Follow-Up of Neonatally Diagnosed Atrial Septal Defects and Patent Foramen Ovale at Preschool Age

BACKGROUND: Interatrial communications (IACs) are common in newborns. While most close spontaneously, some persist as patency of the oval foramen (PFO) or atrial septum defects (ASDs). While PFOs are mostly benign, ASDs may require surveillance and treatment. Distinguish ASDs from PFOs in newborns, and deciding who requires follow-up, can be challenging. We previously developed an algorithm to improve classification of IACs in newborns. This study aimed to evaluate the patency at preschool-age of neonatal IACs classified using the algorithm.

METHODS: We reexamined children from the Copenhagen Baby Heart Study who underwent neonatal transthoracic echocardiography (TTE). Neonatal TTEs were previously classified into PFO and ASD subtypes using our algorithm. ASDs were distinguished from PFOs by defect size ≥4mm, abnormal location, or multiple communications. For this study, we reexamined >200 children with each type of neonatal IAC and >200 without a neonatally identified IAC. Patent IACs at follow-up were reclassified using the algorithm.

RESULTS: We reexamined 1,099 children (median age 5.2 [interquartile range 4.9-5.5] years, 53% female): 290 with neonatal ASD, 608 with neonatal PFO, and 201 without neonatal IAC. At follow-up, spontaneous closure, i.e. no detectable residual shunt by color Doppler, was observed in 81.7% of children with neonatal ASD (n=237) and in 89.9% of children with neonatal PFO (n=546). Among children without neonatally identified IACs, the follow-up TTE revealed an IAC in 5.0% (n=10). Children with a neonatal ASD were eight times more likely to have a ASD at follow-up than children with a neonatal PFO or no neonatal IAC (adjusted odds ratio 8.2, 95% confidence interval 3.6-18.7, P<0.0001). Four children, all with neonatal ASDs, required surgical ASD closure.

CONCLUSIONS: Spontaneous closure rates of all neonatal IAC types were high. Children classified by the algorithm as having neonatal ASD had a significantly higher risk of persistent ASD, supporting its value in identifying newborns who may benefit from follow-up, recommending targeted follow-up of neonatal ASDs only.