Aortic Valve Surgery After Neonatal Balloon Aortic Valvuloplasty in Congenital Aortic Stenosis

Abstract

Background: We sought to identify predictive factors for aortic valve (AoV) surgery after neonatal balloon aortic valvuloplasty (BAV) and characterize clinical outcomes of AoV surgery after neonatal BAV. Methods: Time-to-event analysis identified predictors for AoV surgery after neonatal BAV. Clinical outcomes of AoV surgery following neonatal BAV were examined. Results: This study included 96 consecutive patients who underwent neonatal BAV for congenital aortic stenosis between 1998 and 2018, in 26 of whom a fetal BAV had been performed. Fifty-six patients underwent AoV surgery at a median age of 2.0 years. Significant risk factors for AoV surgery in univariate Cox regression (result presented as hazard ratio [HR], [95% CI]; P value) were a history of fetal BAV (HR, 4.05 [95% CI, 2.19-7.40]; P<0.001), AoV annulus diameter Z score (HR, 0.56 [95% CI, 0.43-0.75]; P=0.001), the presence of endocardial fibroelastosis (HR, 2.61 [95% CI, 1.48-4.51]; P=0.001), severe left ventricular dysfunction before neonatal BAV (HR, 1.75 [95% CI, 1.03-2.97]; P=0.04), and recent era (HR, 3.08 [95% CI, 1.68-5.91]; P=0.0002) in the entire cohort. Area under the receiver operating characteristic curve and Youden J index analysis identified a cutoff value for AoV annulus diameter Z score of-2.6 in patients without fetal BAV. In 24 patients with midterm cardiac catheterization data, univariate linear regression analysis (result presented as B coefficient [95% CI]; P) showed that the presence of greater-than-moderate aortic regurgitation immediately after BAV (B coefficient, 4.8 [95% CI, 1.0-8.6]; P=0.018) and before AoV surgery (B coefficient, 6.1 [95% CI, 2.2-10.0]; P=0.004) were significant risk factors for elevated left ventricular end-diastolic pressure after AoV surgery, while concomitant endocardial fibroelastosis resection at AoV surgery had a protective effect (B coefficient,-3.8 [95% CI,-7.6 to-0.06]; P=0.05). Conclusions: A small AoV annulus diameter Z score with a cutoff value of-2.6 and a history of fetal BAV were significantly associated with AoV surgery after neonatal BAV. Concomitant endocardial fibroelastosis resection is recommended at AoV surgery following neonatal BAV to improve left ventricular diastolic function.