Abstract 12837: A Novel Index to Predict Post-Operative Left Atrioventricular Valve Morbidity in Atrioventricular Septal Defects

Abstract

Introduction: Morbidity of the left atrioventricular valve (LAVV) remains the leading indication for reoperation on atrioventricular septal defects (AVSDs). While qualitative 2D and quantitative 3D risk factors have been identified, no quantitative 2D measurement yet exists to predict poor postoperative outcomes. The aim of this study was to evaluate objective measurements of the LAVV and subvalvar apparatus in relation to postoperative outcomes. Methods: A retrospective review was performed on 2D echocardiograms of patients undergoing surgical repair of an AVSD from January 1, 2014 to December 31, 2021. Demographic and perioperative data were collected from the electronic medical record. The hingepoint-to-hingepoint length of the superior, mural and inferior bridging leaflets in early diastole, as well as LAVV chordal length at end-diastole were measured and indexed to body surface area. A poor outcome was defined by significant LAVV regurgitation (moderate or greater), LAVV stenosis (5mmHg or greater), need for second cardiopulmonary bypass run, postoperative ECMO, reoperation, or death. LAVV measurements were compared to composite outcome by Wilcoxon rank sum test. Results: Of 120 patients with adequate perioperative imaging, 47 (39.2%) had a poor outcome. Indexed LAVV chordal length was significantly different between those who experienced a poor outcome and those who did not, with shorter chordal length predictive of a poor outcome. Interestingly, mural leaflet size was not associated with a poor outcome. Conclusions: Indexed LAVV chordal length is a novel measurement shown to predict a poor postoperative outcome in AVSD. Additional analysis is necessary to assess whether short chords are more predictive of LAVV regurgitation or stenosis, and to determine a numeric cut-off of indexed chordal length for predicting poor outcome.