Technical Success and Serious Adverse Events for Fetal Aortic Valvuloplasty in a Large 20-Year Cohort

FAV is offered to fetuses with severe aortic valve stenosis and evolving hypoplastic left heart syndrome. An inferential analysis of TS and SAE in a large series has not been reported. The purpose of this study was to determine factors associated with fetal aortic valvuloplasty (FAV) technical success (TS) and serious adverse events (SAEs). Retrospective, single-center, cohort analysis of attempted FAV from March 1, 2000, to December 31, 2020. The primary outcome was the TS of FAV, and the secondary outcome was the presence of an SAE. One hundred sixty-five FAVs were attempted in 163 patients with a median gestational age of 24.6 weeks (IQR: 22.9-27.1 weeks). FAV TS was 85% (141/165) and was higher in the 2010 to 2020 era (94% [85/90] vs 75% [56/75]; P < 0.001). Pre-FAV echocardiographic left ventricle (LV) long axis dimension z-score >−0.10 (P < 0.001) and higher LV ejection fraction (P = 0.037) were independently associated with a higher odds of TS. There were 117 SAEs in 67 attempted FAVs (41%), 13 of which were fetal deaths (7.9%). By classification and regression tree analysis, gestational age <21 weeks or in older fetuses, a procedure time of ≥39.6 minutes was associated with higher SAE rate. In the multivariable logistic regression model correcting for gestational age, fetuses with an LV end-diastolic volume <4.09 mL had an age-adjusted OR of 4.71 (95% CI: 1.67-13.29; P = 0.004) for experiencing an SAE. TS of FAV has improved over time, and failure is associated with smaller fetal left heart sizes. SAEs are common and are associated with smaller left hearts and longer procedure times.