Modified underlying cardiac disease severity in twin-twin transfusion syndrome

Area of Science:

• Cardiology
• Fetal Medicine
• Neonatology

Background:

• Monochorionic-diamniotic twins share a placenta, increasing risks of unequal blood distribution.
• Twin-twin transfusion syndrome (TTTS) can cause significant intravascular volume discrepancies between fetuses.
• Tricuspid regurgitation (TR) is a potential cardiac complication in affected fetuses.

Observation:

• One twin (recipient) presented with Ebstein anomaly and mild TR.
• The other twin (donor) exhibited tricuspid valve dysplasia with moderate TR.
• Postnatal assessment revealed decreased TR in the recipient and increased TR in the donor.

Findings:

• Intravascular volume shifts due to TTTS influenced the observed severity of fetal TR.
• The recipient twin's intrinsic TR severity may have been underestimated.
• The donor twin's intrinsic TR severity may have been overestimated.

Implications:

• Clinical assessment of fetal TR in TTTS requires careful consideration of volume status.
• Accurate evaluation of intrinsic valvular disease severity is crucial for appropriate management.
• This case highlights the dynamic nature of fetal cardiac conditions influenced by placental sharing.