Mitral Valve Disease (MVD) is the most common form of heart disease in dogs. It generally occurs in small to medium size dogs rather than big dogs, and some breeds are more susceptible than others. These breeds include: Cavalier King Charles Spaniel, Poodle, Schnauzer, Chihuahua, Fox Terrier and Boston Terrier.
Male dogs are more commonly affected than females. Also, it is mostly older dogs who tend to suffer from this disease, but some dogs are quite young when it begins to occur.
MVD is a disease that affects the surface of the heart valves. Other names you may hear used to describe MVD are endocardiosis or Valvular Insufficiency.
The valves are normally smooth and form a perfect seal when closed. MVD causes the edges to become thickened, lumpy and distorted. The seal is now imperfect and when the ventricle pumps, some of the blood flows backwards into the atrium. This backward flow creates a noise that your veterinary surgeon can hear with a stethoscope. The noise is called a murmur.
Because the heart valves are now leaky, circulation is impaired.
For a time your dog's body may make adjustments to allow it to cope. In fact some dogs manage with a murmur for many years. However, at some point, the disease overrides the adjustments that have been made and the dog can become unwell and show some signs of heart failure.
MVD may affect your dog's body in a number of different ways. See your vet for more information.