Significance of pre and post-implant MELD-XI score on survival in children undergoing VAD implantation

BACKGROUND: Derangements in liver and renal function often accompany end-stage heart failure. We sought to assess the utility of an objective risk assessment tool, the Model for End-stage Liver Disease eXcluding INR (MELD-XI), to identify pediatric patients at increased risk for adverse outcomes postventricular assist device (VAD) implantation. METHODS: The Pedimacs database was queried for all pediatric patients who underwent VAD implantation from September 19, 2012 to December 31, 2019. Pre-implant and early (1-week) post-implant MELD-XI scores were used to stratify patients into low, intermediate and high score cohorts. Comparison of pre-implant characteristics and post-implant outcomes were conducted across groups. Multiphase parametric hazard modeling was utilized to identify independent predictors of post-implant mortality. RESULTS: A total of 742 patients had a calculable MELD-XI score pre-implant. When stratified by MELD-XI scores pre-implant, patients in the high MELD-XI score cohort (score >13.6) had inferior survival and increased bleeding, renal dysfunction and respiratory failure post-implant compared to intermediate and low score cohorts. Risk factors for mortality post-VAD implantation were: increasing MELD-XI scores (HR 1.1 per 1 unit rise), Pedimacs profile 1 (HR 1.6), congenital heart disease (HR 2.3) and being on a percutaneous VAD (HR 2.7). Importantly, MELD-XI score was a better predictor of post-VAD implant mortality than bilirubin or creatinine alone, neither of which were significant in the final model. Patients with increasing or continued high MELD-XI scores early post-implant had the worst survival. CONCLUSION: The MELD-XI is an easily calculated score that serves as a promising risk assessment tool in identifying children at risk for poor outcomes post VAD implantation. J Heart Lung Transplant 2021;40:1614-1624 (c) 2021 International Society for Heart and Lung Transplantation. All rights reserved.