Two young White brothers had dilated (congestive) cardiomyopathy. The elder came to autopsy after a chronic course of congestive cardiac failure, the younger underwent repeated cardiac catheterization and transvenous right ventricular endomyocardial biopsy specimens demonstrated histopathological features in keeping with a diagnosis of idiopathic dilated cardiomyopathy. These brothers may have the familial form of the disease, although post-viral myocarditis cardiomyopathy cannot be entirely excluded. The literature relating to familial dilated (congestive) cardiomyopathy is reviewed.