ObjectivesTo analyze the prevalence and severity of fetal aortic regurgitation (AR) after undergoing fetal aortic valvuloplasty (FAV) and to evaluate its effects on fetal circulation and left ventricular (LV) growth. MethodsThis was a retrospective review of all fetuses with critical aortic stenosis who underwent FAV at our center between 2010 and 2024 for whom postnatal echocardiograms were available in digital format. Fetal and postnatal echocardiographic examinations were analyzed for ventricular and valvular dimensions and characteristics, and Z-scores were calculated for middle cerebral artery (MCA) pulsatility index (PI), umbilical artery (UA) PI and cerebroplacental ratio. AR severity was classified into no/mild AR or significant (moderate/severe) AR. The balloon-to-aortic valve ratio (BVR) was calculated as the ratio between the maximum actual balloon diameter and the aortic valve (AV) annulus diameter. The primary endpoints of this study were the prevalence, severity and risk factors for fetal AR following successful FAV. ResultsNinety-nine fetuses who underwent successful FAV were included. Immediate post-FAV echocardiograms showed that 87% of fetuses developed some degree of AR, including 45% of all fetuses with significant AR. BVR was significantly higher in fetuses with significant AR compared to those with no/mild AR (mean, 1.09 (95% CI, 1.06-1.12) vs 1.02 (95% CI, 0.99-1.04); P < 0.001). In a subgroup of 66/99 fetuses with available postnatal echocardiograms, the prevalence of AR decreased significantly from 86% before birth to 58% after birth (P < 0.001), with the proportion of fetuses with significant AR reducing from 47% before birth to 17% after birth (P < 0.001). In the overall cohort of fetuses, AV maximum velocity (Vmax) increased significantly from post-FAV to after birth (mean, 1.93 (95% CI, 1.75-2.11) m/s vs 3.21 (95% CI, 2.89-3.55) m/s; P < 0.001), regardless of AR severity, but Vmax after birth was lower in the significant-AR group compared with the no/mild-AR group (mean, 2.85 m/s vs 3.55 m/s; P = 0.020). Fetuses with significant AR exhibited higher relative LV length increases from immediately post-FAV to after birth than did those with no/mild AR (25% (95% CI, 16-33%) vs 14% (95% CI, 6-21%); P = 0.044), although there was no significant difference in mean LV length Z-score after birth between the two groups. FAV led to significant short-term increases in MCA-PI and UA-PI Z-scores, with greater increases observed in fetuses with significant AR. ConclusionsFAV is associated with a high prevalence of fetal AR, which lessens in severity over the course of gestation. Significant fetal AR had the largest association with greater BVR and had significant impact on fetal hemodynamics. (c) 2025 The Author(s). Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Background: In critical LVOT obstruction, there are few prognostic scores for decision making between univentricular and biventricular repair: Rhodes-, Discriminant-, CHSS1- and CHSS2-Score. In the underlying studies the usual type of biventricular repair was either surgical or balloon valvuloplasty. The Ross–Konno operation changes the LVOT substantially and so some of the scores' parameters. The purpose of this study is to examine if these scores are still applicable if a Ross–Konno procedure is used.

Objectives To review our experience with fetal aortic valvuloplasty (FAV) in fetuses with critical aortic stenosis (CAS) and evolving hypoplastic left heart syndrome (eHLHS), including short- and medium-term postnatal outcome, and to refine selection criteria for FAV by identifying preprocedural predictors of biventricular (BV) outcome. Methods This was a retrospective review of all fetuses with CAS and eHLHS undergoing FAV at our center between December 2001 and September 2020. Echocardiograms and patient charts were analyzed for pre-FAV ventricular and valvular dimensions and hemodynamics and for postnatal procedures and outcomes. The primary endpoints were type of circulation 28 days after birth and at 1 year of age. Classification and regression-tree analysis was performed to investigate the predictive capacity of pre-FAV parameters for BV circulation at 1 year of age. Results During the study period, 103 fetuses underwent 125 FAVs at our center, of which 87.4% had a technically successful procedure. Technical success per fetus was higher in the more recent period (from 2014) than in the earlier period (96.2% (51/53) vs 78.0% (39/50); P = 0.0068). Eighty fetuses were liveborn after successful intervention and received further treatment. BV outcome at 1 year of age was achieved in 55% of liveborn patients in our cohort after successful FAV, which is significantly higher than the BV-outcome rate (23.7%) in a previously published natural history cohort fulfilling the same criteria for eHLHS (P = 0.0015). Decision-tree analysis based on the ratio of right to left ventricular (RV/LV) length combined with LV pressure (mitral valve regurgitation maximum velocity (MR-Vmax)) had a sensitivity of 96.97% and a specificity of 94.44% for predicting BV outcome without signs of pulmonary arterial hypertension at 1 year of age. The highest probability for a BV outcome was reached for fetuses with a pre-FAV RV/LV length ratio of < 1.094 (96.4%) and for those fetuses with a RV/LV length ratio >= 1.094 to < 1.135 combined with a MR-Vmax of >= 3.14 m/s (100%). Conclusions FAV could be performed with high success rates and an acceptable risk with improving results after a learning curve. Pre-FAV RV/LV length ratio combined with LV pressure estimates were able to predict a successful BV outcome at 1 year of age with high sensitivity and specificity. (c) 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.