# Cylinder Bicuspid Pulmonary Valve Reconstruction Using Equine Pericardium: A Novel Technique for Right Ventricular Outflow Tract Repair

## TL;DR

A new surgical technique using equine pericardium to create a bicuspid pulmonary valve shows promise in reducing heart obstruction in children.

## Contribution

A novel technique using equine pericardium for cylinder bicuspid pulmonary valve reconstruction is introduced.

## Key findings

- The median peak RVOT pressure gradient decreased significantly postoperatively.
- Mild pulmonary regurgitation was observed in only one patient.
- No postoperative mortality was recorded in the short-term follow-up.

## Abstract

Background: Right ventricular outflow tract (RVOT) reconstruction is frequently performed for pediatric patients with pulmonary valve anomalies, yet optimal techniques remain debated. The equine pericardium offers a promising substrate for pulmonary valve reconstruction but has been understudied in pulmonary valve reconstruction. This study evaluated a novel technique using the equine pericardium to create a cylinder bicuspid pulmonary valve for RVOT reconstruction. Methods: In this retrospective cohort study, 17 pediatric patients (median age: 10 months; 53% male) underwent RVOT reconstruction with equine pericardium between 2023 and 2024. The valve was fashioned from a patch of equine pericardium into a cylinder to create a functionally bicuspid valve. The height of the cylinder ranged from 1.5–2 cm. The diameter was measured around a Hegar dilator corresponding to a valve size z-score of +3. The outcomes included the degree of postoperative pulmonary regurgitation, RVOT pressure gradients, postoperative complications, and reinterventions. Results: Postoperatively, the median peak RVOT pressure gradient decreased significantly from 70 mmHg (IQR: 65–90) to 25 mmHg (IQR: 20–40; p < 0.001). Mild pulmonary regurgitation persisted in one patient (5.9%). Five patients had mild right ventricular dysfunction (29.41%). At a median 3-month follow-up (IQR: 1–8), 17.7% (n = 3) underwent cardiac catheterization. There was no postoperative mortality. Conclusions: Cylinder bicuspid pulmonary valve reconstruction using the equine pericardium effectively reduces RVOT obstruction while maintaining pulmonary valve competence and demonstrates acceptable short-term safety. Having a competent pulmonary valve after repairing the hypoplastic pulmonary valve annulus is very promising; however, the small cohort and limited follow-up preclude definitive conclusions about long-term durability. Larger prospective studies with longer follow-up periods are needed to validate this technique for RVOT reconstruction.