Transcatheter palliation with pulmonary artery flow restrictors in neonates with congenital heart disease: feasibility, outcomes, and comparison with a historical hybrid Stage 1 cohort
Authors: Sperotto Francesca , Lang Nora , Nathan Meena , Kaza Aditya , Hoganson David M , Valencia Eleonore , Allan Catherine K , Da Cruz Eduardo M , Del Nido Pedro J , Emani Sitaram M , Baird Christopher , Maschietto Nicola 
Published: May 2023

AbstractBackgroundNeonates with complex congenital heart disease (CHD) and pulmonary overcirculation have been historically treated surgically. However, sub-cohorts of patients may benefit from less invasive procedures. Transcatheter palliation with pulmonary flow restrictors (PFRs) may represent a compelling alternative, but data are limited.MethodsWe present our experience of palliation with PFRs in neonates with CHD and pulmonary overcirculation, including procedural feasibility, technical details, and patient-level 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 all-cause mortality risk at 6 months.ResultsFrom 2021 to 2023, 17 patients (median age 4 days, interquartile range [IQR] 2-8); median weight 2.51 kilograms [IQR 2.09-3.26]) underwent a PFR procedure; 15 (88%) had SV physiology; 15 (88%) were considered high-risk surgical candidates. All the procedures were technically successful. At a median follow-up of 5.3 months (IQR 1.9-9.6), 13 patients (76%) were either successfully bridged to surgery (n=10, 59%) or are awaiting surgery (n=3, 17%). Patients underwent the target surgery after a median of 2.6 months (IQR 1.2-3.4) from the PFR procedure (median weight 4.6 kilograms [IQR 3.2-5.4]). Their pulmonary arteries were found to have grown adequately for age. All PFR devices were easily removed without the 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, presence of intact atrial septum or severely restrictive patent foramen ovale, and presence of left ventricle to coronary fistulae), the PFR procedure was associated with a significantly lower all-cause 6-month mortality risk (adjusted Hazard Ratio=0.30 [95% CI 0.10- 0.93]).ConclusionsTranscatheter 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.Clinical perspectivesWhat is new?Transcatheter PFR palliation in high-risk neonates with congenital heart disease is feasible, safe, and effective in reducing pulmonary blood flow and allow for clinical stabilization and growing.PFR devices can be easily removed both at cardiac catheterization or surgery with no need for pulmonary arterioplasty, and pulmonary artery grow adequately over time.Compared to a historical cohort of high-risk single ventricle neonates palliated with a hybrid Stage-1, after adjustment for main confounding, the PFR palliation was shown to be associated with a significantly lower 6-month all-cause mortality risk.What are the clinical implications?Transcatheter PFR palliation in high-risk neonates may represent an effective alternative strategy to bridge such high-risk neonates to surgical palliation, complete repair, or transplant while avoiding a surgical procedure and allowing for clinical stabilization and somatic growth.