The antenatal diagnosis of fetal atrial septal aneurysm.

Fetal atrial septal aneurysm (ASA) is uncommon and little is known regarding its prevalence and clinical significance. In this report we describe 2 cases of fetal ASA diagnosed by ultrasonography. They were referred for examination because of fetal tachyarrhythmia in 1 case, and polyhydramnios in the other. The first case had a normal outcome, while the other was associated with other congenital heart malformations. The literature as regards the diagnosis, prevalence, pathology, and clinical implications of ASA is discussed.