Mitral Valve Disease generally affects small breeds such as Dachshund, Beagle and Chihuahua. What is Mitral Valve Disease? Let us first define what mitral valve is. The heart has four chambers, the upper chamber called atria and the lower chamber called ventricles. It is also divided into right and left sides. Mitral valve is the valve located between the left atrium and left ventricle of the heart.



In most dogs, especially the small breeds like the Chihuahua, this mitral valve wears out because of the large pressure created when the left ventricle contracts. This wearing out results to a small leak and gradually gets more severe over time.

Dogs affected by mitral valve disease may exhibit some signs. Early signs include reduced tolerance for exercise, difficulties in breathing or cough especially during the night or at rest. These signs occur because of fluid build-up in the lungs. As the disease progresses, symptoms such as fainting, weakness or collapse may occur due to an abnormal heart rhythm.

Mitral valve disease is diagnosed in many ways. Using a stethoscope, veterinarians listen to murmur, abnormal heart rhythm and even lung sounds. The murmur ranges from soft to loud, holosystolic and is loudest at the apex over the mitral area. Electrocardiogram, also called ECG or EKG is also used in diagnosing mitral valve disease. Electrocardiogram is the measure of the activity of the heart and determines the heart rate whether arrhythmias exist. Chest radiographs or x-rays can also be used in determining this disease. Dogs affected by mitral valve disease may exhibit left atrial enlargement with or without left ventricular enlargement in their x-rays. The pulmonary veins are often enlarged too.

Is mitral valve disease curable? A concerned dog owner would possible ask this question. With the advancement of today's technology and medicine, more and more ailments can possibly be treated as long as it's not yet too late. However, replacing heart valve through surgeries is not possible in dogs. But drugs such as diuretics, nitroglycerin and digitalis help in improving the condition of the heart even with the existence of leaky valve. Diuretics work in stimulating the kidneys to remove excess fluid from the body. Nitroglycerin helps dilate the veins throughout the body and promote heart contractions. Digitalis on the other hand improves heart function by regulating excess hormones that have been released and strengthening each contraction of the heart. Restricting salt in your Chihuahua's diet also helps in combating this disease. This method works by preventing the retention of excessive fluid.

One important point to remember, dogs affected or show signs of mitral valve disease should not be included in any breeding process to prevent the occurrence of this disease in your pup.