Fetal Pulmonary Valvuloplasty in Fetuses with Right Ventricular Outflow Tract Obstructive Disease: Experience and Outcome of the First Five Cases in China.

The current study was to report our initial experiences of fetal pulmonary valvuloplasty (FPV) for fetuses with pulmonary atresia with intact ventricular septum (PA/IVS) and critical pulmonary stenosis (CPS), including case selection, technical feasibility, and the effects of FPV on utero and postnatal outcome. Two fetuses with PA/IVS and three fetuses with CPS were enrolled between September 2016 and April 2018. All fetuses were with concomitant severe right ventricular dysplasia and growth arrest. Parameters of right cardiac development and hemodynamics, including tricuspid/mitral annulus ratio (TV/MV), right ventricle/left ventricle long-axis ratio (RV/LV), tricuspid valve inflow duration/cardiac cycle ratio (TVI/CC), degree of tricuspid regurgitation (TR), and blood flow direction of arterial duct and ductus venosus, were evaluated using echocardiogram. FPV was performed trans-abdominally under ultrasound guidance. Echocardiogram was performed post-FPV and every 2-4 weeks thereafter until delivery. The median gestational age at the time of FPV was 28 weeks. From technical perspective, pulmonary balloon valvuloplasty was successfully performed and the opening of pulmonary valve was improved in all fetuses in 2-4 weeks. However, progressive restenosis was observed in four fetuses with gestation advancing, and re-atresia occurred in two PA/IVS fetuses at 36th and 37th weeks' gestation, respectively. The growth trajectories of TV/MV, RV/LV, and TVI/CC were improved in the 1st week after FPV and then slowed down along with pulmonary valve restenosis. All fetuses were born alive and underwent postnatal interventions, including pulmonary balloon valvuloplasty in three fetuses and surgical procedures in two fetuses. During follow-up, three fetuses turned to be biventricular, one became one and a half ventricular at 1-year old, and one died of neonatal infection. Although pulmonary valve restenosis might occur as gestation advancing, FPV seems to be a safe and feasible procedure to improve the growth trajectories of right heart for fetuses with PA/IVS and CPS.