Congestive heart failure in dogs is a condition characterized by coughing, breathing difficulties, and other troubling symptoms. Today, our vets at Carolina Veterinary Specialists discuss the causes of congestive heart failure, symptoms to watch for, and available treatments.
Canine Congestive Heart Failure
Congestive heart failure (CHF) is a term that refers to the heart's inability to pump enough blood to the body. Due to this, blood starts to back up into the lungs and fluid accumulates in the chest, abdomen or both. This lead to further constriction of the heart and lungs, and limits oxygen flow throughout the body. There are many causes of CHF in dogs, but the two most common causes are:
- Mitral valve insufficiency (MVI), refers to a leaky mitral valve, which is the valve between the left atrium and the left ventricle.
- Dilated cardiomyopathy (DCM) occurs when the heart chambers enlarge and lose their ability to contract.
Clinical signs of CHF vary depending on whether the dog has left- or right-sided heart failure.
RS-CHF - Right-sided congestive heart failure
RS-CHF occurs when a heart contraction causes some blood to leak into the right atrium from the right ventricle rather than being pushed through the lungs and becoming oxygenated. As a result, the main circulation system becomes congested with blood, and fluid accumulates in the abdomen, interfering with adequate organ function. Excess fluid might also build up in the limbs and cause swelling known as peripheral edema.
LS-CHF - Left-sided congestive heart failure
LS-CHF is the most common type of congestive heart failure in dogs and occurs when blood from the left ventricle leaks back into the left atrium through the mitral valve rather than getting pumped into the body's systemic circulation when the heart contracts. As a result, causes pressure overload to the left side of the heart. Fluid begins to leak into the tissue of the lungs, causing swelling known as pulmonary edema, which leads to coughing and difficulty breathing.
Causes of Congestive Heart Failure In Dogs
The most common cause of congestive heart failure in dogs is congenital heart defects, meaning that it's an unpreventable genetic condition. Many small breeds have a genetic propensity toward CHF including toy poodles, Pomeranians, dachshunds, and cavalier King Charles spaniels. Small dogs in general tend to be more prone to developing CHF because their heart valves are more prone to degenerate than in larger breeds.
However, some large breeds, particularly giant breeds such as St. Bernards, Newfoundlands, and Great Danes are prone to developing CHF due to dilated heart muscles. It's important to understand that congenital CHF typically appears later in a dog's life and that these dogs can live many years seemingly healthy and happy before symptoms begin to show.
CHF can also develop in a heart that's been weakened by other heart conditions, so it's important to do what you can to prevent heart disease from occurring in your pet, including preventing obesity and providing heartworm prevention.
Signs of Congestive Heart Failure In Dogs
Below are some common symptoms that your dog might show if they are suffering from congestive heart failure:
- Constant panting
- Struggling to breathe
- Breathing at a fast rate, especially when in a resting state
- Reluctance or refusal to exercise
- Getting tired more easily on walks or during play
- Blue-tinged gums
- Distended abdomen
- Coughing up blood
If you notice any of these symptoms, you should have your dog checked by your vet without delay.
How To Diagnose Congestive Heart Failure In Dogs
- Blood and urine test
- Chest X-rays
- Heartworm antigen test
- Holter monitor
Treatment For Congestive Heart Failure In Dogs
So now that you have an understanding of what congestive heart failure is, what is the treatment for congestive heart failure in dogs?
Your dog will likely be placed on a number of medications. These include a diuretic to remove the excess fluid buildup in the lungs and body, an angiotensin-converting enzyme (ACE) inhibitor which has been shown to improve clinical symptoms and increase survival in dogs with CHF, and a vasodilator to relax the body's blood vessels. In some cases, another type of drug known as a positive inotrope might be prescribed to strengthen the force of contractions in the heart and improve blood flow.
If your dog is struggling to breathe, your vet may administer oxygen therapy until he's able to breathe adequately on his own. Depending on how much oxygen is needed, this might require hospitalization.
Congestive Heart Failure In Dogs Life Expectancy
Make sure to bring your dog for regular visits with your vet and stick with your treatment plan. Unchecked heart problems can make things harder on your dog and even shorten their life. With the right treatments, care, and monitoring, your dog can live a long, comfortable life.
Unfortunately, treating congestive heart failure in dogs is not curative. Your dog's treatment will be aimed primarily at improving quality of life and making your dog comfortable and happy. Advances in medications used to treat this condition have vastly improved the overall prognosis. Vigilant home care and lifestyle management may help to extend survival from months to years. The sooner this condition can be identified and treatment is started, the better the chances are of extending your dog's life.
Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.