Dilated cardiomyopathy and sinoatrial dysfunction in an Estrela mountain dog.

A 1 yr old male Estrela mountain dog was evaluated as a part of a screening program for dilated cardiomyopathy. The dog came from a family with a history of dilated cardiomyopathy but was asymptomatic. Occult dilated cardiomyopathy and sino-atrial dysfunction were diagnosed based on echocardiography and electrocardiography. These two disorders may be associated given that related dogs have been diagnosed with the same disorders. The dog has remained asymptomatic for 4 years following initial evaluation.