The heart is responsible for pumping blood throughout the body. When it is unable to do so at level sufficient to support normal bodily functions, heart failure is the result. Congestive heart failure occurs when fluid leaks out of the circulatory system and collects in various parts of the body. Middle-aged and older animals are more commonly afflicted with diseases of the heart muscle (e.g., cardiomyopathies) or valves, but young animals can have birth defects or infections (e.g., heartworm disease) that also lead to heart failure.
Dogs and cats with congestive heart failure often cough, breath rapidly and with a greater effort than is normal, are weak and tire easily, and may have a distended abdomen. X-rays, also called radiographs, are often the first test used to differentiate congestive heart failure from other conditions that cause similar symptoms. Blood work, EKG monitoring and an ultrasound of the heart may be necessary to uncover the cause of congestive heart failure and to determine the best course of treatment.
In some cases, such as with heartworm disease or some congenital heart defects, an underlying problem may be able to be directly addressed and the congestive heart failure will resolve as a result. More frequently, however, congestive heart failure is managed with drugs that improve heart function and remove fluid from the body. In all but the most severe cases, animals tend to respond well to these medications, but dosages and combinations have to be continually adjusted and monitored as heart failure progresses. At some point, heart function usually declines to the point where even with aggressive treatment, the animal's quality of life become unacceptable.
Written by: Jennifer Coates, DVM
Last reviewed: October 2, 2008