How to Manage Canine Congestive Heart Failure

Congestive heart failure in dogs is a condition that tends to affect middle-aged to older dogs and significantly impacts their quality of life.

Symptoms may be mild, to begin with, but inevitably advance over time. Lifestyle changes and medication are usually available to keep dogs more comfortable.

This article discusses what can cause heart failure, how to recognise the clinical signs, and what can be done to manage affected canines. How a dog is affected and their response to therapy will depend on how advanced their cardiac disease is and what is causing it.

What is Canine Congestive Heart Failure (CHF)?

When the heart can no longer pump adequately, fluid builds up in the chest and abdomen, and dogs have trouble breathing.

How CHF Develops

Typically, heart failure worsens slowly over time as the heart struggles to perform its function, and fluid slowly builds up in places where it shouldn’t be found.

Generally, the affected dog has an underlying cardiac condition, such as Dilated Cardiomyopathy (DCM) or Mitral Valve Disease (MVD).

Common Breeds and Risk Factors

Any dog can develop CHF, but specific individuals are at higher risk than others.

The King Charles Cavalier Spaniel is the ‘poster child’ for heart failure, as nearly all of them will have developed it by age 10.

Breed and genetics certainly play a huge role when it comes to heart disease. Still, the rate of occurrence also depends on things like body condition score, diet, hypertension, and other underlying medical issues, such as kidney disease or lung disease.

Causes of Canine Congestive Heart Failure

CHF has a range of potential causes, and uncovering why it is happening is important to determine the best course of treatment.

Valvular Disease

Mitral valve disease tends to occur in older and smaller breed dogs. As the valves degenerate, the blood no longer flows efficiently, and the turbulence means there will be an audible heart murmur.

Dilated Cardiomyopathy (DCM)

We see DCM more often in large, giant breeds like Dobermans, Great Danes, Boxers, and Cocker Spaniels.

As the heart muscles weaken and the chambers enlarge, the heart struggles to pump blood.

Heartworm Infection (and Its Role in Heart Failure)

Heartworms cause physical damage to the heart, blood vessels, and lungs.

They grow and breed, greatly increasing the strain put on the heart and even blocking off blood vessels and filling up the heart chambers. Pets who have travelled outside of the UK could be at risk.

Other Contributing Factors

Inevitably, higher blood pressure will put a strain on the heart, weakening the muscles. Similarly, any congenital defect that leads to abnormal blood flow or extra pressure on the heart is going to increase significantly the risk of CHF developing over the dog’s lifetime.

Symptoms of Canine Congestive Heart Failure

We tend to find that symptoms develop insidiously, and some owners can overlook the early signs.

Coughing and Difficulty Breathing

Coughing is a key finding in dogs with heart failure, though it has plenty of other causes, particularly in older canines.

A canine cough can sound like a gag or retch, and it is not uncommon for owners to think their dog has something stuck in their throat.

Any trouble breathing is a red flag and needs urgent investigation by an emergency vet. This may present as wheezing, rapid and shallow breaths, or abdominal effort while breathing.

Lethargy and Exercise Intolerance

Dogs may get out of breath and tire much sooner when exercising. You may notice they start panting quite early on in their walk. They may also seem weaker and less able or eager to play.

Changes in Appetite or Weight

Interestingly, some owners mistake the swollen abdomen that occurs with heart failure for weight gain. While extra fluid may lead to some weight gain, these dogs will generally lose muscle and fat and will eat less. These present as more prominent bones, particularly over the back and hips.

Swollen Abdomen or Distended Veins

The buildup of fluid is not visible in the chest but does lead to a big pot belly.

Due to the blood backing up and the pressure from the excess fluid, the veins may appear more prominent in the belly and neck.

Diagnosis of Canine Congestive Heart Failure

A vet is usually suspicious of the diagnosis after examining the dog and listening to its history. Still, tests will be needed to confirm the diagnosis and determine the extent of the disease and what caused it.

Veterinary Examination

Your vet will check your dog from nose to tail and pay attention to their breathing when standing still. They’ll listen to their heart and lungs with their stethoscope, as well as check their pulses and feel for any fluid within the abdomen.

Your vet can also assess circulation by checking the capillary refill time. They will press the gums until they go white and then assess how long it takes for them to become pink again. Anything less than two seconds is considered normal.

Diagnostic Tests

Several tests can be done to assess cardiac health, including:

• An ECG to measure electrical activity
• A thoracic X-ray
• An echocardiogram (ultrasound of the heart)
• Blood pressure measurement
• Blood tests to check cardiac biomarkers

Staging Heart Failure

We use an A, B, C, and D staging system for canine heart disease and CHF.

Stage A: At-risk dogs with no evidence of heart disease. These dogs should have routine checkups and should include breeds like the King Charles.

Stage B: These dogs have some abnormalities (like a heart murmur) but no signs of heart failure. Furthermore, there is a B2 class of dogs with heart enlargement.

Stage C: Symptoms of CHF are now present. There is fluid in the chest, known as pulmonary oedema, thanks to left-sided heart failure. There may also be fluid in the abdomen and limbs due to right-sided heart failure. These patients should be started on medication, such as diuretics and ACE inhibitors.

Stage D: These dogs are in end-stage heart failure, and the medication no longer controls their symptoms. They often have excess fluid in their chest and abdomen, and quality of life is likely poor.

Treatment Options for Canine Congestive Heart Failure

Though heart failure cannot be cured, there are many things you can do to help your dog cope and slow down disease progression.

Medications

Once in stage B2 or higher, it is advised that your dog starts on medicine to support its cardiac function and slow the progression of the disease. The type and dose of medicine your dog requires will depend on a range of factors.

We tend to see these patients regularly in the clinic so we can adjust their medication plan to ensure they are not being over- or under-medicated.

The more common medications prescribed include diuretics (to drain excess fluid), ACE inhibitors (to relax blood vessels), and Pimobendan (to increase the force of heart contractions and decrease its workload).

Dietary Management

It is advised that these dogs maintain a low-sodium diet. Prescription diets are available, and owners should avoid high-salt treats such as sliced meat and cheese. They should also provide highly digestible proteins to prevent muscle wastage.

Nutrients such as Taurine, omega-3 fatty acids, and antioxidants may all contribute to better cardiovascular health.

Lifestyle Adjustments

We want to ensure that our dogs stay active, but take it easy. This means consistent but low-intensity exercise that they can tolerate.

Your dog will be less able to cope with hot or humid weather and should not exercise in these conditions. You’ll also need to keep them cool indoors in the summer months, which can mean trimming fur short, using fans, and providing cooling beds.

Maintain a healthy body condition score, as being obese puts extra pressure on the heart, and can also lead to overheating in warmer weather.

Try to minimise stress, which can mean avoiding known anxiety triggers and keeping routines predictable and consistent.

Advanced Interventions

Some dogs will need more intensive care at times. This can include hospital admission and oxygen administration during stress or overheating. It can also mean injectable medicine if signs are not being well controlled with oral medicine.

When a dog is no longer responding to therapy as expected, we may need to opt for a higher dose or alternate medicine, such as alternative types of diuretics.

In the later stages, some dogs will have fluid drained using a needle to relieve pressure and ease breathing. Sadly, canine euthanasia would be something that needs to be considered at this point.

Home Care and Monitoring

You’ll soon become a pro when it comes to monitoring your dog, and knowing when they need a helping hand.

Keeping Track of Symptoms

A great way to monitor your dog’s stability is to measure its resting breathing rate regularly. This means counting how many times their chest rises and falls in one minute while they rest or sleep. Anything more than 30 times indicates an issue.

You should also be watching for signs, including persistent coughs, episodes of weakness, or grey gums. If your dog is coughing more than usual, this is likely a sign that their condition is deteriorating.

Monitoring Weight and Fluid Retention

In addition to keeping track of your dog’s weight on the scales, it is a good idea to learn how to evaluate its body condition score.

If your dog has a swollen abdomen, it means it is retaining more fluid than it should. This can cause weight gain, even when it is losing fat and muscle mass.

Creating a Comfortable Environment

A donut bed can be useful for those who struggle to catch their breath while sleeping. This is especially true for brachycephalic breeds, as it enables them to stretch out their necks when sleeping, allowing more space for air to flow.

We want to keep the home at a comfortable temperature and avoid excess humidity and heat. The air must also be well ventilated and free of dust, smoke, fragrances, and cooking fumes.

Regular Vet Check-Ups

Those with heart disease need to be seen regularly to monitor how they are coping and to alter their medication plan as required.

These checkups will usually include a chat with the vet and a physical exam, as well as tests such as heart scans and thoracic X-rays, so disease progression can be more accurately assessed.

Long-Term Prognosis and Quality of Life

Of course, every owner will want to know what a diagnosis of heart failure really means and how long they may have left with their beloved pet.

Frustratingly, these things are not always easy to estimate, and every dog is an individual when it comes to their response to therapy.

Factors Affecting Prognosis

Older dogs tend to cope worse, as they frequently have comorbidities.

The cause of heart disease is also a major factor. Heartworm is treatable, but if damage has been done to the heart, this won’t be reversible. Some congenital heart diseases can be rectified with surgery.

As a general rule of thumb, MVD has a better prognosis than DCM.

Improving Quality of Life

The best way we can help our furry friend is by having them regularly seen by their vet, providing therapy, and knowing when they are coping and not.

Palliative care can mean draining fluid and providing oxygen, but at this point, we need to consider if we are doing what is right for our dog.

We must closely monitor our dogs and their quality of life, that we are happy they are still enjoying life, and that the good days outweigh the bad. Once they reach the end of their lives, this needs to be reassessed daily or even more regularly.

Recognising When to Seek Emergency Care

Red flags that would warrant immediate assessment would include:

• Laboured breathing
• Breathing with an abdominal effort
• A prolonged capillary refill time
• A rapid resting heart rate
• Weakness
• Collapse
• Severe abdominal distension
• Seizures.

Preventive Measures for Congestive Heart Failure

For the most part, we cannot prevent heart disease in dogs. However, there are some things we can do.

Routine Parasite Prevention

Those in heartworm-endemic areas need to provide routine preventative therapy and minimise exposure to mosquitoes.

In the UK, owners should provide regular lungworm prevention and ensure their dogs are not exposed to slugs or snails (or the trails they leave behind).

Regular Veterinary Exams

We should see all dogs every year for their vaccines and regular health checks. When high-risk breeds reach middle age, it is sensible to have them checked every six months.

Those with a heart murmur also need to be seen every 6 months or so and should be presented to the vet promptly if they start to develop signs that could be consistent with heart disease.

Healthy Diet and Weight Management

Aiming to keep our dogs at a body condition score of about 4 out of 9 has many health benefits, including a lowered risk of cardiovascular disease.

We also want to avoid diets that are rich in sodium, and owners may consider supplementing their pooch with fatty acids and antioxidants.

Get Help With Canine Congestive Heart Failure

You are always welcome to contact us to discuss your dog and any concerns you may have about its heart health.

We’re here to guide you on how to best care for your furry friend and how to support them through a heart disease diagnosis.

FAQs

Is congestive heart failure in dogs curable or just manageable?

There is no cure for CHF, but lifestyle changes and medicine can help manage this disease for months or even years.

How can I tell if my dog is in the early stages of congestive heart failure?

Some earlier signs include a persistent cough and trouble keeping up during exercise.

What medications are prescribed for dogs with congestive heart failure?

Most dogs are given ACE inhibitors, diuretics, and Pimobendan. Your vet will determine which medicine your dog needs, and it depends on several factors.