Dominant myocardial disease diagnosed by fetal presentation of proband with an aneurysm of the muscular interventricular septum

We describe an inherited form of a disorder in which four patients spanning three generations were affected with congenital myocardial disease. The youngest member of the family, diagnosed as a fetus with a large aneurysm of the muscular interventricular septum, demonstrates an antenatal pathogenic process. Study of the specific findings in each patient suggests that congenital aneurysms of the muscular interventricular septum may be in some way associated with specific developmental pathways of the heart. We believe that screening family members of patients with muscular interventricular septal aneurysms may be indicated to assess for silent myocardial disease.