Objective:

Assess whether fetal echocardiographic findings can predict neonatal hypoxia or the need for urgent balloon atrial septostomy (BAS) in infants with prenatally diagnosed dextro-transposition of the great arteries with an intact ventricular septum (dTGA/IVS).

Approach:

• Study design and participants: Prospective, observational, multicenter study of 132 mother-infant pairs enrolled at 23 North American institutions from 2019 to 2022.
• Measurements and outcomes: Researchers assessed third-trimester fetal echocardiograms, including foramen ovale-to-total septal length ratio, septum primum angle, atrial septal excursion ratio, and atrial septal hypermobility. Neonatal hypoxia was defined as PaO2 below 30 mmHg or SpO2 be…

Key Findings:

• Neonatal hypoxia occurred in 38% of infants; approximately 61% of those infants underwent BAS, and nearly 88% of those procedures were considered urgent.
• Among infants without hypoxia, 51% underwent BAS; 88% of those procedures were considered urgent.
• Fetal echocardiographic findings did not reliably identify which infants would develop hypoxia or remain stable after birth, and could both miss and overestimate the need for BAS and urgent care.

Interpretation:

Study co-author Christopher Lindblade said the findings support high-risk delivery planning for every infant with prenatally diagnosed dTGA/IVS, including when fetal echocardiograms appear reassuring, because hypoxia and urgent BAS cannot be reliably predicted prenatally.

Limitations:

• The provided article context does not report additional study limitations.

Conclusion:

The article also describes a separate Phoenix Children’s study in which bedside interventional-team care was associated with shorter time to BAS: 1.1 hours, compared with 9.3 hours after postnatal diagnosis and 4.5 hours with rapid transport. The article reports lower peak lactate and less severe acidemia in the bedside-team group, but no reduction in hospital stay.