LAUSR

BACKGROUND The relationship between temporal progression of magnetic resonance elastography derived liver stiffness (MRE-LS) and progression of Fontan associated liver disease (FALD) is unknown. To assess this relationship, we hypothesized that progression of MRE-LS correlated with progression FALD severity and clinical outcomes. METHODS Retrospective review of Fontan patients who had >1 liver MRE, 2010-2016. Annual change in MRE-LS was the quotient of the difference between baseline and subsequent MRE-LS, and the interval between scans. RESULTS 22 patients were enrolled; median age 29(19-38) years, 14 (64%) males and 10 (46%) with atriopulmonary Fontan. Baseline and subsequent MRE-LS values were 5.4 ± 1.1 kPa and 5.8 ± 0.9 kPa" for clarity, interval between scans was 25 ± 5 months, and annual change in MRE-LS was 0.3 ± 0.2 kPa. Temporal change in MRE-LS correlated with temporal changes in model for end-stage liver disease (MELD) score (r = 0.84, p < 0.001) and model for end-stage liver disease excluding international normalized ratio (MELD-XI) score (r = 0.75, p = 0.001). The study cohort was divided into 2 groups using the mean annual change in MRE-LS as the cut point. Groups A and B comprised of patients with annual increase in MRE-LS ≥0.3 kPa (n = 6) and <0.3 kPa (n = 16) respectively. Composite adverse event endpoint (death, heart-liver transplant listing, palliative care, hospitalization, paracentesis) was more common in Group A (4 of 6, 67%) compared to Group B (3 of 16, 19%), p = 0.13 although this did not reach statistical significance due to small sample size. CONCLUSIONS Progression of MRE-LS correlated with clinical deterioration as measured by worsening liver disease severity scores and the occurrence of adverse events.