Overview

Most cases are idiopathic. That is, the processes or insults ultimately leading to the morphologic diagnosis of DCM are unknown in most cases. As the heart has a limited number of responses to a variety of insults, the diagnosis of DCM often gives little to no insight into the underlying etiology with few exceptions.

• Taurine deficiency in some Cocker Spaniels.
• Taurine deficiency in some cases of unusual breeds (non giant breeds, non Dobermans).
• A mutation of the titin gene in Doberman Pinschers, in which the disease appears to have autosomal dominant inheritance.
• Tachycardia-induced. Any tachycardia (>240 bpm for >3 weeks) will cause a DCM-like picture.
• Doxorubicin-induced.
• Viral induced. We believe some cases of acute DCM might be viral-induced, particularly in young dogs.
• Role of carnitine: Work performed by Dr. Bruce Keene a number of years ago suggested that a deficiency of carnitine may be responsible for DCM in some Boxers. Carnitine is essential to transport fatty acids into the mitochondria of the muscle cell. Without adequate carnitine, fatty acids cannot enter the mitochondria, and energy deficiency results. However, carnitine presently does not appear to be responsible for most cases of DCM observed in Boxers or other breeds. Rather carnitine deficiency is likely a secondary effect in heart disease and not a primary cause.