A Matter of the Heart – Congestive Heart Failure (CHF)

Your dog most likely holds a special place in your heart. And one of your responsibilities as his owner is to keep his heart healthy. Unfortunately, the heart is an organ that frequently fails in dogs and millions of dogs examined each year have some form of heart disease. One major threat to your dog's health is heart failure.

Heart failure is a condition caused by an abnormality in the structure or the function of the heart. The heart is a pump. And when it fails it is unable to pump normal quantities of blood to the tissues of the body. Often heart failure leads to fluid retention in the lung and the body cavities leading to the condition called "congestive heart failure."

There are many causes of heart failure in dogs, including: birth (congenital) defects of the heart, degeneration of the heart valves, heart muscle disease (cardiomyopathy), heartworm disease,

diseases of the pericardium (the lining around the heart), and irregular electrical rhythms of the heart (arrhythmia).

Dogs of any age and any breed can develop heart failure. There is certainly a predisposition for heart failure caused by cardiomyopathy in giant canine breeds. Many older, small breed dogs develop heart failure from abnormal function of the heart valves as the valve tissue degenerates.

Heart failure affects your dog by reducing the amount of blood that is pumped to the muscles, leading to fatigue. In addition, most cases of heart failure are associated with accumulation of fluid in the lungs (pulmonary edema), the chest cavity (pleural effusion), or the abdominal cavity (ascites). This fluid accumulation can lead to shortness of breath and other problems such as coughing and difficult breathing.

What To Watch For

Some of the symptoms of heart failure, and the progression of heart failure in a dog, are related to increased activity of the nervous system and to increased concentrations of circulating hormones (and related chemicals). These include:

Coughing

Shortness of breath

Difficult breathing (dyspnea)

Weight loss

Fatigue

Diagnosis

Your veterinarian may suspect CHF after examining your pet, but he will probably run sever diagnostic tests to confirm the diagnosis and underlying cause. Tests may include:

General physical examination with emphasis on stethoscope examination (auscultation) of the heart and lungs

A chest radiograph (X-ray)

Measurement of blood pressure

An electrocardiogram (EKG)

Ultrasound examination of the heart (echocardiogram)

Treatment

Treatment for congestive heart failure will vary depending on the underlying cause. This may include one or more of the following:

Initial treatment may require hospitalization with a diuretic, oxygen, and other drugs such nitroglycerine paste.

A diuretic ("water-pill") such as the drug furosemide (Lasix®)

Pleural effusion (fluid around the lungs) may require drainage using a small needle in a treatment called "thoracocentesis." This often improves breathing and makes your dog more comfortable.

Nitroglycerine, which comes in the form of a paste, is often used topically (spread on the ear or abdomen or other relatively hairless area).

Other diuretics, such as spironolactone.

Angiotensin converting enzyme inhibitor such as enalapril (Enacard) or benazepril. These drugs block some of the harmful hormones that circulate in heart failure and prevent salt retention.

A diet limiting sodium intake and preventing fluid retention.

Use of digoxin (Lanoxin; Cardoxin)

Dietary supplements

Home Care

At home, administer all veterinary prescribed medications on a regular basis. Be aware of your dog's general activity, exercise capacity and interest in the family activities. Keep a record of his appetite and ability to breathe comfortably (or not), and note the presence of any symptoms such as coughing or severe tiring.

Do not stop medication or change the dosage without checking with your veterinarian. Most medications are for the life of your dog. And never withhold water, even if your pet urinates more than normal, unless specifically instructed to do so.

Difficult breathing is usually an emergency. See your veterinarian immediately.

Preventive Care

In general, heart failure cannot be prevented, although early diagnosis of the underlying cause can provide an improved quality of life. Once diagnosed, you should prevent excessive physical activity or excitement, avoid high heat/humidity and avoid high salt (sodium) foods or treats.

To learn more about congestive heart failure in dogs, please click on Congestive Heart Failure in Dogs.