Intrauterine Valvuloplasty in Severe Aortic Stenosis—A Ten Years Single Center Experience

Abstract

Objective: To assess the course and outcome of fetal aortic valvuloplasty (FAV) in fetuses with severe aortic stenosis (SAS) in a single center. Methods: All fetuses with a prenatal diagnosis of SAS with subsequent FAV were retrospectively collected in one tertiary center for fetal medicine over a period of 10 years. In the study, period fetuses with SAS were considered suitable for FAV in the presence of markedly elevated left ventricular pressures (maximum velocity of mitral regurgitation (MR Vmax) >250 cm/s and/or maximum velocity of aortic stenosis (AS Vmax) >250 cm/s), retrograde flow in the transverse aortic arch and a left ventricular length Z-score >−1. Results: In the study period 29 fetuses with AS were treated with 38 FAV. If reinterventions are included 82.7% of fetuses received a technically successful FAV. Procedure related death occurred in three (10.3%) cases, spontaneous fetal death in 2 (6.9%), and termination of pregnancy was performed in 3 cases (10.3%). Among the 21 live births (72.4%), four died in infancy. Among the remaining survivors, 8/17 (47.1%) had a biventricular outcome at the age of one year, 8/17 (47.1%) were univentricular and one infant (5.9%) is biventricular at the age of eight months. Fetuses with biventricular outcome had significantly greater left ventricular (LV) length Z-scores (p = 0.031), and lower tricuspid to mitral valve (TV/MV) ratios (p = 0.003). Conclusions: FAV has a high technical success rate and a low rate of procedure related mortality if performed in experienced hands. The success rate of biventricular circulation at the age of one year is moderate and seems to depend rather on the center’s experience and postnatal surgical strategies than solely on prenatal selection criteria. In the absence of randomized controlled trials, FAV remains an experimental intervention.

Fetal aortic valvuloplasty as the first step in a complex therapeutic strategy

“…Regarding the fetal cardiac procedures, our results are similar to other studies reporting a similar number of interventions 20,21,27 . There is a consensus that fetal therapies should be conducted in Fetal Treatment Centers equipped with specific resources, expertise, credentialing and infrastructure 28,29 .…”

“…smaller series have found similar results. 18,20,21 In our center, 39% (6/13) of patients had a biventricular circulation at 28 days of life after a technically successful FAV. Our series included a small number of patients over an 18-year period, likely reflecting suboptimal local prenatal diagnosis rates and frequent delays in referrals.…”

“…Regarding the fetal cardiac procedures, our results are similar to other studies reporting a similar number of interventions. 20,21,27 There is a consensus that fetal therapies should be conducted in Fetal…”

“…3,7,8,[15][16][17] This is partly due to FAV carrying extremely low risks for the mother but high risks for the fetus, with a procedural mortality rate of 4%-32%. [16][17][18][19][20][21] Another challenge is the variability in LV growth and function after a successful FAV. 22,23 Additionally, some fetuses diagnosed with CAS evolving to HLHS show a biventricular outcome after birth without prenatal intervention.…”

“…Although there is agreement on the criteria for identifying patients with CAS evolving to HLHS, the selection of fetuses benefiting from FAV remains a matter of discussion 3,7,8,15–17 . This is partly due to FAV carrying extremely low risks for the mother but high risks for the fetus, with a procedural mortality rate of 4%–32% 16–21 . Another challenge is the variability in LV growth and function after a successful FAV 22,23 .…”