Congestive Heart Failure in Dogs

Congestive heart failure (CHF) is a common syndrome caused by heart dysfunction that causes fluid retention in the chest cavity. The area of fluid retention corresponds to which side of the heart is failing. CHF typically has a slow onset, with subtle early symptoms, but there are cases in which CHF is sudden in onset and an emergency.

Any dog that is showing signs of possible CHF needs to be evaluated by a veterinarian as soon as possible.Difficulty breathing is life threatening. Dogs in respiratory distress require immediate veterinary attention.

Prognosis of CHF is determined by what is causing the underlying cardiac disease, but all cases warrant a fair to guarded prognosis.

Any condition that decreases the capacity of the heart to pump blood through the circulatory system can lead to CHF. As the heart fails to efficiently pump blood, fluid backs up and leaks out of the circulatory system. Left-sided heart failure builds fluid up in and around the lungs. Vessels from most of the body drain into the right side of the heart so pets with right-sided heart failure most commonly accumulate fluid in the abdomen, liver, chest cavity, and the membrane around the heart.

Breed, sex, and age predisposition is related to the underlying cardiac disease which is causing the CHF.

General classifications of disease that cause CHF are degeneration, cardiomyopathies, or congenital disease.

Conditions associated with left-sided CHF are mitral valve disease, most dilated cardiomyopathies, hypertrophic cardiomyopathies, and most common congenital cardiac defects like a patent ductus arteriosus.

Right-sided CHF is associated with pulmonary hypertension, diseases of the pericardium, heart valve dysfunction, dilated cardiomyopathies, and heartworm disease.

Diagnostic testing includes:

• Blood tests, including a ProBNP test to identify heart muscle damage
• X-rays
• Electrocardiography
• Echocardiography
• Fluid analysis

Referral to a veterinary cardiologist is common.

Treatment is based on symptoms. Medications are most commonly started to help the heart function more efficiently and to decrease build up of fluid.

If a pet presents in respiratory distress, hospitalization may be needed until symptoms are manageable.

Monitoring and rechecks are necessary to optimize the treatment protocol.

Counting the sleeping respiratory rate at home is useful information for directing treatment.

CHF is a progressive disease and cannot be cured. Management of CHF is aimed at improving quality of life for as long as possible. Due to disease progression, medications eventually stop helping, which leads to eventual end-of-life care and euthanasia in most cases.

With one of the most common causes of CHF, mitral valve disease, mean survival time (MST) is generally less than two years.

CHF has many causes, and most cannot be prevented. Heartworm disease is one underlying cause that is easily prevented. Any breeding animal should be screened for the common cardiac conditions prior to breeding.

CHF is common in dogs.

• Medications
• Oxygen therapy
• Removal of excess fluid
• Ongoing monitoring