Providing compassionate care for an important member of your family
D. Isabel Cole, DVM
Arrin M. Colgan, DVM
Heart Disease in Dogs and Cats
Heart disease, whether age-related or a congenital birth defect, can be managed with proper
diagnosis and treatment. Heart disease usually manifests itself with symptoms pertaining to the lungs.
Signs of heart disease include coughing, panting, decreased exercise tolerance, weakness, dizziness or
even fainting. A cat rarely pants unless it is very nervous – a cat panting after exercise should be
examined and have x-rays taken immediately! Heart disease may be diagnosed during a physical exam
by listening to the heart and lungs. Chest x-rays, often an EKG, and blood pressure monitoring can also
be performed. A heartworm test is often recommended as well.
When the heart is sick, it doesn’t pump effectively and “leaks” blood back into the heart
chamber–this is what causes a “murmur”. The heart tries to compensate by either pumping faster to get
the same amount of blood to the tissues or stretches to pump more blood in the same amount of time. As
the heart stretches, it enlarges which then “pushes up” on the major airway passages in the lungs, causing
coughing. As the heart fails, fluid will seep from the blood into the lungs reducing oxygen exchange
which leads to panting, weakness, and coughing.
Cats with heart disease tend to have thickened walls of the heart which impede the hearts ability
to fully relax. This is typically correlated to hyperthyroid disease in cats. Because the walls thicken (rather
than thinning and enlarging), it can be difficult to evaluate the heart size in cats with x-rays alone. Often,
an ECG or echocardiogram is required to determine the true extent of the disease. Cats heart disease are
also at a higher risk of having blood clots.
The goals of therapy are to increase the amount of oxygen in the blood, reduce or eliminate
coughing, and, if indicated, treat for secondary pneumonia caused by fluid in the lungs. Treatment may
also help slow down the progression of the disease. Here is our line of attack:

Furosemide, a diuretic to remove fluid. We start at an appropriate dose to control symptoms,
then adjust the dose to get maximum control with the least drug dose. Pets on furosemide
need to be monitored with blood tests.

Diet—a diet low in sodium with added potassium and B-complex vitamins is indicated such
as a prescription heart or kidney diet. We also advise weight loss if the pet is overweight.

Heart medication—there are a variety of medications available depending on the type of heart
condition. For example, some increase the strength of the heart pumping, while others slow
down the heart thereby increasing blood flow. Blood pressure medicine is prescribed if
needed. Some cats will need blood thinners to help prevent blood clots.

Supplements—Coenzyme Q10 is an essential enzyme that helps the heart muscle. Fish oil has
been shown to decrease inflammation and improve heart health.
The prognosis of an animal with heart disease varies. It depends on the underlying cause of
the heart disease and the severity as well as their response to medicine. Another important
consideration with heart disease includes the risk of anesthesia. Although there are increased risks due
to the heart disease, anesthesia is often necessary to perform certain procedures such as dental
cleanings. Dental disease allows bacteria into the body and the heart is often one of the most affected
organs and can cause further worsening of the heart disease. Once an animal with heart disease is
stabilized and responding to medicine, the risks of dental disease often outweighs the risk of
anesthesia.
908 E. Main St.
Urbana, IL 61802
Phone: 217-344-1017
Fax: 217-344-0654
office@goodfriendsanimal.com
www.goodfriendsanimal.com