(62) Burden of Patent Ductus Arteriosus Shunt Exposure and Its Impact on Adverse Cardiopulmonary Disease in Patients Undergoing Transcatheter Closure

Background: Transcatheter patent ductus arteriosus (PDA) closure is a contemporary approach in preterm infants. Post-transcatheter cardiorespiratory syndrome (PTCS) occurs in about 25% of small neonates, but the impact of PDA exposure on the risk of PTCS remains unknown. We hypothesized that the burden of PDA shunt is inversely associated with risk for PTCS. Prolonged shunt exposure may remodel immature pulmonary vasculature and alter left ventricular hemodynamics, leading to greater stability after catheterization.

Objectives: To evaluate the burden of PDA shunt and its association with the risk of developing PTCS in patients undergoing transcatheter PDA closure.

Design/Methods: A retrospective cohort study of premature infants who underwent transcatheter PDA closure at ≤ 2kg at the time of intervention was conducted. All targeted neonatal echocardiograms (TNE) preceding the PDA closure were analyzed, and cumulative PDA shunt exposure was calculated by adding-up the PDA scores and days of exposure until definitive closure. Patients with and without PTCS were compared using Student t-test and Mann-Whitney as appropriate for continuous variables. Categorical variables were analyzed using χ² or Fisher’s exact test and logistic regression was conducted.

Results: A total of 74 infants were included with mean gestational age and birth weight of 25.2 ± 1.9 weeks and 697 [IQR 600, 943] grams, respectively. In total, 81.1% of infants received milrinone prophylaxis, as per the standardized unit protocol, of whom only 18.9% developed PTCS (Table 1). Infants developing PTCS had greater respiratory needs patients and were less likely to be >1500g. A total of 646 pre-closure TNEs were included; overall cumulative PDA exposure and days with at least moderate shunt volume did not correlate with PTCS development and individual components of post-transcatheter instability. Logistic regression showed that pre-closure respiratory severity score remained associated with the development of PTCS (p=0.002) when adjusted for age at intervention (p=0.069) and PDA burden (p=0.074).

Conclusions: In patients undergoing transcatheter PDA closure, burden of PDA shunt exposure was not associated with lower risk of PTCS. This may relate to the homogeneity in timing of the closure, high-risk nature of our cohort, and frequent use of milrinone prophylaxis. Future studies assessing PDA burden should be conducted, including milrinone-naïve populations, to further evaluate the impact on post-catheter instability.