Abstract 14032: Transcatheter Palliation With Pulmonary Artery Flow Restrictors in Neonates With Congenital Heart Disease: Feasibility, Outcomes, and Comparison With a Historical Hybrid Stage 1 Cohort

Abstract

Introduction: Neonates with complex congenital heart disease (CHD) and pulmonary overcirculation have been historically treated surgically. However, sub-cohorts may benefit from less invasive procedures. Data on transcatheter palliation are limited to case reports. Hypothesis: Transcatheter palliation with pulmonary flow restrictors (PFR) may represent an effective palliation strategy in neonates with CHD, especially those at high surgical risk. Methods: We present our experience of PFR palliation in neonates with CHD, including procedural feasibility, technical details, and outcomes. We then compared our sub-cohort of high-risk single ventricle (SV) neonates palliated with PFRs with a historical cohort of high-risk SV neonates palliated with a hybrid Stage 1. Cox regression was used to evaluate the association between palliation strategy and mortality at 6 months. Results: From 2021 to 2023, 17 neonates (median age 4 d [IQR 2-8]; median weight 2.5 kg [IQR 2.1-3.3]) underwent a PFR procedure; 15 (88%) had SV physiology, 15 (88%) were high-risk surgical candidates. All procedures were technically successful. At a median follow-up of 5.2 mo (IQR 2.7-9.9), 13 patients (76%) were either successfully bridged to surgery (n=12, 71%) or are awaiting surgery (n=1, 6%). Patients underwent target surgery at a median of 2.5 mo (IQR 1.1-3.4) since the PFR procedure (median weight 4.6 kg [IQR 3.3-5.6]). Pulmonary arteries were found to have grown adequately for age. All PFR devices were easily removed with no need for arterioplasty. The all-cause mortality rate before target surgery was 24% (n=4). Compared to a historical cohort of high-risk SV neonates palliated with a hybrid Stage 1 (n=23), after adjustment for main confounding (age, weight, intact atrial septum/severely restrictive foramen ovale or left ventricle to coronary fistulae), the PFR procedure was associated with a significantly lower all-cause 6-month mortality risk (adjHR=0.30 [95% CI 0.10-0.93]). Conclusions: Transcatheter PFR palliation in high-risk neonates with CHD is feasible, safe, and may represent an effective alternative strategy to bridge such high-risk neonates to surgical palliation, complete repair, or transplant while allowing for clinical stabilization and somatic growth.