Congenital aneurysm of the left atrium associated with double-outlet right ventricle in a trisomy-18 fetus: Case report and literature review.

Congenital aneurysm of the left atrium is a rare cardiac anomaly, most commonly detected between the 2nd and 4th decades of life in a symptomatic patient. We report a congenital aneurysm of the left atrium diagnosed at 24 weeks of gestational age, associated with other congenital heart diseases and 47XY, +18 karyotype. The literature of the left atrial aneurysm diagnosed by fetal echocardiography is also reviewed in this report.