Immediate Therapeutic Outcomes and Medium-term Follow-up of Percutaneous Balloon Pulmonary Valvuloplasty in Infants with Pulmonary Valve Stenosis: A Single-center Retrospective Study

Background: Percutaneous balloon pulmonary valvuloplasty (PBPV) is the preferred therapy for pulmonary valve stenosis (PVS). This study retrospectively reviewed recent PBPV outcomes in infants with PVS. The aim of this study was to evaluate factors associated with immediate therapeutic outcomes and restenosis during medium-term follow-up. Methods: The study included 158 infants with PVS who underwent PBPV from January 2009 to July 2015. Demographic characteristics and patient records were reviewed, including detailed hospitalization parameters, hemodynamic data before and immediately after balloon dilation, cineangiograms, and echocardiograms before PBPV and at each follow-up. All procedures were performed by more than two experienced operators. Results: Immediately after balloon dilation, the pressure gradient across the pulmonary valve decreased from 73.09 ± 21.89 mmHg (range: 43-151 mmHg) to 24.49 ± 17.00 mmHg (range: 3-92 mmHg; P < 0.001) and the right ventricular systolic pressure decreased from 95.34 ± 23.44 mmHg (range: 60-174 mmHg) to 52.07 ± 18.89 mmHg (range: 22-134 mmHg; P < 0.001). Residual transvalvular pressure gradients of 67.31 ± 15.19 mmHg (range: 50-92 mmHg) were found in 8.2% of patients, indicating poor therapeutic effects; 6.4% of patients had variable-staged restenosis at follow-up and 3.8% underwent reintervention by balloon dilation or surgical repairs. Further analysis demonstrated that the balloon/annulus ratio showed statistically significant differences (P < 0.05) among groups with different therapeutic effects and between the restenosis and no-stenosis groups. Binary logistic regression analysis further revealed that higher balloon/annulus ratio (odds ratio: 0.005, 95% confidence interval: 0-0.39) was an independent protective factor for restenosis. The rate of severe complications was 1.9%. Conclusions: PBPV is a definitive therapy for infants with PVS based on its effectiveness, feasibility, and safety. Restenosis upon medium-term follow-up is relatively rare. Key words: Balloon Valvuloplasty; Cardiac Catheterization; Infants; Pulmonary Valve Stenosis