A Novel Restorative Pulmonary Valved Conduit: Early Outcomes of Two Clinical Trials

Division Chief of Pediatric Cardiothoracic Surgery at UPMC Children’s Hospital of Pittsburgh, Victor O. Morell, MD, co-authored a new paper presenting results from a multicenter clinical trial that examined the first use of a biorestorative valved conduit (Xeltis pulmonary valve – XPV) in children.

Valved conduits are often used in pediatric cardiothoracic surgical procedures, such as in the reconstruction of the right ventricular outflow tract (RVOT), which is “one of the most common procedures in pediatric heart surgery,”¹ as a consequence of numerous congenital heart lesions (e.g., tetralogy of Fallot, ventricular septal defect). There has been a continuous search for a valved conduit that offers a truly restorative approach to rebuilding cardiac tissue within patients after implantation, one that eliminates the need for repeat interventions as the patient grows.

This study¹ reports on the results of two clinical trials that test the first uses of XPV valves in children. It should be noted that the original valve used in the first clinical trial, XPV-1, was redesigned into XPV-2 after five of the patients experienced pulmonary valve regurgitation with the first version.

Group 1 included 12 children ages 2 to 12 years old who received an implantation of XPV-1. Five children had a 16 mm diameter conduit implanted, while the seven other children received an 18 mm diameter conduit. Group 2 included six children ages 3 to 9 years old who received an implantation of XPV-2. Each participant in group 2 received an 18 mm diameter conduit.

Dr. Morell and his colleagues compared the performance of the valves within both groups after 12 months of follow-up care. Five of the patients in group 1 experienced pulmonary valve regurgitation, while three others exhibited “residual gradients of > 40 mmHg due to kinking of the conduit and peripheral stenosis of the branch pulmonary arteries.”¹ After the redesign of the original XPV model, only one patient from group 2 experienced pulmonary valve regurgitation. One patient from group 2 did require reoperation, as they experienced stenosis and the conduit needed replaced.

Overall, 17 of the 18 patients involved in the clinical trials did not need re-intervention. Results from this study demonstrate the benefits of the XPV conduit design and how it improves the treatment standard for children who undergo right ventricular outflow tract reconstruction. An U.S. Food and Drug Administration-approved clinical trial has been designed to assess longer term follow-up of the current XPV-2 conduit design.

Reference

1 Morales DL, Herrington C, Bacha EA, et al. A Novel Restorative Pulmonary Valved Conduit: Early Outcomes of Two Clinical Trials. Front Cardiovasc Med. 2021; 7: 583360. Published 2021 Mar 4. doi:10.3389/fcvm.2020.583360.