Prognosis for Leaking Heart Valve in Dogs

A leaking heart valve is the most common cause of canine heart failure. The prognosis depends on when the disease is first diagnosed.

Leaky heart valves are more common in small breeds. The heart disease is often diagnosed during a normal veterinary check up. Your veterinarian will hear a heart murmur through the stethoscope and run additional tests.

X-rays, ECG/EKG and echocardiograms are all useful tools in determining if a valve is leaking. Once the veterinarian has this information, a treatment plan can be discussed. A leaking heart valve is not a death sentence. Many dogs go on to live years with a leaky mitral valve.

What Causes a Leaking Heart Valve

The heart contains four chambers:

  • Left and right atria (upper portion of the heart)

  • Left and right ventricle (lower portion of the heart)

Blood comes into the atria from the body and then travels to the ventricle where oxygen from the lungs is added to the blood before it is pushed to the rest of the body. Between each side of the heart is a valve. The valve's goal is to ensure the blood moves from one chamber to the next.

In the left ventricle, the oxygenated blood is they pumped to the rest of the body. The valve connected to the left ventricle receives plenty of use becomes a leaking heart valve. Blood back washes into the other chamber causing the heart to beat inefficiently. Eventually, the amount of oxygenated blood declines leading to congestive heart failure.

Treatments for a Leaking Heart Valve

Surgical treatment of a leaking valve is not performed in dogs. There are medications that can help prolong a dog's life. Digitalis and beta blockers are useful in treating congestive heart failure. They help slow the heart rate, which, in turn, makes each heart beat more effective. The stronger the heart beats, the more oxygen makes it into the bloodstream.

Nitroglycerin helps open up veins in the body so that blood moves freely into and out of the heart. The body can build up a resistance to the medication. Vasodilators work in the same manner as Nitroglycerin, however it's uncommon for a dog to become resistant to the medication. They are better for long term use.

In cases of congestive heart failure, diuretics will help remove fluid from the body reducing the risk of an enlarged heart. The medication works by stimulating the kidneys. The more fluid that is filtered out through the urine, the healthier the dog will be. Putting your pet on a sodium-free diet also helps keep the body from retaining liquids.

Early Diagnosis Is Optimal

Catching a leaking heart valve in its earliest stages offers the best prognosis. Dogs diagnosed with Stage 1 are easily treated with prescription medications. If the condition isn't noticed until Stage 4, the dog's outlook may not be as positive.

Dogs in the earliest stages of mitral valve leaks go on to live years. Stage 4 dogs may only have weeks to live. Statistics are only a best guess, however. Some dogs with congestive heart failure caused by a leaky valve surprise everyone by surviving months to years on medications.