Abstract 11778: Comparison of Prenatal Diagnosis Rates and Cardiac Morphometry in Fetal Coarctation by Ultimate Surgical Repair Type

Abstract

Background: Fetal diagnosis of coarctation of aorta is challenging, with limited data examining prenatal detection rates in patients requiring simple vs. extensive arch reconstruction. This study aims to evaluate prenatal detection rate s and fetal cardiac morphometric differences in neonates requiring simple vs. complex coarctation repair. Methods: Pre- and postnatal records of neonates with isolated coarctation repair from the Society of Thoracic Surgeons database from Jan 2010 - Dec 2020 at our center were reviewed. Patients were classified as requiring discrete (Group 1) or extended arch repair (Group 2). Fetal echocardiograms were measured by a single observer blinded to repair type. Results: Of 228 neonates requiring repair, 67 (29%) had a prenatal diagnosis. The proportion with prenatal diagnosis was not different in group 1 (28%) vs. group 2 (32%) (χ2 = 0.45, p = 0.5). At the first fetal echo (median gestational age (GA) of 21.9 wks in group 1 vs 23.6 wks in group 2, p = 0.2), there were no differences between groups when comparing right ventricular (RV) and left ventricular (LV) dimensions, valvular dimensions, or aortic arch dimensions. At the final fetal echo (median GA of 33.7 wks in both groups, p = 0.6), there were statistical differences between group 1 and 2 in RV geometry with ratio of RV minor to major axis (0.72 vs 0.83, p = 0.03) and ratio of LV to RV minor axis (0.68 vs 0.59, p = 0.02), ascending aorta Z score (-2.6 vs -3.4, p = 0.03), distal arch Z score (-3.9 vs -4.6, p = 0.048), and ratio of isthmus to distal arch dimension (0.88 vs 1.02, p = 0.045) (Figure). Conclusion: The rate of prenatal diagnosis in fetuses requiring neonatal coarctation repair remains low, regardless of ultimate surgical repair type. Fetuses ultimately requiring extensive arch repair have smaller aortic sizes, and greater RV/LV size disproportion in the third trimester. This data may be useful in counseling families with regard to postnatal surgical management in fetuses with suspected coarctation.