Congestive Heart Disease in Dogs

Heart disease in dogs is common, especially in geriatric animals. Congestive heart disease occurs when your dog's heart's capacity to contract diminishes and your dog's heart can no longer pump blood as well as is should, leading to a back up of fluid in your dog's chest cavity. This fluid puts pressure on your dog's heart, and sometimes on his lungs, and can lead to a type of heart failure called congestive heart failure.

How a Healthy Dog Heart Functions

Your dog's heart is the pump that moves blood throughout his circulatory system. The right side of your dog's heart is smaller and less powerful; that side of the heart takes de-oxygenated, carbon dioxide rich blood from your dog's body and sends it, a low pressure, into the lungs where it picks up more oxygen. The left side of your dog's heart is stronger and more powerful; it sends oxygenated blood back into your dog's body.

Each side of your dog's heart has two chambers, an atrium and a ventricle. Blood enters the heart through the atrium, and then travels into the ventricle. A contraction of the ventricle sends blood back out of the heart, whether to the lungs or to the body. A valve between the atrium and ventricle stops blood from flowing backwards through the chambers of the heart.

Congestive Heart Disease

Congestive heart disease in dogs means that your dog's heart can no longer pump blood in the right volume or under the right amount of pressure. When the amount of blood getting pumped out of your dog's heart decreases, the amount of blood coming in increases. When this happens, fluid builds in the vessels and tissues upstream of the heart, and as the pressure increases, heart function suffers more.

Causes of Canine Congestive Heart Disease

Congestive heart disease in dogs can have a number of causes, but generally this disease is the result of one of two common causes, which are Degenerative Valvular Disease (DVD) and Dilated Cardiomyopathy (DCM).

Degenerative Valvular Disease weakens the valves between the chambers of your dog's heart. When this happens, the valves can no longer stop blood from flowing backwards through your dog's heart. As a result, blood begins to accumulate in the tissues of the chest cavity.

Dilated Cardiomyopathy occurs when one or both of the ventricles in your dog's heart begin to get bigger. As a result, the muscles walls of these heart chambers weaken and the ventricles are no longer able to pump blood as effectively as they did before. As the ventricles get weaker, they're able to pump less and less blood out of the heart. This leads to congestion upstream of the heart as blood accumulates there.

Symptoms of Congestive Heart Disease in Dogs

Vets don't yet know exactly what causes canine congestive heart disease. However, no matter the cause, symptoms remain similar. They include:

  • Sleepiness
  • Coughing
  • Lowered appetite
  • Fluid build up in the abdomen
  • Lack of energy
  • Fainting
  • Difficulty sleeping

Vets can administer a variety of medications to treat canine congestive heart disease, however, there is no cure.