Dilated Cardiomyopathy (DCM) is a disease of the heart muscle. It is more common in medium to large breeds of dog rather than small dogs, and some breeds are more susceptible to the disease than others. These susceptible breeds include Doberman, Cocker and Springer Spaniels, Boxer, Irish Setters, German Shepherds, Great Danes, St Bernard and Irish Wolfhounds. Middle-aged male dogs tend to be most affected.

In DCM the heart fails to pump effectively. The contractions of the heart are weak and blood is not supplied to the body as efficiently as before. Also, the heart stretches and enlarges.

Because the heart's ability to pump is impaired, circulation is also impaired. For a time your dog's body may make adjustments to allow it to cope. However, at some point, the disease overrides the adjustments that have been made and the dog can become unwell and shows signs of heart failure.

DCM may affect your dog's body in a number of different ways. See your vet for more information.