Late gestation predictors of a postnatal biventricular circulation after fetal aortic valvuloplasty

Abstract

Objectives: Fetal aortic valvuloplasty (FAV) for severe aortic stenosis (AS) has shown promise in averting progression to hypoplastic left heart syndrome. After FAV, predicting which fetuses will achieve a biventricular (BiV) circulation after birth remains challenging. Identifying predictors of postnatal circulation on late gestation echocardiography will improve parental counseling. Methods: Liveborn patients who underwent FAV and had late gestation echocardiography available were included (2000-2017, n ¼ 96). Multivariable logistic regression and classification and regression tree analysis were utilized to identify independent predictors of BiV circulation. Results: Among 96 fetuses, 50 (52.1%) had BiV circulation at the time of neonatal discharge. In multivariable analysis, independent predictors of biventricular circulation included left ventricular (LV) long axis z-score (OR 3.2, 95% CI 1.8-5.7, p < 0.001), LV ejection fraction (OR 1.3, 95% CI 1.0-1.8, p ¼ 0.023), anterograde aortic arch flow (OR 5.0, 95% CI 1.2-20.4, p ¼ 0.024), and bidirectional or right-toleft foramen ovale flow (OR 4.6, 95% CI 1.4-15.8, p ¼ 0.015). Conclusion: Several anatomic and physiologic parameters in late gestation were found to be independent predictors of BiV circulation after FAV. Identifying these predictors adds to our understanding of LV growth and hemodynamics after FAV and may improve parental counseling. Key Points What's already known about this topic? � Midgestation fetuses with aortic stenosis often progress to hypoplastic left heart syndrome by birth, requiring single ventricle palliation � Fetal aortic valvuloplasty has the potential to improve fetal left heart growth and increase the likelihood of achieving postnatal biventricular circulation What does this study add? � Our study identifies late gestation predictors of postnatal biventricular circulation after fetal aortic valvuloplasty, including left ventricular long axis dimension z-score, left

Hemodynamic and anatomic changes after fetal aortic valvuloplasty are associated with procedural success and postnatal biventricular circulation

“…Our findings are consistent with prior investigations at our institution and others characterizing physiologic parameters at single time points after FAV, demonstrating that antegrade flow across the AoA and improved flow pattern across the foramen ovale (bidirectional flow rather than exclusively left-to-right flow) are associated with both technical success as well as biventricular outcome. 9,11,14,18 In multivariable modeling, change over time in these two physiologic predictors through late gestation had the strongest association with biventricular outcome. These findings suggest that hemodynamic changes after FAV persist in most patients and are indicative of improvements in LV output and compliance.…”

“…Prior work has also demonstrated that late gestation LV EF is also associated with biventricular outcome. 14 However, when incorporating change over time, LV EF is no longer significantly associated with biventricular outcome, likely due to baseline differences in EF. In addition to LV systolic function, LV contribution to cardiac output and diastolic function improve after FAV and may be predictive of postnatal circulatory outcome but have not been fully evaluated in a large cohort followed into late gestation.…”

“…8,9,[11][12][13] Fetal predictors of outcomes at discrete time points during gestation have previously been reported. 8,9,11,12,14 However, there are limited data characterizing the trajectory of left heart growth and hemodynamics following successful FAV into late gestation and no data on whether change in these parameters from baseline is predictive of postnatal outcomes. 8,12,15 This study aims to compare the trajectory of left heart growth and hemodynamic parameters between patients who had a technically successful FAV and those with technically unsuccessful cases.…”

“…Prior work from our institution and other centers has identified that 55%–60% of patients in the current era achieve biventricular circulation after FAV 8,9,11–13 . Fetal predictors of outcomes at discrete time points during gestation have previously been reported 8,9,11,12,14 . However, there are limited data characterizing the trajectory of left heart growth and hemodynamics following successful FAV into late gestation and no data on whether change in these parameters from baseline is predictive of postnatal outcomes 8,12,15 .…”

Hypoplastic Left Heart Syndrome: Is There a Role for Fetal Therapy?

“…This includes improved antegrade aortic valve flow with antegrade aortic arch perfusion in some cases by the time of discharge, improvement of left ventricular filling with change of the mitral valve Doppler from a short monophasic to a biphasic inflow pattern, and in some cases flow reversal at the atrial level to a bidirectional or right to left shunt (40). These hemodynamic changes, if seen later in gestation, have been shown to be predictive of a biventricular outcome (41). Some patients may have severe aortic regurgitation after fetal aortic valvuloplasty.…”