Congestive Heart Failure in Dogs

Boston Terrier having their heart listened to by a vet
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Congestive heart failure is a severe condition that can affect dogs, cats, and humans. CHF occurs as a complication of heart disease. Prompt treatment is necessary to relieve discomfort, ease breathing, and prevent death.

What is Congestive Heart Failure in Dogs?

Congestive heart failure is a syndrome that occurs when heart disease advances. CHF is not a disease itself but a syndrome characterized by fluid accumulation caused by heart disease. Specific signs vary depending on which side of the heart is diseased. Congestive heart failure may affect both sides of the heart if there are problems in both the left and right ventricles.

How the Heart Works

The heart is comprised of four chambers: the right atrium, the right ventricle, the left atrium, and the left ventricle. There are valves between these chambers that regulate blood flow through the heart. In a normally functioning heart, the veins of the body deliver deoxygenated blood through the right atrium into the right ventricle. The blood flows through the pulmonary artery and becomes oxygen-rich. The blood is then pumped into the left ventricle and then goes through the left atrium out to the body via the arteries. When a disease is present in one or more areas of the heart, the blood cannot flow properly and fluid can build up in the heart and surrounding areas.

Left-Sided Congestive Heart Failure

Left-sided CHF causes pressure to back up in the vessels that pump blood into the left ventricle of the heart. Fluid accumulates in the lungs (pulmonary edema) and leads to coughing, exercise intolerance, difficulty breathing, and high respiratory rate.

Dogs with left-sided CHF may collapse because obstructed blood flow leads to low blood pressure, slowed heart rate, and decreased oxygen supply to the brain.

Conditions like dilated cardiomyopathy, hypertrophic cardiomyopathy, mitral valve disease, and several congenital defects affect the left side of the heart and can lead to left-sided CHF.

Right-Sided Congestive Heart Failure

Right-sided CHF causes pressure to build up in the vessels where blood flows into the right atrium from the veins in the body. This pressure can lead to fluid build-up in the chest cavity, the abdomen (called ascites), the liver, and even the limbs. These dogs can experience difficulty breathing due to pressure around the lungs.

Ascites causes a bloated appearance to the abdomen. The pressure in the abdomen can affect breathing, digestion, and organ function. Limb swelling (peripheral edema) may also be seen when a dog has right-sided CHF.

Diagnosis and Treatment of Congestive Heart Failure in Dogs

Heart disease may be discovered after a routine examination reveals a heart murmur. Although most dogs in congestive heart failure will show some signs of illness, early disease may not be apparent until the veterinarian listens to the heart.

If your dog has already been diagnosed with some form of heart disease, then it is extremely important to see your primary vet or veterinary cardiologist regularly to monitor the progression of the heart disease. Signs of CHF may be detected before outwards signs are present.

Diagnostic tests used to detect and monitor heart disease include the electrocardiogram (ECG or EKG), echocardiogram (ultrasound of the heart), and thoracic radiographs (chest X-rays). Your vet will need to periodically repeat these tests to assess the severity of heart disease.

Treatment of CHF is aimed at managing the underlying heart disease and reducing fluid accumulation. Several different medications are typically used to treat heart disease and may need to be adjusted when CHF develops. Surgery may be recommended if there is a structural abnormality in the heart that can be repaired. A low-sodium diet can also be helpful.

Most cases of left-sided CHF are treated with diuretics. Other heart medications may be used as well.

In right-sided CHF, excess fluid may be manually removed, or "tapped," from the abdomen and/or chest cavity. Chest and abdominal taps can provide temporary relief, but the underlying heart disease will cause the fluid to reaccumulate. These dogs often need regular taps of the fluid to maintain a good quality of life.

How Long Can Dogs Live With Congestive Heart Failure?

The life expectancy of dogs with congestive heart failure depends on the underlying heart disease. CHF cannot be cured unless the primary heart disease can be cured. If corrective surgery can be done to fix the heart disease, then the dog may be able to go on to live a normal life.

Unfortunately, many types of heart disease can only be managed for so long before they become severe enough to stop responding to treatment. Dogs are in end-stage congestive heart failure when they no longer respond to available treatment options. These dogs may only have weeks to months left before they die from CHF or must be humanely euthanized due to poor quality of life

How to Help Your Dog With Congestive Heart Failure

The best thing you can do for your dog with congestive heart failure is to comply with veterinary recommendations and stay in communication with all veterinarians who treat your dog. Give all medications as directed on a regular schedule and do not make adjustments without your vet's recommendation. Feed a diet according to your vet's instructions and avoid salty treats as they can make your dog worse. Monitor your dog's signs at home and report changes to your vet immediately.

Although your dog may eventually succumb to congestive heart failure despite best efforts, it can offer peace of mind knowing you provided a good quality of life until the end.