labored breathing, wheezing or shortness of breath also warrant an urgent vet visit. Difficulty breathing is a common symptom of CHF as the heart struggles to pump blood effectively. The sooner treatment can begin, the better the outcome for dogs with CHF.

Loss of appetite is another reason to have your dog evaluated promptly. As CHF advances, dogs often lose their appetite as they become fatigued. It’s important to get to the root cause of appetite changes before your dog loses too much weight or becomes dehydrated.

In summary, sudden coughing or gagging, breathing issues, and loss of appetite are all signs that CHF may be worsening. Don’t wait to bring your dog to the vet – early intervention can help manage symptoms and improve quality of life. Call your veterinarian right away if your CHF dog experiences any of these symptoms. (VC Animal Hospitals)

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