Inherited infantile dilated cardiomyopathy in dogs: Genetic, clinical, biochemical, and morphologic findings

Dilated cardiomyopathy, a lethal disease characterized by left ventricular dilation and systolic dysfunction, is relatively common in humans and other mammals. Idiopathic dilated cardiomyopathy (IDCM) is a primary myocardial disease of unknown cause and can be a familial disorder. This report descri bes autosomal recessive IDCM in dogs. It occurs in Portuguese Water Dog (PW D) pups and is manifested by acute, vague clinical signs and sudden death. Affected pups have progressive reduction of fractional shortening that can be demonstrated by echocardiography prior to the development of clinical si gns. Furthermore, these pups have low plasma taurine levels when consuming certain diets. Affected pups had dilation of the left ventricle and alterat ions in the sarcomere appearance, while immunohistochemical and biochemical studies demonstrate an increase in desmin, a cytoskeleton protein. The cli nical and morphologic findings of IDCM: in PWDs are distinct from those rep orted in adult IDCM. Finally, the clinical and echocardiographic manifestat ions were reversible in some pups following oral taurine supplementation fo r 2 months. These results suggest that IDCM in PWDs is correlated with low plasma taurine levels. (C) 2000 Wiley-Liss, Inc.