Background: Distances between delivery centers and cardiac services can make the care of fetuses with cardiac disease(CD) at risk of acute cardiorespiratory instability(ACRI) at birth a challenge. In 2013 we implemented a fetal echocardiography(FE)-based algorithm targeting fetuses considered high-risk for ACRI at <2 hours of birth for Caesarian section(CS) delivery in our pediatric cardiac operating room(PCOR) of our children's hospital. We examine the experience and outcomes of affected newborns. Methods: We reviewed maternal and postnatal medical records of all fetuses with CD at high-risk for ACRI encountered January 2013-March 2022. Secondary analysis was performed including all fetuses with diagnoses of d-transposition of the great arteries/intact ventricular septum(d-TGA/IVS) and hypoplastic left heart syndrome(HLHS) encountered over the study period. Results: Forty fetuses were considered high-risk for ACRI: 15 d-TGA/IVS and 7 HLHS with restrictive atrial septum(RAS), 4 absent pulmonary valve syndrome, 3 obstructed anomalous pulmonary veins, 2 severe Ebstein anomaly, 2 thoracic/intracardiac tumors and 7 others. PCOR delivery occurred for 33 but not for 7 (5 d-TGA/IVS, 2 HLHS with RAS). For high-risk cases, FE had a positive predictive value of 50% for intervention/ECMO/death at <2 hours and 70% at <24 hours. Of "low-risk" cases, 6/46 with d-TGA/IVS and 0/45 with HLHS required intervention at <2 hours. FE predicted intervention/ECMO/death at <2hours with a sensitivity of 67%, specificity 93%, and positive and negative predictive values of 87% and 87%, respectively, for d-TGA/IVS, and 100%, 95%, 71%, and 100% for HLHS, respectively. Conclusions: FE predicts need for urgent intervention in majority with d-TGA/IVS and HLHS, and in half of the entire spectrum of high-risk CD.

The authors have declared no competing interest.

Drs Moray and Mugaba had salaries supported by the Stollery Children's Hospital Foundation and the Department of Pediatrics

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This study was fully approved by the University of Alberta Research Ethics Board. The ethics proposal number is Pro00077901 and this has been approved to February of 2024.

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