Ebstein's anomaly is a rare heart defect that's present at birth (congenital). In Ebstein's anomaly, your tricuspid valve — the valve between the two right heart chambers (right atrium and right ventricle) — doesn't work properly. The tricuspid valve sits lower than normal in the right ventricle, and the tricuspid valve's leaflets are abnormally formed.
Blood may leak back through the valve, making your heart work less efficiently. Ebstein's anomaly may also lead to enlargement of the heart or heart failure.
If you have no signs or symptoms associated with Ebstein's anomaly, careful monitoring of your heart may be all that's necessary. If signs and symptoms bother you, or if the heart is enlarging or becoming weaker, treatment for Ebstein's anomaly may be necessary. Treatment options include medications and surgery.
Ebstein's anomaly care at Mayo Clinic