Abstract 4138238: A Tense Race: Correlation of Liver Stiffness with Ultrasound Elastography and Hemodynamics in Fontan Patients.

Background: Ultrasound elastography (USE) is a non-invasive tool to diagnose and monitor liver fibrosis. Patients with Fontan physiology are predisposed to congestive hepatopathy, progressive liver fibrosis, and end-stage liver disease. We sought to determine whether hemodynamics pre- and post-Fontan are associated with increased liver stiffness on USE. Methods: A single-center retrospective study included Fontan patients who had one or more USE between 06/2008-03/2024. Liver stiffness was reported as shear wave elastography (SWE) in m/s. Hemodynamic data pre- and post-Fontan and recent echocardiographic data were collected. Data was analyzed as continuous (linear regression model) and as a dichotomous variable (t-test). Results: A total of 78 post-Fontan USE results in 56 patients were analyzed. Table 1 describes the demographics of our patient population. The spectrum of fibrosis based on USE was normal (3.8%), mild (10.3%), moderate (55.1%) and severe (30.8%). In patients with more than one USE, the average increase in SWE was 0.04m/s per month. Pre-Fontan median Glenn pressure was 12mmHg [IQR 13, 15] (p=0.83). On post-Fontan catheterization, median Fontan pressure was 18mmHg [16, 21] (p=0.86). We did not find a significant correlation between hemodynamics and severity of liver stiffness on USE (Tables 2&3). No correlation was seen between USE and severity of ventricular function or atrioventricular valve regurgitation. SWE as a function of time from Fontan operation (<5 yr, 5-10 yrs, >10 yrs) did not vary significantly. Conclusions: USE as a marker of liver congestion does not correlate with hemodynamics pre- or post-Fontan. Further studies are necessary to determine the clinical utility of USE in Fontan patients.