Background: Coarctation of the Aorta (CoA) occurs in 0.3 per 1000 live births and accounts for 6 - 8% of infants with congenital heart disease. Prenatal diagnosis of CoA is beneficial to guide optimal postnatal management. In 2014, the Connecticut Children’s Fetal Cardiology Team created the Antenatal Risk of Coarctation in Hartford (ARCH) clinical pathway that stratifies risk of ductal dependency in suspected prenatal CoA. Based on the degree of clinical suspicion, an assigned ARCH score provides guidelines on postnatal management including need for immediate prostaglandins after delivery, time to echocardiogram and invasive testing and procedures. This system aims to decrease provider variation and promote safe, effective, and consistent care. This study aims to evaluate the safety and efficacy of the ARCH scoring system in neonates with suspected CoA. 

Methods: A single center retrospective chart review was performed. Mothers carrying fetuses with suspected CoA between July 2004 and July 2021 evaluated at Connecticut Children’s Fetal Cardiology division were included. Participants from two eras were studied: pre-ARCH score versus post-ARCH score implementation. Neonates were further evaluated based on the presence or absence of critical CoA. Data including demographics, interventions, and outcomes were obtained. Statistical analysis was performed using chi square and Fisher’s exact test.

Results: Of the 108 maternal-infant dyads, 53 were delivered in the pre-ARCH era and 55 in the post-ARCH era. Critical coarctation was diagnosed in 33 neonates overall with 23 in the pre-ARCH era and 10 in the post-ARCH era.  Neonates with a critical CoA in the pre-ARCH era had a higher likelihood of being transferred from an outside hospital after birth compared to those in the post-ARCH era (56.5% vs 10.0%, P = 0.021).  There was no significant difference in NICU admissions, prostaglandin administration, intubation or inotropic use between pre and post ARCH groups (P <0.05). In patients without CoA, more echocardiograms were performed in the post-ARCH group than the pre-ARCH group (1.586 vs 2.133, P = 0.049).  Otherwise there was no significant difference resource utilization between eras in participants without CoA. Prenatal high risk categorization (ARCH 1 or 2) was highly associated with diagnosis of critical CoA (P= 0.003). 

Conclusion: The ARCH score is a safe, reliable prenatal risk stratification system that can help guide management of patients with critical CoA. Our study showed a reduction in postnatal transfer of care for neonates with critical CoA after ARCH score initiation. There was no significant increase in NICU admission or invasive procedures in patients without CoA after pathway implementation. However, there was an increase in the number of echocardiograms performed in these patients without CoA after pathway implementation. These results identify effective targets of modification to the pathway to reduce resource utilization without compromising safety.