Cardiomyopathy, Dilated, 1z

A number sign (#) is used with this entry because dilated cardiomyopathy-1Z is caused by mutation in the gene encoding slow troponin-C (TNNC1; 191040) on chromosome 3p.

For a general phenotypic description and a discussion of genetic heterogeneity of dilated cardiomyopathy, see CMD1A (115200).

Mogensen et al. (2004) studied a 3-generation family with severe dilated cardiomyopathy in which the proband had sudden onset of heart failure at 21 years of age and underwent cardiac transplantation 2 months later. His mother died at 45 years of age awaiting cardiac transplantation, his maternal grandfather died of heart failure at 62 years of age after 8 months of medical treatment, and a maternal aunt had unexplained sudden death at 21 years of age. A maternal uncle and cousin received cardiac transplants at age 52 and 22 years, respectively; the uncle, who had normal cardiac function at the time of his son's transplant, developed heart failure 2 years later and required transplantation within 2 months of symptom onset. The proband also had a younger sister diagnosed with CMD at 17 years of age who was being treated with angiotensin-converting enzyme inhibitors, and a younger brother who at age 36 years had left ventricular enlargement on echocardiography and ECG abnormalities. Histologic examination of specimens from an autopsy and an explanted heart showed nonspecific abnormalities including myocyte hypertrophy, increased interstitial fibrosis, and endocardial thickening with smooth muscle cells characteristic of CMD; there was no significant myocyte disarray characteristic of hypertrophic cardiomyopathy or features suggesting storage disease.

In 5 affected members of a 3-generation family with severe dilated cardiomyopathy, Mogensen et al. (2004) identified heterozygosity for a missense mutation in the TNNC1 gene (191040.0001).