To present the short-term clinical trial outcome of the Med-Zenith pulmonary valve in treating postoperative pulmonary regurgitation in children with congenital heart disease.

Between January 2021 and March 2023, prospective screening of children with moderate to severe pulmonary regurgitation in Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University. The anatomy of right ventricular outflow tract, left and right ventricular volumes and pulmonary regurgitation fraction were evaluated by cardiac tomography angiography and cardiac magnetic resonance imaging (MRI). For patients who met the inclusion criteria, Med-Zenith pulmonary valve was implanted. During acute and short-term follow-up, the function of the Med-Zenith pulmonary valve, ventricular volume and complications were assessed. Inclusion criteria: ①Age ≥ 10 years or weight ≥ 25 kg. ②New York Heart Association (NYHA) functional class Ⅱ or above, accompanied by moderate to severe pulmonary regurgitation measured by echocardiography or a pulmonary regurgitation fraction ≥30% measured by magnetic resonance imaging.

A total of 13 patients with severe pulmonary regurgitation postoperative underwent successful implantation of Med-Zenith pulmonary valve. Among these patients, boys accounted for 61.5% (8/13). Mean age and mean weight at implantation were (14.5±2.1) years and (50.3±7.9) kg, respectively. After a median follow-up of 12.0 (12.0,24.0) months, all patients were clinically stable. All patients showed trivial or mild pulmonary regurgitation by echocardiography, and no paravalvular leakage was observed. Mean peak systolic pulmonary artery gradient was not significantly different from that before operation [(15.7±8.3) mmHg vs. (13.8±5.6) mmHg, P=0.429]. Mean right ventricular end-diastolic volume index, mean right ventricular end-systolic volume index and mean pulmonary artery regurgitation fraction by MRI were significantly decreased [(129.7±24.1) ml/m² vs. (197.7±18.9) ml/m², P<0.001; (129.7±24.1) ml/m² vs.(197.7±18.9) ml/m²,P<0.001;(6.4±6.0) % vs. (54.8±8.3) %, P<0.001]. Mean left ventricular end-diastolic volume index, the left ventricular end-systolic volume index was significantly increased [ (94.8±14.2 ml/m² vs. (88.4±9.6) ml/m², P=0.046; (49.2±18.5) ml/m² vs. (39.7±9.2) ml/m², P=0.025]. X-ray examination showed no fracture, displacement or deformation of the device. There was no serious device-related adverse event.

Med-Zenith pulmonary valve is safe and easy to treat pulmonary artery regurgitation after surgery in children with congenital heart disease. At a median follow-up of 1 year, 100% of the patients had mild or less valvular regurgitation, and no paravalvular leak was observed. The cadiac function of patients improved and the left and right ventricular volume indexes also significantly improved.