Neonatal intracardiac thrombosis secondary to transplacental transfer of maternal antiphospholipid antibodies-a case report and review of the literature.

BACKGROUND

Maternal antiphospholipid immunoglobulin (Ig) G antibodies can cross the placenta, placing neonates at uncertain risk for thrombosis. There are no previous reports of neonatal intracardiac thrombosis (ICT) in the context of anticardiolipin antibodies (aCL).

KEY CLINICAL QUESTION

What were the clinical manifestations, management, and outcomes for a mother and her child with ICT secondary to presumed transplacental transfer of aCL?

CLINICAL APPROACH

A 2-week-old female presented with reduced feeding and was found to be poorly perfused with significant lactic acidosis. A mobile mass was noted near the left atrial appendage on the echocardiogram and confirmed on cardiac magnetic resonance imaging. Magnetic resonance imaging of the brain was normal, with no evidence of stroke. The aCL IgG titers returned highly positive for the infant (115.3 IgG phospholipid (GPL)-Unit [U]/mL) and mother (>160 GPL-U/mL; >99th percentile local reference is ≥20 GPL-U/mL). There were no other overt risk factors for thrombosis. The infant received 6 months of enoxaparin until aCL normalized. There remains a small calcified thrombus adherent to the left atrial wall. At 2 years old, the child remains healthy with no cardiac, neurologic, nor thrombotic sequelae.

CONCLUSION

This is the first report of neonatal ICT presumed secondary to maternal aCL. The outcome was favorable with anticoagulation management. Further research is needed in the area of transplacental antiphospholipid antibody transfer, identification of neonates at risk, and optimal clinical management.