Type : Other, mainly phenotypes with suspected mendelian basis;
Description : Ebstein anomaly is characterized by downward displacement of variable severity of
the tricuspid valve into the right ventricle. The valve leaflets may be dysplastic,
and a variable portion of the proximal part of the right ventricle is in continuity
with the right atrium ('atrialized'), because of the abnormally positioned tricuspid
valve. The severity of this defect includes a spectrum ranging from severe disturbance
in fetal and neonatal life to virtually asymptomatic survival to adult life. Associated
extracardiac anomalies in the setting of chromosomal or mendelian disorders occur
in about 20% of patients with Ebstein anomaly. Nonsyndromic Ebstein anomaly can occur
as a sporadic or a familial defect (summary by Digilio et al., 2011).;