International Multicenter Outcomes of Transcatheter Pulmonary Flow Restrictors in Congenital and Acquired Heart Disease

This is a multicenter, international, non-randomized, non-interventional, observational post-marketing clinical follow-up study with retrospective and prospective data collection, designed to evaluate the feasibility, safety, and efficacy of off-label implantation of microvascular plug (MVP)-based pulmonary flow restrictors (PFRs) in patients with congenital and acquired heart disease.

• Transcatheter pulmonary flow restriction (Device), also known as Percutaneous pulmonary flow restriction, Endovascular pulmonary flow restriction: Transcatheter implantation of a microvascular plug (MVP)-based pulmonary flow restrictor (PFR) in a single or bilateral pulmonary artery (PA) branch(es).

Primary outcomes

• Net clinical success [From date of device implant until the date of surgical device removal, assessed up to 24 months]: Composite non-hierarchical net clinical success, evaluated at the time of surgical PFR removal (either as a standalone procedure or during target surgery), and defined by meeting the following three criteria: 1) technical success (successful implantation and retention* of the MVP device in each branch PA), 2) clinical success (evidence of PBF restriction** at PFR removal), and 3) safety success (no major adverse device-related events (MADREs).

Secondary outcomes

• Technical implantation success [From date of device implant until hospital discharge, assessed up to 6 weeks]: Technical success of PFR implantation (device successfully delivered, deployed, and retained in each branch PA) at hospital discharge after the index procedure.
• Immediate flow restriction success [From device implant to procedure conclusion]: Immediate flow restriction success of MVP-based PFRs, defined as technical success and evidence of pulmonary blood flow (BPF) restriction, at procedure conclusion (Evidence of PBF restriction at procedure conclusion was defined as a minimal drop in oxygen saturation on arterial blood gas by 10% at the same level of FiO2 compared to preoperative levels, a systolic-diastolic Doppler-pattern across the PFRs with a minimum peak Doppler gradient of 40 mmHg (Vmax=3.2 m/s) on per-procedural ultrasound assessment, and, when performed, a reduction in the baseline QP/QS mismatch by 50%).
• Safety success [From date of device implant until the date of surgical device removal, assessed up to 24 months]: Safety success (freedom from MADREs*, vascular-, or procedure-related SAEs**) at the time of device removal. The severity of MADRE and SAE will be classified using a validated 1-to-5 scale, ranging from none to catastrophic. *MADREs include device-related vascular erosion, vascular aneurysm/pseudoaneurysm, bronchial compression, device collapse, migration, embolization, thrombosis, fracture, infection, endocarditis, resulting in unplanned or anticipated device removal, or redo-intervention (surgical or catheter-based) **SAEs encompassed device- vascular- or procedure-related adverse events resulting in death, life-threatening situations, hospitalization, disability, or major surgical intervention.
• All cause mortality [From date of device implant until the date of surgical device removal, assessed up to 24 months]: All-cause mortality rate at the time of device removal.

Other outcomes

• Freedom from unplanned pulmonary artery (PA) reintervention [From date of device implant until the date of surgical device removal, assessed up to 24 months]: Freedom from unplanned PA reintervention (surgical or catheter-based) until surgical device removal
• Freedom from unplanned pulmonary artery intervention post-device removal [From date of surgical device removal through 24 months after removal]: Freedom from unplanned PA intervention at 24 months following surgical device removal (such as angioplasty or stenting for residual stenosis or deformity at the former device site).

Sex: All, ages: any to 3 Years

Inclusion Criteria:

* Pediatric patients (≤3 years) with any congenital or acquired heart disease, regardless of gender, ethnicity, or geographic location, who underwent transcatheter insertion of the MVP-based PFR device in single or bilateral PA branches between January 2019 and January 2028.
* Informed consent obtained from parents or legal guardians.

Exclusion Criteria:

* Study device implanted in other locations: modified BT shunt, arterial duct, stented arterial duct, Sano conduit, and central shunt.

• Raymond N. Haddad, MD, MHSc, PhDc, Principal investigator, Marie Lannelongue Hospital, INSERM, UMR-S1358, UP-Saclay