Hepatic Venous Pressure Gradient in Fontan Physiology Has Limited Diagnostic and Prognostic Significance

Background: Hepatic venous pressure gradient (HVPG) is measure of portal pressure and a prognostic tool in patients with viral and alcoholic cirrhosis; its utility is unknown in patients with Fontan-associated liver disease (FALD). Limited data suggest that patients with FALD have normal HVPG. On the basis of the available data, we hypothesized that there would be no association between HVPG, liver disease severity, and transplant-free survival in FALD. Methods: A retrospective study of Fontan patients who had liver biopsy and HVPG assessment at Mayo Clinic was performed. HVPG was calculated as wedged HVP minus free HVP; liver disease severity was measured by histologic assessment of fibrosis and standard clinical liver disease risk scores. Results: Of 56 patients (aged 28 ± 7 years), the mean Fontan pressure was 16 ± 4 and the mean HVPG was 1.4 ± 0.3 mm Hg (range, 0-3). Perisinusoidal fibrosis and periportal fibrosis were present in 56 (100%) and 54 (94%) patients, respectively; 18 (32%) met criteria for cirrhosis. There was no correlation between HVPG and degree of hepatic fibrosis. Similarly, there was no correlation between HVPG and any clinical liver disease risk score. Six (11%) patients died and 2 (4%) underwent heart transplantation during follow-up; HVPG was not associated with transplant-free survival. Conclusions: HVPG is not elevated in FALD even in the setting of cirrhosis and does not correlate with liver disease severity or clinical outcomes. These results suggest the limited diagnostic and prognostic role of HVPG in the management of FALD and highlight the potential pitfalls of using HVPG in this population.