Abstract 13267: Early Predictors of High-Risk Lymphatic Subtypes on T2-Weighted MRI in Patients After Superior Cavopulmonary Connection

Abstract

Introduction: Lymphatic subtype as determined by T2-weighted MRI (T2-CMR) after superior cavopulmonary connection (SCPC) is known to predict clinical outcome after Fontan. Factors related to lymphatic subtype development are not well understood. This study aims to identify early predictors of high-risk lymphatic subtypes. Methods: Retrospective cohort study of consecutive patients with pre-Fontan T2-CMR from 2017 to 2021. Patients divided into two groups based on lymphatic subtype: Group 1 - subtypes 1, 2, and 3; Group 2 - subtypes 3+ (defined as type 3 with history of chylothorax) and 4. Pearson’s chi square, Fisher’s exact, Wilcoxon rank sum, univariate and multivariate logistic regression analysis were performed. Results: We identified 171 patients. The groups differed significantly in total hospital, ICU, and chest tube days, number of catheterizations and number of cardiac surgeries (Table 1). Moderate or greater atrioventricular valve regurgitation (Mod+ AVVR), increased catheterizations and increased chest tube days were associated with high-risk lymphatic subtype. Maintenance of antegrade pulmonary blood flow at the time of SCPC was not significant (Table 2). In multivariate analysis, Mod+ AVVR and number of chest tube days remained in the model after adjusting for other covariates. Overall model significance was 0.007 with an area under the curve of 0.777. Conclusions: Mod+ AVVR and increased chest tube days are predictive of high-risk lymphatic subtype. Further study is needed to determine if lymphatic subtype is acquired via clinical exposure or whether native lymphatic subtype may be predictive of clinical course even prior to cavopulmonary connection.