Assessing hepatic impairment in Fontan-associated liver disease using the HepQuant SHUNT test.

BACKGROUND & AIMS: Fontan surgery for single ventricle congenital heart disease leads to Fontan-associated liver disease (FALD). Typical laboratory tests, imaging, and histopathology cannot predict clinical severity in FALD. HepQuant SHUNT is a proprietary serum test of hepatic function and physiology that has not yet been evaluated in FALD. METHODS: Fourteen adult FALD patients at a single urban tertiary care center who underwent a Fontan procedure in childhood received HepQuant SHUNT testing between September 2015 and April 2018. The HepQuant SHUNT disease severity index (DSI) assesses global liver function and physiology from systemic and portal hepatic filtration rates (HFRs, clearances adjusted for body mass) of orally and intravenously administered cholates labeled with deuterium or 13C. The SHUNT parameter of the test measures portal systemic shunting from the ratio of Systemic HFR to Portal HFR. Chart review included laboratory tests, imaging, and clinical findings. Data from FALD patients were compared with data from healthy controls. RESULTS: The average DSI and SHUNT values for the FALD patients were 17.5% and 36.1%, respectively, compared to 9.2% and 24.1%, respectively, for controls. Twelve (85.7%) FALD patients had a DSI >15 (upper limit of normal). Seven (50.0%) FALD patients had SHUNT values >30% (upper limit of normal), while three FALD patients (21.4%) had SHUNT values >49%. One FALD patient with preoperative SHUNT of 69%, who underwent a combined heart-liver transplant, had confirmed cirrhotic morphology within the liver explant. CONCLUSIONS: This pilot study demonstrated that most FALD patients had hepatic impairment detected by abnormal DSI, with a smaller number having markedly elevated SHUNT values >49% suggesting intrinsic liver disease. The HepQuant SHUNT test may be useful in detecting and quantifying liver disease severity in FALD patients.

Assessment of Advanced Liver Fibrosis and the Risk for Hepatic Decompensation in Patients With Congestive Hepatopathy.

Congestive hepatopathy (CH) arises from chronically elevated right-sided heart pressures transmitted to the liver by passive venous congestion. Over time, CH can lead to hepatic bridging fibrosis, decompensated cirrhosis, and hepatocellular carcinoma. Currently, there are no evidence-based guidelines to direct appropriate screening or management of patients with CH, partly because of the inability of current clinical tools (serum tests, imaging studies, liver stiffness measurements, and liver biopsy) to accurately estimate hepatic fibrosis or the risk for hepatic decompensation. The Model for End-Stage Liver Disease excluding international normalized ratio (MELD-XI) score is the only validated serum-based test to predict clinical outcomes in CH. Noninvasive liver stiffness measurements are proving to be of minimal utility as all patients with CH have elevated values that currently cannot differentiate between congestion and fibrosis. In addition, fibrosis staging by liver biopsy is difficult to standardize because of heterogeneous collagen deposition in CH. Moreover, liver biopsy results have little predictive value for post-heart transplant hepatic outcomes in patients with CH. Evaluating liver nodules and masses is also complicated in CH as the finding of delayed venous washout in nodules is not specific for hepatocellular carcinoma in the background of a congested liver, and these lesions may require biopsy to confirm the diagnosis. The lack of effective clinical tools for predicting liver fibrosis and liver function suggests the need for the development of novel biomarkers in patients with CH to assist in the management of this complicated disease. (Hepatology 2018; 00:000-000).

The utility of pulmonary function testing in predicting outcomes following liver transplantation.

Although pulmonary function tests (PFTs) are routinely performed in patients during the evaluation period before liver transplantation (LT), their utility in predicting post-LT mortality and morbidity outcomes is not known. The aim of this study was to determine the impact of obstructive and/or restrictive lung disease on post-LT outcomes. We conducted a retrospective analysis of patients who had pre-LT PFTs and underwent a subsequent LT (2007-2013). We used statistical analyses to determine independent associations between PFT parameters and outcomes (graft/patient survival, time on ventilator, and hospital/intensive care unit [ICU] length of stay [LOS]). A total of 415 LT recipients with available PFT data were included: 65% of patients had normal PFTs; 8% had obstructive lung disease; and 27% had restrictive lung disease. There was no difference in patient and graft survival between patients with normal, obstructive, and restrictive lung disease. However, restrictive lung disease was associated with longer post-LT time on ventilator and both ICU and hospital LOS (P < 0.05). More specific PFT parameters (diffusing capacity of the lungs for carbon monoxide, total lung capacity, and residual volume) were all significant predictors of ventilator time and both ICU and hospital LOS (P < 0.05). Although pre-LT PFT parameters may not predict post-LT mortality, restrictive abnormalities correlate with prolonged post-LT ventilation and LOS. Efforts to identify and minimize the impact of restrictive abnormalities on PFTs might improve such outcomes. Liver Transplantation 22 805-811 2016 AASLD.