Congestive heart failure (CHF) is the result of an underlying heart disease that causes the heart to fail. Heart failure occurs when the heart is no longer able to effectively pump blood through the body and fluid then accumulates behind the failing pump—typically in/ around the lungs or in the belly. The most common examples of diseases with this outcome are degenerative valve disease (progressive changes in the heart valves that cause heart enlargement) in small breed dogs and hypertrophic cardiomyopathy (genetic based thickening of the heart muscle) in cats of all types.
Signs & Symptoms
In companion animals, the most common signs of CHF are coughing and breathing difficulties. Less commonly, animals may show signs of exercise intolerance, weakness, decreased appetite or bloating. The most effective way to discover subtle symptoms of congestive heart failure in companion animals is to monitor their breathing rates at sleep. The normal sleeping breathing rate in the dog and cat is usually less than 30-35 breaths per minute. If the breathing rate becomes elevated, contacting your care provider for medical treatment can avoid progressive heart failure and minimize the need for hospitalization.
Your primary care veterinarian will notice abnormalities as a part of the pet’s annual or every six-month wellness evaluation. If they find abnormal lung sounds, a heart murmur, arrhythmia, elevations in a blood test called NT Pro-BNP, or a veterinarian notices other heart-related problems, they then discuss referral to a board-certified veterinary cardiologist.
Treatment & Aftercare
There are many ways companion animals develop CHF and the treatment depends on the underlying condition. In cases of heart damage resulting from a very fast heart rate, an over-active thyroid, or a congenital heart defect, the congestion and cardiac damage may be almost reversible with appropriate care. Other heart diseases can be managed and potentially slowed down with medications but are not reversible.
Medications used to treat the congestive signs of heart failure in companion animals are the same medicines used for people with CHF. Drugs for decreasing fluid retention, dilating blood vessels, preventing blood clots and slowing heart rate are all in use in companion animal cardiology. These medications are readily available in pill or liquid forms and the majority in generic brands. Almost all owners are able to develop a system to get companion animals to take their medications on a daily basis.
The prognosis for companion animals with CHF varies widely with the underlying condition. The more specifically we can treat the underlying disease, the better the prognosis. In the worst cases, the expected lifespan may be as short as days to weeks while best cases are managed for many years. Veterinarians caring for companion animals with CHF work with individuals and families to provide their animals an excellent quality of life for as long as possible.
Bonnie Lefbom, DVM, DACVIM (Cardiology)