Prenatal echocardiographic predictors that increase the risk of urgent Ballon Atrial Septostomy (BAS) after birth in patients with Dextro-Transposition of the Great Arteries- Retrospective Study from Tertiary Center Lodz- Poland ICZMP (2014-2024)

OBJECTIVE: Dextro-transposition of the great arteries (d-TGA) is a critical congenital heart disease (CHD) requiring prompt postnatal intervention, primarily: a line for Prostin infusion, hospitalization in an Intensive Care Unit, and in some cases, Balloon Atrial Septostomy (BAS) as a rescue procedure before planned Arterial Switch Operation (ASO). In this part, we focus on prenatal prediction of postnatal BAS. MATERIALS AND METHODS: This retrospective study was conducted at the Department of Prenatal Cardiology, Polish Mother's Memorial Hospital in Lodz, covering the years 2014-2024. From a total of 112 prenatally diagnosed d-TGA cases, 70 fetuses (46 with isolated d-TGA and 24 with d-TGA and VSD) met the inclusion criteria; follow-up of four pregnancies ended up in other hospitals, so the final series was 66 cases. Statistical analyses were performed using Statistica software. RESULTS: Out of 66 analyzed cases, 32 newborns (48%) required postnatal BAS, with 87.5% of these procedures performed within the first 24-48 hours of life. Prenatal echocardiography correctly predicted the postnatal management pathway in 90.9% of cases (60/66), identifying all 26 neonates requiring urgent balloon atrial septostomy (100% positive predictive value), while 6 neonates in the planned group required unexpected postnatal septostomy. We noted that the 18% (n=6) of cases not identified prenatally occurred when the last scan was performed > 14 days before birth, suggesting that the time interval significantly impacts the reliability of late-gestation FO assessment. The study identified 10 prenatal "red flags," including FO size < 3 mm, bi-directional FO flow, and pulmonary vein velocity ≥ 45 cm/s and other features, as high-reliability indicators for urgent postnatal intervention. CONCLUSION: Prenatal functional assessment of the foramen ovale in the late third trimester was highly effective in predicting the need for postnatal urgent BAS in d-TGA cases. The accuracy of these "red flags" was significantly higher when the last fetal echocardiogram was performed within 14 days to delivery.