Histone Deacetylase Inhibitors Show a Potential Leishmanicidal Effect against Leishmania braziliensis in a Mouse Infection Model and Lead to Less Toxicity than Glucantime

Leishmania braziliensis is the primary cause of cutaneous leishmaniasis (CL) in the New World. Current treatments have significant limitations, including severe side effects and parasite resistance. Histone deacetylases (HDAC) are critical regulators of chromatin structure and represent potential drug targets for leishmaniasis. This study evaluated three HDAC inhibitors (HDACi), TH60, TH74, and TH85, in BALB/c mice infected with L. braziliensis, comparing their efficacy to the standard treatment, glucantime. Two doses were tested, and lesion size, parasite load, kidney and liver enzyme levels, and histopathological analyses were carried out. HDACi effectively reduced lesion size and parasite presence, with lower toxicity and fewer organ alterations than glucantime. Among the tested compounds, TH60 was the best-tested HDACi. These findings highlight the potential application of the tested HDACi as leishmanicidal agents against L. braziliensis, positioning them as promising candidates for developing new drugs targeting cutaneous leishmaniasis.

Under the Influence: The Epidemic of Excessive Alcohol Use and Its Impact on Heart and Liver Health

Alcohol use disorder (AUD) is seen in 7% of the world population. In 2019, nearly 3 in 10 adults in the United States (US) consumed аlсоhοl in an unhealthy manner. This alcohol misuse that further increased during the coronavirus disease 2019 pandemic is now persisting, and is associated with rising rates of alcohol-associated hospitalizations, end-organ disease, death, and need for liver transplantation. The current lifetime risk of AUD in the US is estimated to be >30%, and with the steadily rising alcohol consumption in the US, this risk is expected to continue to increase. The effect of excessive alcohol on human health is associated with its lifetime cumulative use and is further impacted by factors like age, gender, nutritional status, concurrent cigarette smoking or drug use, diabetes, increased body weight, kidney disease, other cardiovascular diseases and socio-economic status. In this review we present the complex interplay between alcoholic liver and heart diseases, describing the natural history of each organ involvement and identifying risk factors that are associated with the progression of various alcohol-related end-organ diseases. Abstaining from alcohol or moderating its consumption has been shown to reduce the progression of heart failure, arrhythmias, and hypertension linked to excessive alcohol intake, as well as help prevent alcoholic liver disease. Focus on the identification of other modifiable risk factors associated with various organ injuries in conjunction with public health policies for the safe use of alcohol is needed to mitigate the risk of an impending epidemic of AUD.

Fontan-Associated Liver Disease

Fontan-associated liver disease (FALD) occurs in all patients who have undergone Fontan palliation for functional single ventricle congenital heart defects. While liver fibrosis is universal in patients who have undergone Fontan palliation, FALD may lead to more serious consequences including portal hypertension, cirrhosis, and hepatocellular carcinoma. Scientific studies of the pathophysiology and clinical management of FALD have been limited to date by the heterogeneous nature of the disease, relatively small population of patients with Fontan physiology, and inaccuracy of noninvasive staging tests. As survival after the Fontan procedure improves, the population of adults with Fontan physiology is growing, leading to more severe extracardiac complications related to the Fontan circulation and growing demand for heart and liver transplantation. The accurate evaluation, staging, and management of FALD comprises a clinical challenge which requires expert multidisciplinary input.

Hypointense Findings on Hepatobiliary Phase MR Images

Hepatobiliary (HB) contrast agents are increasingly valuable diagnostic tools in MRI, offering a wider range of applications as their clinical use expands. Normal hepatocytes take up HB contrast agents, which are subsequently excreted in bile. This property creates a distinct HB phase providing valuable insights into liver function and biliary anatomy. HB contrast agents can assist in diagnosing a broad spectrum of HB diseases ranging from diffuse liver disease to focal hepatic lesions and can delineate anatomic details of the biliary tree. Understanding the pharmacodynamics of HB contrast agents is paramount to their appropriate clinical application and troubleshooting. HB phase hypointensity can arise from various diffuse and focal abnormalities that may or may not be associated with biliary excretion. Hypointensity during the HB phase can be broadly grouped into diffuse hypointensity, regional hypointensity, and focal lesions for better evaluation of the underlying cause. Abnormalities may arise from hepatic parenchymal, biliary, or vascular causes, or a combination thereof in each of the broad groups. Recognition of a suboptimal hypointense HB phase is important in the evaluation of focal lesions in patients with cirrhosis of the liver and particularly in those with hepatocellular carcinoma. Furthermore, hypointensity can also suggest the aggressiveness of malignancies such as hepatocellular carcinoma or colorectal metastases, which may affect the prognosis. It is essential to consider all imaging findings relative to the clinical context and the complete set of the MRI sequences performed for diagnosis of liver abnormalities. This comprehensive approach minimizes the risk of misinterpretation or pitfalls. The authors aim to equip radiologists with key insights for accurately understanding hypointensity in the HB phase, ultimately leading to more accurate diagnoses. ©RSNA, 2025 Supplemental material is available for this article.

Hepatic Sinusoidal Disorders

Hepatic sinusoids are highly specialized microcirculatory conduits within the hepatic lobules that facilitate liver functions. The sinusoids can be affected by various disorders, including sinusoidal dilatation, sinusoidal obstruction syndrome (SOS), sinusoidal cellular infiltration, perisinusoidal infiltration, and endothelial neoplasms, such as hemangioendothelioma and angiosarcoma. While these disorders, particularly SOS and neoplasms, can be life threatening, their clinical manifestation is often nonspecific. Patients may present with right upper quadrant pain, jaundice, hepatomegaly, ascites, splenomegaly, and unexplained weight gain, although the exact manifestation depends on the cause, severity, and duration of the disease. Ultimately, invasive tests may be necessary to establish the diagnosis. A comprehensive understanding of imaging manifestations of various sinusoidal disorders contributes to early diagnosis and can help radiologists detect subclinical disease. Additionally, specific imaging features may assist in identifying the cause of the disorder, leading to a more focused and quicker workup. For example, a mosaic pattern of enhancement of the liver parenchyma is suggestive of sinusoidal dilatation; peripheral and patchy reticular hypointensity of the liver parenchyma on hepatobiliary MR images is characteristic of SOS; and associated diffuse multiple hyperintensities on diffusion-weighted images may be specific for malignant sinusoidal cellular infiltration. The authors provide an overview of the pathogenesis, clinical features, and imaging appearances of various hepatic sinusoidal disorders, with a special emphasis on SOS. ©RSNA, 2024 Supplemental material is available for this article.

Congestive Hepatopathy: Pathophysiology, Workup, and Imaging Findings with Pathologic Correlation

Liver congestion is increasingly encountered in clinical practice and presents diagnostic pitfalls of which radiologists must be aware. The complex altered hemodynamics associated with liver congestion leads to diffuse parenchymal changes and the development of benign and malignant nodules. Distinguishing commonly encountered benign hypervascular lesions, such as focal nodular hyperplasia (FNH)-like nodules, from hepatocellular carcinoma (HCC) can be challenging due to overlapping imaging features. FNH-like lesions enhance during the hepatic arterial phase and remain isoenhancing relative to the background liver parenchyma but infrequently appear to wash out at delayed phase imaging, similar to what might be seen with HCC. Heterogeneity, presence of an enhancing capsule, washout during the portal venous phase, intermediate signal intensity at T2-weighted imaging, restricted diffusion, and lack of uptake at hepatobiliary phase imaging point toward the diagnosis of HCC, although these features are not sensitive individually. It is important to emphasize that the Liver Imaging Reporting and Data System (LI-RADS) algorithm cannot be applied in congested livers since major LI-RADS features lack specificity in distinguishing HCC from benign hypervascular lesions in this population. Also, the morphologic changes and increased liver stiffness caused by congestion make the imaging diagnosis of cirrhosis difficult. The authors discuss the complex liver macro- and microhemodynamics underlying liver congestion; propose a more inclusive approach to and conceptualization of liver congestion; describe the pathophysiology of liver congestion, hepatocellular injury, and the development of benign and malignant nodules; review the imaging findings and mimics of liver congestion and hypervascular lesions; and present a diagnostic algorithm for approaching hypervascular liver lesions. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Imaging of Fontan-Associated Liver Disease

ABSTRACT

The Fontan procedure is the definitive treatment for patients with single-ventricle physiology. Surgical advances have led to a growing number of patients surviving into adulthood. Fontan-associated liver disease (FALD) encompasses a spectrum of pathologic liver changes that occur secondary to altered physiology including congestion, fibrosis, and the development of liver masses. Assessment of FALD is difficult and relies on using imaging alongside of clinical, laboratory, and pathology information. Ultrasound, computed tomography, and magnetic resonance imaging are capable of demonstrating physiologic and hepatic parenchymal abnormalities commonly seen in FALD. Several novel imaging techniques including magnetic resonance elastography are under study for use as biomarkers for FALD progression. Imaging has a central role in detection and characterization of liver masses as benign or malignant. Benign FNH-like masses are commonly encountered; however, these can display atypical features and be mistaken for hepatocellular carcinoma (HCC). Fontan patients are at elevated risk for HCC, which is a feared complication and has a poor prognosis in this population. While imaging screening for HCC is widely advocated, no consensus has been reached regarding an optimal surveillance regimen.

Metformin ameliorates liver fibrosis induced by congestive hepatopathy via the mTOR/HIF-1α signaling pathway

INTRODUCTION AND OBJECTIVES

Congestive hepatopathy (CH) is a hepatic vascular disease that results in chronic liver congestion, which can lead to liver fibrosis. New uses of metformin have been discovered over the years. However, the function of metformin in congestive liver fibrosis is not yet fully understood. This study aimed to investigate the effect of metformin on liver fibrosis in a mouse model of CH.

MATERIALS AND METHODS

Partial ligation of the inferior vena cava (pIVCL) was used to establish a mouse model of liver congestion. Metformin (0.1%) was added to the daily drinking water of the animals, and the effect of metformin on liver tissue was studied after 6 weeks. Hepatic stellate cells (HSCs) were also stimulated with CoCl2 to investigate the inhibitory impact of metformin on the mammalian target of rapamycin (mTOR)/hypoxia-inducible factor-1α (HIF-1α) pathway.

RESULTS

Metformin attenuated liver congestion; decreased the expression of collagen, fibronectin, α-smooth muscle actin (α-SMA), and HIF-1α; and ameliorated liver fibrosis in pIVCL mice. The proliferation and migration of HSCs were inhibited by metformin in vitro, which prevented α-SMA expression and restrained HSC activation. The expression levels of phosphorylated-mTOR, HIF-1α, and vascular endothelial growth factor were also decreased.

CONCLUSIONS

Metformin inhibits CH-induced liver fibrosis. Functionally, this beneficial effect may be the result of inhibition of HSC activation and of the mTOR/HIF-1α signaling pathway.

The Liver in Heart Failure: From Biomarkers to Clinical Risk

Heart failure (HF) is a clinical syndrome due to heart dysfunction, but in which other organs are also involved, resulting in a complex multisystemic disease, burdened with high mortality and morbidity. This article focuses on the mutual relationship between the heart and liver in HF patients. Any cause of right heart failure can cause hepatic congestion, with important prognostic significance. We have analyzed the pathophysiology underlying this double interaction. Moreover, we have explored several biomarkers and non-invasive tests (i.e., liver stiffness measurement, LSM) potentially able to provide important support in the management of this complex disease. Cardiac biomarkers have been studied extensively in cardiology as a non-invasive diagnostic and monitoring tool for HF. However, their usefulness in assessing liver congestion in HF patients is still being researched. On the other hand, several prognostic scores based on liver biomarkers in patients with HF have been proposed in recent years, recognizing the important burden that liver involvement has in HF. We also discuss the usefulness of a liver stiffness measurement (LSM), which has been recently proposed as a reliable and non-invasive method for assessing liver congestion in HF patients, with therapeutic and prognostic intentions. Lastly, the relationship between LSM and biomarkers of liver congestion is not clearly defined; more research is necessary to establish the clinical value of biomarkers in assessing liver congestion in HF patients and their relationship with LSM.

Prognostic Value of Liver Fibrotic Markers in Patients With Heart Failure

Several liver fibrotic markers are associated with prognosis in patients with heart failure (HF). However, the optimal markers for outcome prediction remain unclear. This study aimed to simultaneously investigate the prognostic value of liver fibrotic markers and the associations between these markers and clinical parameters in patients with HF without organic liver disease. We prospectively examined 211 consecutive patients with chronic HF between April 2018 and August 2021, excluding those with organic liver disease, using liver magnetic resonance imaging and ultrasound. A total of 7 representative liver fibrotic markers were measured in all patients. The primary outcome of interest was the composite of all-cause death and hospitalization for worsening HF. During a median follow-up period of 747 (interquartile range 465 to 1,042) days, the primary outcome occurred in 45 patients. Patients with higher hyaluronic acid and type III procollagen N-terminal peptide (P-III-P) levels showed a significantly higher incidence of the primary outcome than those without (p <0.001 and p = 0.005, respectively). The multivariable Cox regression analysis revealed that hyaluronic acid and P-III-P levels were independently associated with the risk of adverse events (hazard ratio 1.84, 95% confidence interval 1.18 to 2.87 and hazard ratio 2.89, 95% confidence interval 1.32 to 6.34, respectively) even after adjustment for a mortality prediction model, whereas the other 5 markers were not associated with the primary outcome. In conclusion, among the representative liver fibrotic markers, hyaluronic acid and P-III-P might be the optimal markers for outcome prediction in patients with HF.

Rare causes of abdominal pain: a primer for the admitting general surgeon

The broad uptake of the acute surgical unit (ASU) model of surgical care in Australia has resulted in general surgeons becoming increasingly involved in the management of patients with acute abdominal pain (AAP), some of whom will be labelled as having non-specific abdominal pain (NSAP) (Kinnear N, Jolly S, Herath M, et al. The acute surgical unit: An updated systematic review and meta-analysis. review. Int. J. Surg. 2021;94:106109; Lehane CW, Jootun RN, Bennett M, Wong S, Truskett P. Does an acute care surgical model improve the management and outcome of acute cholecystitis? ANZ J. Surg. 2010;80:438-42). NSAP patients lack a clear diagnosis of surgical pathology based on standard clinical, laboratory and imaging work-up, although they may require ASU admission for pain control and assessment. This article provides a review of uncommon conditions, presenting as AAP, that could possibly be mis-labelled as NSAP, with a focus on aspects of the presentation that may aid diagnosis and management including specific demographic features, clinical findings, key investigations and initial treatment priorities for ASU clinicians. Ultimately, most of the conditions discussed will not require surgical intervention, however, they require a diagnosis to be made and initial treatment planning before on-referral to the appropriate specialty. For the on-call general surgeon, some knowledge of these conditions and an index of suspicion are invaluable for the prompt diagnosis and efficient management of these patients.

Liver Fibrosis, Fat, and Iron Evaluation with MRI and Fibrosis and Fat Evaluation with US: A Practical Guide for Radiologists

Quantitative imaging biomarkers of liver disease measured by using MRI and US are emerging as important clinical tools in the management of patients with chronic liver disease (CLD). Because of their high accuracy and noninvasive nature, in many cases, these techniques have replaced liver biopsy for the diagnosis, quantitative staging, and treatment monitoring of patients with CLD. The most commonly evaluated imaging biomarkers are surrogates for liver fibrosis, fat, and iron. MR elastography is now routinely performed to evaluate for liver fibrosis and typically combined with MRI-based liver fat and iron quantification to exclude or grade hepatic steatosis and iron overload, respectively. US elastography is also widely performed to evaluate for liver fibrosis and has the advantage of lower equipment cost and greater availability compared with those of MRI. Emerging US fat quantification methods can be performed along with US elastography. The author group, consisting of members of the Society of Abdominal Radiology (SAR) Liver Fibrosis Disease-Focused Panel (DFP), the SAR Hepatic Iron Overload DFP, and the European Society of Radiology, review the basics of liver fibrosis, fat, and iron quantification with MRI and liver fibrosis and fat quantification with US. The authors cover technical requirements, typical case display, quality control and proper measurement technique and case interpretation guidelines, pitfalls, and confounding factors. The authors aim to provide a practical guide for radiologists interpreting these examinations. © RSNA, 2023 See the invited commentary by Ronot in this issue. Quiz questions for this article are available in the supplemental material.

Liver Fibrosis Markers Represent Central Venous Pressure in Post-pubertal Patients With Congenital Heart Disease

Background Central venous pressure (CVP) is one of the most important hemodynamic parameters in patients with congenital heart disease (CHD). In adults, it is well-known that liver fibrosis markers reflect CVP, but this is not well-understood in children. We investigated the liver fibrosis markers in pediatric CHD patients and their ability to predict CVP. Methods We studied 160 patients who underwent cardiac catheterization in our hospital between January 2017 and December 2020. The levels of the fibrotic markers, including type IV collagen 7s, procollagen type III peptide, and hyaluronic acid, were measured. Results Procollagen type III peptide was markedly elevated in infants younger than one year of age. From one to 15 years of age, it was slightly lower than in the infant group, with a peak at around 10 years of age. In the age group of 16 years and older, most of its values were generally high. Type IV collagen 7s and hyaluronic acid levels were high in infants, with no significant differences at later ages. Procollagen type III peptide and hyaluronic acid showed no significant correlation with CVP in any of the age groups, whereas type IV collagen 7s significantly correlated with CVP in the age group above one year old. Conclusions We found that elevated liver fibrosis markers, particularly type IV collagen 7s, correlated with central venous pressure in CHD patients older than one year. Measurement of liver fibrosis markers may allow the early detection of changes in CVP and liver function in patients with CHD.

Fontan-associated liver disease: Diagnosis, surveillance, and management

The Fontan operation is a lifesaving procedure for patients with functional single-ventricle congenital heart disease, where hypoplastic left heart syndrome is the most frequent anomaly. Hemodynamic changes following Fontan circulation creation are now increasingly recognized to cause multiorgan affection, where the development of a chronic liver disease, Fontan-associated liver disease (FALD), is one of the most important morbidities. Virtually, all patients with a Fontan circulation develop liver congestion, resulting in fibrosis and cirrhosis, and most patients experience childhood onset. FALD is a distinctive type of congestive hepatopathy, and its pathogenesis is thought to be a multifactorial process driven by increased nonpulsatile central venous pressure and decreased cardiac output, both of which are inherent in the Fontan circulation. In the advanced stage of liver injury, complications of portal hypertension often occur, and there is a risk of developing secondary liver cancer, reported at young age. However, FALD develops with few clinical symptoms, a surprisingly variable degree of severity in liver disease, and with little relation to poor cardiac function. The disease mechanisms and modifying factors of its development are still not fully understood. As one of the more important noncardiac complications of the Fontan circulation, FALD needs to be diagnosed in a timely manner with a structured monitoring scheme of disease development, early detection of malignancy, and determination of the optimal time point for transplantation. There is also a clear need for consensus on the best surveillance strategy for FALD. In this regard, imaging plays an important role together with clinical scoring systems, biochemical workups, and histology. Patients operated on with a Fontan circulation are generally followed up in cardiology units. Ultimately, the resulting multiorgan affection requires a multidisciplinary team of healthcare personnel to address the different organ complications. This article discusses the current concepts, diagnosis, and management of FALD, with special emphasis on the role of different imaging techniques in the diagnosis and monitoring of disease progression, as well as current recommendations for liver disease surveillance.

Liver stiffness assessed by magnetic resonance elastography predicts clinical outcomes in patients with heart failure and without chronic liver disease

OBJECTIVES

Evaluation of liver stiffness (LS) by magnetic resonance elastography (MRE) is useful for estimating right atrial pressure (RAP) in patients with heart failure (HF). However, its prognostic implications are unclear. We sought to investigate whether LS measured by MRE (LS-MRE) could predict clinical outcomes in patients with HF.

METHODS

We prospectively examined 207 consecutive HF patients between April 2018 and May 2021 after excluding those with organic liver disease. All patients underwent 3.0-T MRE. The primary outcome of interest was the composite of all-cause death and hospitalisation for HF.

RESULTS

During a median follow-up period of 720 (interquartile range [IQR] 434-1013) days, the primary outcome occurred in 44 patients (21%), including 15 (7%) all-cause deaths and 29 (14%) hospitalisations for HF. The patients were divided into two groups according to median LS-MRE of 2.54 (IQR 2.34-2.82) kPa. Patients with higher LS-MRE showed a higher incidence of the primary outcome compared to those with lower LS-MRE (p < 0.001). Multivariable Cox regression analyses revealed that LS-MRE value was independently associated with the risk of adverse events (hazard ratio 2.49, 95% confidence interval 1.46-4.24). In multivariable linear regression, RAP showed a stronger correlation with LS-MRE (β coefficient = 0.31, p < 0.001) compared to markers related to liver fibrosis.

CONCLUSIONS

In patients without chronic liver disease and presenting with HF, elevated LS-MRE was independently associated with worse clinical outcomes. Elevated LS-MRE may be useful for risk stratification in patients with HF and without chronic liver disease.

KEY POINTS

• Magnetic resonance elastography (MRE) is an emerging non-invasive imaging technique for evaluating liver stiffness (LS) which can estimate right atrial pressure. • Elevated LS-MRE, which mainly reflects liver congestion, was independently associated with worse clinical outcomes in patients with heart failure. • The assessment of LS-MRE would be useful for stratifying the risk of adverse events in heart failure patients without chronic liver disease.

MR elastography in primary sclerosing cholangitis: a pictorial review

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by biliary ductal inflammation and fibrosis causing both intrahepatic and extrahepatic biliary strictures and dilatation. There is currently no effective medical treatment and the disease leads to cirrhosis and liver failure, with patients often requiring liver transplantation in end-stage disease. Liver fibrosis is one of the most important factors in determining patient outcome in PSC, and the diagnosis and monitoring of fibrosis are vital to patient care. MRI with magnetic resonance cholangiopancreatography is the non-invasive imaging modality of choice in PSC and is useful for the evaluation of parenchymal and biliary changes. Biliary ductal abnormalities, however, cannot always predict the presence of liver fibrosis and alternative means are needed. MR Elastography (MRE) is the most accurate non-invasive method for assessing liver fibrosis and is particularly helpful in PSC due to unique hepatic manifestations. Like other non-invasive modalities, MRE measures liver stiffness as an indirect method for assessing fibrosis. Given the ability of MRE to assess liver fibrosis and the importance of fibrosis in PSC patients, MRE can reliably predict patient outcome. In this pictorial review, we will review MR findings of PSC, with an emphasis on MRE, and demonstrate scenarios where MRE is particularly helpful in evaluating PSC patients.

Liver and heart failure: an ultrasound relationship

Liver and heart are anatomically and patho-physiologically related. In heart failure (HF) the increased right atrial pressure and volume overload cause histological changes in hepatocytes, leading to a condition known as "congestive hepatopathy" (CH), with consequent variations in liver functioning and ultrasound (US) findings. CH has specifical US findings especially regarding venous vessels aspect, easily detecting by gray-scale study, but many others can be distinguished by Doppler analysis. Usually, hepatic veins look enlarged and hypocollassing, together with signs of portal hypertension (hepatomegaly, ascites, splenomegaly, porto-systemic collaterals). Typically, in CH Doppler findings regard alterations in venous vessel flow and arterial resistance (venous system hyperpulsatility, reduced velocity flow, high resistance index in hepatic arterial Doppler spectrum). Sometimes CH and other primary hepatopathy can coexist, and therefore some of the expected variations may not manifest: it allows suspecting an unknown underlying liver disease. At last, US technologies of more recent applications, even if not routinely used, allow investigating additional aspects such as elastography that detects changes in liver elasticity or contrastographic US, able to show differences in hepatic venous opacification. However, most of these US signs are not pathognomonic, and therefore a multidisciplinary clinical reasoning must not be lacking. The aim of the present review is to easily provide US signs of liver alterations in HF, in particular right heart failure with volume overload, suggesting including liver US in instrumental diagnosis and therapeutic monitoring of HF.

Micro-scale assessment of bone quality changes in adult cadaveric men with congestive hepatopathy

Congestive hepatopathy (CH) is a chronic liver disease (CLD) caused by impaired hepatic venous blood outflow, most frequently resulting from congestive heart failure. Although it is known that heart failure and CLDs contribute to increased risk for age-related fractures, an assessment of CH-induced skeletal alterations has not been made to date. The aim of our study was to characterize changes in bone quality in adult male cadavers with pathohistologically confirmed CH compared with controls without liver disease. The anterior mid-transverse part of the fifth lumbar vertebral body was collected from 33 adult male cadavers (age range 43-89 years), divided into the CH group (n = 15) and the control group (n = 18). We evaluated trabecular and cortical micro-architecture and bone mineral content (using micro-computed tomography), bone mechanical competence (using Vickers micro-hardness tester), vertebral cellular indices (osteocyte lacunar network and bone marrow adiposity), and osteocytic sclerostin and connexin 43 expression levels (using immunohistochemistry staining and analysis). Deterioration in trabecular micro-architecture, reduced trabecular and cortical mineral content, and decreased Vickers microhardness were noted in the CH group (p < 0.05). Reduced total number of osteocytes and declined connexin 43 expression levels (p < 0.05) implied that harmed mechanotransduction throughout the osteocyte network might be present in CH. Moreover, elevated expression levels of sclerostin by osteocytes could indicate the role of sclerostin in mediating low bone formation in individuals with CH. Taken together, these micro-scale bone alterations suggest that vertebral strength could be compromised in men with CH, implying that vertebral fracture risk assessment and subsequent therapy may need to be considered in these patients. However, further research is required to confirm the clinical relevance of our findings.

Remdesivir-Induced Liver Injury in a Patient With Coronavirus Disease 2019 and History of Congestive Hepatopathy

Remdesivir is an antiviral agent used as supportive care in adults with SARS-COV2-induced pneumonia. We report a case of an 81-year-old patient who developed hepatocellular acute liver injury 48 hours after initiating remdesivir. During the investigation, other causes of hepatotoxicity were excluded. A decrease in transaminases and international normalized ratio (INR) was observed 24 hours after cessation of remdesivir. An abdominal CT demonstrated hepatic congestion, retrograde hepatic venous opacification shortly after intravenous contrast injection, and dilatation of hepatic veins and inferior vena cava. We suggest congestive hepatopathy secondary to remdesivir as a possible component of liver injury.

Combined hepatocellular carcinoma-cholangiocarcinoma in a patient with Fontan-associated liver disease

We present a rare case of combined hepatocellular carcinoma-cholangiocarcinoma in a woman with a history of univentricular congenital heart disease requiring multiple corrective operations including Fontan procedure. During workup for elevated alpha fetal protein, a right hepatic lobe lesion was identified with biopsy showing poorly differentiated hepatocellular carcinoma. She underwent successful segment 5 liver resection. Final pathology demonstrated combined hepatocellular carcinoma-cholangiocarcinoma. She was treated with gemcitabine/oxaliplatin adjuvant chemotherapy and had no evidence of recurrent disease at her 12-month follow-up. To our knowledge, this is the first case reported in of successful treatment of this rare malignancy in the setting of Fontan-associated liver disease and highlights the importance of a robust screening protocol in this patient population. Semiannual screening for the development of primary liver malignancy should start by 10 years post-Fontan and continue until heart-liver transplantation may be performed. It is important to note that cirrhosis is not a pre-requisite for the development of hepatocellular carcinoma or cholangiocarcinoma in these patients.

Striking Elevations in Aminotransferases in a Case of Congestive Hepatopathy Without Concurrent Hypotension

Congestive hepatopathy results from passive venous congestion often in the setting of right heart failure. Injury to the liver due to congestion is often asymptomatic and may be difficult to recognize and diagnose. The degree of elevations in aminotransferases varies in cases of congestive hepatopathy but usually stays within two to three times the upper limit of normal. Here, we report an interesting case of congestive hepatopathy that presented with striking elevations of aminotransferases in the 2000s international units/liter a few days after admission without concurrent hypotension.

Hepatocellular carcinoma diagnosed in a patient who had Fontan operation 30 years ago: a case report

The Fontan operation is performed in patients with a single ventricle. As the systemic venous return is directly connected to the pulmonary circulation during this procedure, chronic hepatic congestion is induced, leading to Fontan-associated liver disease (FALD) including liver cirrhosis and hepatocellular carcinoma (HCC). In this report, we present a case of HCC diagnosed in a patient who underwent the Fontan operation 30 years ago. The patient underwent regular surveillance for FALD, which revealed a 4 cm-sized hepatic mass with elevated serum alpha-fetoprotein. After surgical treatment, there was no evidence of HCC recurrence during 3 years of follow-up. As the risk of HCC and Fontan-associated liver cirrhosis increases with the duration elapsed since the operation, regular surveillance should be emphasized. Serial follow-up of serum alpha-fetoprotein levels and abdominal imaging are necessary to achieve early and accurate diagnosis of HCC in post-Fontan patients.

Use of liver stiffness measurements in acute decompensated heart failure: new applications of a non-invasive technique

Heart failure (HF) is a complex disease associated with multisystem organ failure, recurrent hospital admissions, and increased mortality. Acute decompensated heart failure (ADHF) increases central venous pressure (CVP) with resultant hepatic congestion, and this relationship has prognostic significance. The gold standard method of measuring CVP, right heart catheterization, is invasive and costly, prompting further investigation into more accurate non-invasive assessments in HF patients, including liver elastography. Liver elastography relies on imaging techniques to assess liver stiffness measurements (LSM), with high values equating to increased stiffness. While this was developed to assess fibrosis in liver disease, LSM also reflect increased CVP and hepatic congestion. Multiple studies involving ADHF patients, find that increased LSM are independently predictive of increased cardiac events, all-cause mortality, and worse post-operative outcome after both acute HF exacerbation and left ventricular assist device (LVAD) placement. In this review, we discuss the role of LSM as a surrogate for CVP and their applications in determining prognosis in both the ADHF and LVAD populations.

Part 2: Disease of the Heart and Liver: A Relationship That Cuts Both Ways

Diseases known to affect both the heart and liver include a variety of infectious, autoimmune, and metabolic disorders, as well as toxins: most commonly alcohol. As damage to both the heart and liver progresses, transplantation is a reasonable therapeutic option. Heart failure patients with underlying congestive hepatopathy receiving cardiac transplant have demonstrated improved liver enzyme levels posttransplant. Patients with severe end-stage liver disease requiring a liver transplant must undergo careful preoperative evaluation as surgical stress exposes the myocardium to high levels of catecholamines. Clinicians must consider both cardiac and hepatic complications when evaluating heart failure, cirrhosis, and nonalcoholic fatty liver disease. In Part 2 of this review, we discuss new noninvasive techniques for assessing liver fibrosis in the preoperative stage. Both serum and radiologic studies, such as transient elastography, have begun to take the place of liver biopsy due to their decreased morbidity. Last, we explore the current research examining the benefit of combined heart-liver transplant, although more longitudinal outcome studies are needed.

Part 1: Disease of the Heart and Liver: A Relationship That Cuts Both Ways

The heart and the liver display multifaceted, complex interactions that can be divided into cardiac effects of liver disease, hepatic effects of heart disease, and disease processes affecting both organs. In part 1 of this 2 part series, we discuss how acute and chronic heart failure can have devastating effects on the liver, such as acute cardiogenic liver injury and congestive hepatopathy. On the other hand, primary liver disease, such as cirrhosis, can lead to a plethora of cardiac insults representative in cirrhotic cardiomyopathy as systolic dysfunction, diastolic dysfunction, and electrophysiological disturbances. Nonalcoholic fatty liver disease has long been associated with cardiovascular events that increase mortality. The management of both disease processes changes when the other organ system becomes involved. This consideration is important with regard to a variety of interventions, most notably transplantation of either organ, as risk of complications dramatically rises in the setting of both heart and liver disease (discussed in part 2). As our understanding of the intricate communication between the heart and liver continues to expand so does our management.

A deep learning framework for automated detection and quantitative assessment of liver trauma

Background

Both early detection and severity assessment of liver trauma are critical for optimal triage and management of trauma patients. Current trauma protocols utilize computed tomography (CT) assessment of injuries in a subjective and qualitative (v.s. quantitative) fashion, shortcomings which could both be addressed by automated computer-aided systems that are capable of generating real-time reproducible and quantitative information. This study outlines an end-to-end pipeline to calculate the percentage of the liver parenchyma disrupted by trauma, an important component of the American Association for the Surgery of Trauma (AAST) liver injury scale, the primary tool to assess liver trauma severity at CT.

Methods

This framework comprises deep convolutional neural networks that first generate initial masks of both liver parenchyma (including normal and affected liver) and regions affected by trauma using three dimensional contrast-enhanced CT scans. Next, during the post-processing step, human domain knowledge about the location and intensity distribution of liver trauma is integrated into the model to avoid false positive regions. After generating the liver parenchyma and trauma masks, the corresponding volumes are calculated. Liver parenchymal disruption is then computed as the volume of the liver parenchyma that is disrupted by trauma.

Results

The proposed model was trained and validated on an internal dataset from the University of Michigan Health System (UMHS) including 77 CT scans (34 with and 43 without liver parenchymal trauma). The Dice/recall/precision coefficients of the proposed segmentation models are 96.13/96.00/96.35% and 51.21/53.20/56.76%, respectively, in segmenting liver parenchyma and liver trauma regions. In volume-based severity analysis, the proposed model yields a linear regression relation of 0.95 in estimating the percentage of liver parenchyma disrupted by trauma. The model shows an accurate performance in avoiding false positives for patients without any liver parenchymal trauma. These results indicate that the model is generalizable on patients with pre-existing liver conditions, including fatty livers and congestive hepatopathy.

Conclusion

The proposed algorithms are able to accurately segment the liver and the regions affected by trauma. This pipeline demonstrates an accurate performance in estimating the percentage of liver parenchyma that is affected by trauma. Such a system can aid critical care medical personnel by providing a reproducible quantitative assessment of liver trauma as an alternative to the sometimes subjective AAST grading system that is used currently.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12880-022-00759-9.

Semiquantitative characterization of dynamic magnetic resonance perfusion of the liver in pediatric Fontan patients

BACKGROUND

Dynamic contrast-enhanced magnetic resonance imaging (MRI) of the liver in pediatric Fontan patients often shows peripheral reticular areas of hypoenhancement, which has not been studied in detail.

OBJECTIVE

To semiquantitatively score the hepatic MR perfusion abnormality seen in pediatric Fontan patients, and to correlate the perfusion abnormality with functional clinical and hemodynamic parameters.

MATERIALS AND METHODS

All children (< 18 years old) after Fontan palliation with combined clinical cardiac and liver MRI performed between May 2017 and April 2019 were considered for inclusion. A semiquantitative perfusion score was used to assess the severity of the hepatic reticular pattern seen on dynamic contrast-enhanced liver imaging. The liver was divided into four sections: right posterior, right anterior, left medial and left lateral. Each liver section was assigned a score from 0 to 4 depending on the amount of abnormal reticular hypoenhancement. Scoring was assigned for each section of the liver across eight successive dynamic contrast-enhanced modified spoiled gradient echo runs. Scores were correlated with clinical and hemodynamic parameters.

RESULTS

All Fontan children showed hepatic reticular hypoenhancement by MRI, most severe in the early portal venous phase with a median maximum total perfusion abnormality score of 12 (range: 9-14). All perfusion abnormalities progressively resolved during the hepatic venous phase. Perfusion abnormality scores were greatest in the right compared to left hepatic lobes (7 range: [6-8] vs. 5 [range: 3-6], P < 0.01). The maximum left hepatic lobe perfusion abnormality scores were greatest in children with versus without imaging signs of portal hypertension (8 [range: 7-8] vs. 4 [range: 3-5], P < 0.01). High unconjugated bilirubin and low platelets correlated with greater perfusion abnormality (R = 0.450, P = 0.024, and R =  - 0.458, P < 0.01, respectively). Age at MRI, time from Fontan, focal liver lesions and cardiac MRI hemodynamic parameters did not show significant correlations with the severity of the liver perfusion abnormality.

CONCLUSION

All Fontan children have hepatic reticular hypoenhancement abnormalities seen with MRI that are most severe in the right hepatic lobe and universally show gradual resolution through the hepatic venous phase. Perfusion abnormality in the left hepatic lobe is worse in children with portal hypertension.

Congestive hepatopathy: the role of the radiologist in the diagnosis

The liver has a complex vascularization and is subjected to a high metabolic demand, making it vulnerable to hemodynamic changes. As a result, several pathologies can develop, one of which is congestive hepatopathy. This disease occurs secondary to various cardiovascular conditions that generate a persistent passive venous congestion in the liver, which in the long term can culminate in fibrosis and cirrhosis, which in turn increases the risk of developing hepatocellular carcinoma. In order to avoid this outcome, early diagnosis is crucial; however, both the clinical presentation and laboratory tests are unspecific, and they are only altered in advanced stages of the disease. One form of early detection is through imaging findings, there being various useful modalities such as Doppler ultrasonography (US), computed tomography, and magnetic resonance imaging. The purpose of this article is to detail the imaging findings of congestive hepatopathy in the different available modalities, with special emphasis on Doppler US, highlighting the role of the radiologist in the suspicion of this disease. We summarize the pathophysiologic mechanisms of congestive hepatopathy, clinical findings, and provide description of its main differential diagnoses.

The inferior vena cava: anatomical variants and acquired pathologies

The inferior vena cava (IVC) is the largest vein in the body, draining blood from the abdomen, pelvis and lower extremities. This pictorial review summarises normal anatomy and embryological development of the IVC. In addition, we highlight a wide range of anatomical variants, acquired pathologies and a common pitfall in imaging of the IVC. This information is essential for clinical decision making and to reduce misdiagnosis.

MR Imaging of Diffuse Liver Disease

The liver performs many vital functions for the human body. It stores essential vitamins and minerals, such as iron and vitamins A, D, K, and B₁₂. It synthesizes proteins, such as blood clotting factors, albumin, and glycogen, as well as cholesterol, carbohydrates, and triglycerides. Additionally, it acts as a detoxifier, metabolizing and helping to clear alcohol, drugs, and ammonia. Typical MR imaging protocols for liver imaging include T2-weighted, chemical shift imaging, and precontrast and postcontrast T1-weighted sequences. This article discussed MR imaging of diffuse liver diseases and their typical imaging findings.

Noninvasive assessment of congestive hepatopathy in patients with constrictive pericardial physiology using MR relaxometry

BACKGROUND

Constrictive pericarditis represents a treatable cause of mainly right heart failure (RHF), characterized by increased filling pressures and congestive hepatopathy. We hypothesized assessment of T1 and T2 liver relaxation times enables to depict liver congestion, and thus to diagnose RHF.

METHODS

Cardiovascular magnetic resonance imaging (CMR) was performed in 45 pericarditis patients i.e., 25 with constrictive physiology (CP+), 20 with normal physiology (CP-), and 30 control subjects. CMR included morphologic and functional assessment of the heart and pericardium. Liver relaxation times were measured on T1 and T2 cardiac maps.

RESULTS

CP+ and CP- patients were predominantly male, but CP+ patients were on average 13 years older than CP- patients (p = 0.003). T1 and T2 Liver values were significantly higher in CP+ than in CP- patients and controls, i.e. T1: 765 ± 102 ms vs 581 ± 56 ms and 537 ± 30 ms (both p < 0.001); T2: 63 ± 13 ms vs 50 ± 4 ms and 46 ± 4 ms (both p < 0.001). Extracellular volume (ECV) liver values were also increased, i.e. 42 ± 7% CP+ vs 31 ± 3% CP- and 30 ± 3% control (both p < 0.001). Using a cut-off right atrial pressure of >5 mmHg to discriminate between normal and increased pressure, native T1 liver yielded the highest AUC (0.926) at ROC analysis with a sensitivity of 79.3% and specificity of 95.6%. Gamma-glutamyl transpeptidase correlated well withT1 liver (r² = 0.43) and ECV liver (r² = 0.30). Excellent intra- and inter-reader agreement was found for T1, T2 and ECV measurement of the liver.

CONCLUSIONS

Assessment of liver relaxation times in pericarditis patients provide valuable information on the presence of concomitant congestive hepatopathy, reflecting RHF.

Assessment of Right-Sided Heart Failure in Patients with Dilated Cardiomyopathy using Magnetic Resonance Relaxometry of the Liver

In non-ischemic dilated cardiomyopathy (DC) patients at risk of developing right heart failure (RHF), early depiction of congestive heart failure (CHF) is pivotal to inform about the hemodynamic status and tailor medical therapy. We hypothesized increased liver relaxation times measured at routine cardiovascular magnetic resonance (CMR), reflecting passive hepatic congestion, may be a valuable imaging biomarker to depict congestive heart failure. The study cohort consisted of DC patients with LV dysfunction (i.e., ejection fraction <35%) with (n = 48) and without (n = 46) right ventricular dysfunction (RVD), defined as a right ventricular ejection fraction <35%, and >45%, respectively, and a control group (n = 40). Native T1, T2, and extracellular volume (ECV) liver values were measured on routinely acquired cardiac maps. DC+RVD patients had higher C-reactive protein, troponin I and NT-pro BNP values, and worse LV functional parameters than DC-RVD patients (all p <0.001). T1, T2 and ECV Liver values were significantly higher in DC+RVD compared to DC-RVD patients and controls, that is, T1: 675 ± 88 ms verses 538 ± 39 ms and 540 ± 34 ms; T2: 54± 8 ms versus 45 ± 5 ms and 46 ± 4 ms; ECV: 36 ± 7% versus 29 ± 4% and 30 ± 3% (all p <0.001). Gamma-glutamyltranspeptidase (GGT) correlated moderately but significantly with native T1 (r² = 0.34), T2 (r² = 0.27), and ECV liver (r² = 0.23) (all p <0.001). Using right atrial (RA) pressure, as surrogate measure of RHF (i.e., RA pressure >5 mm Hg), native T1 liver yielded at ROC analysis the highest area under the curve (0.906), significantly higher than ECV liver (0.813), GGT (0.806), T2 liver (0.797), total bilirubin (0.737) and alkaline phosphatase (0.561)(p = 0.04). A T1 value of 617 ms yielded a sensitivity of 79.5% and specificity of 91.0% to depict RHF. Excellent intra-/inter-observer agreement was found for assessment of native T1/T2/ECV liver values. In conclusion, in DC patients, assessment of liver relaxation times acquired on a cardiovascular magnetic resonance exam, may provide valuable information with regard to the presence of RHF.

Liver segmental volume and attenuation ratio (LSVAR) on portal venous CT scans improves the detection of clinically significant liver fibrosis compared to liver segmental volume ratio (LSVR)

Background

The aim of this proof-of-concept study was to show that the liver segmental volume and attenuation ratio (LSVAR) improves the detection of significant liver fibrosis on portal venous CT scans by adding the liver vein to cava attenuation (LVCA) to the liver segmental volume ratio (LSVR).

Material and methods

Patients who underwent portal venous phase abdominal CT scans and MR elastography (reference standard) within 3 months between 02/2016 and 05/2017 were included. The LSVAR was calculated on portal venous CT scans as LSVR*LVCA, while the LSVR represented the volume ratio between Couinaud segments I-III and IV-VIII, and the LVCA represented the density of the liver veins compared to the density in the vena cava. The LSVAR and LSVR were compared between patients with and without significantly elevated liver stiffness (based on a cutoff value of 3.5 kPa) using the Mann–Whitney U test and ROC curve analysis.

Results

The LSVR and LSVAR allowed significant differentiation between patients with (n = 19) and without (n = 122) significantly elevated liver stiffness (p < 0.001). However, the LSVAR showed a higher area under the curve (AUC = 0.96) than the LSVR (AUC = 0.74). The optimal cutoff value was 0.34 for the LSVR, which detected clinically increased liver stiffness with a sensitivity of 53% and a specificity of 88%. With a cutoff value of 0.67 for the LSVAR, the sensitivity increased to 95% while maintaining a specificity of 89%.

Conclusion

The LSVAR improves the detection of significant liver fibrosis on portal venous CT scans compared to the LSVR.

Abdominal Imaging of Children and Young Adults With Fontan Circulation: Pathophysiology and Surveillance

OBJECTIVE. The Fontan procedure has significantly improved the survival in children with a functional single ventricle, but it is associated with chronically elevated systemic venous pressure that leads to multisystemic complications. Imaging plays an important role in assessing these complications and guiding management. The pathophysiology, imaging modalities, and current surveillance recommendations are discussed and illustrated. CONCLUSION. Significant improvement in survival of patients with Fontan circulation is associated with ongoing cardiac and extracardiac comorbidities and multisystemic complications. The liver and intestines are particularly vulnerable to damage. In addition, this patient population has been shown to be at increased risk of certain malignancies such as hepatocellular carcinoma and neuroendocrine tumors. Familiarity with imaging findings of Fontan-associated liver disease and other abdominal complications of the Fontan circulation is essential for radiologists because we are likely to encounter these patients in our general practice.

Congenital heart disease-associated liver disease: a narrative review

Congenital heart diseases (CHD) can be associated with liver dysfunction. The cause for liver impairment can result out of a wide spectrum of different causes, including liver congestion, hypoxemia or low cardiac output. Fortunately, most CHD show a good long-term outcome from a cardiac perspective, but great attention should be paid on non-cardiac health problems that develop frequently in patients suffering from CHD. The treatment of liver dysfunction in CHD requires a close multidisciplinary management in a vulnerable patient collective. Unfortunately, structured recommendations on the management of liver dysfunction in patients with CHD are scarce. The objective of this review is to provide insights on the pathophysiology and etiologies of liver dysfunction as one of the most relevant non-cardiac problems related to CHD. Furthermore, we advise here on the management of liver disease in CHD with special attention on assessment of liver dysfunction, management of portal hypertension as well as on surveillance and management of hepatocellular carcinoma (HCC). A multidisciplinary perspective may help to optimize morbidity and mortality in the long-term course in these patients. However, as evidence is low in many aspects, we encourage the scientific community to perform prospective studies to gain more insights in the treatment of liver dysfunction in patients with CHD.

Calibration of an Electrical Analog Model of Liver Hemodynamics in Fontan Patients

Fontan associated liver disease is a common complication in patients with Fontan circulation, who were born with a single functioning heart ventricle. The hepatic venous pressure gradient (HVPG) is used to assess liver health and is a surrogate measure of the pressure gradient across the entire liver (portal pressure gradient (PPG)). However, it is thought to be inaccurate in Fontan patients. The main objectives of this study were (1) to apply an existing detailed lumped parameter model (LPM) of the liver to Fontan patients using patient-specific clinical data and (2) to determine whether HVPG is a suitable measurement of PPGs in these patients. An existing LPM of the liver blood circulation was applied and tuned to simulate patient-specific liver hemodynamics. Geometries were collected from seven adult Fontan patients and used to evaluate model parameters. The model was solved and tuned using waveform measurements of flows, inlet and outlet pressures. The predicted ratio of portal to hepatic venous pressures is comparable to in vivo measurements. The results confirmed that HVPG is not suitable for Fontan patients, as it would underestimate the portal pressures gradient by a factor of 3 to 4. Our patient-specific liver model provides an estimate of the pressure drop across the liver, which differs from the clinically used metric HVPG. This work represents a first step toward models suitable to assess liver health in Fontan patients and improve its long-term management.

Lessons of the month: Acute liver failure: a case close to the heart

The differential diagnosis of an acute liver injury is extremely broad and can often change following initial investigations. We describe the case of a 54-year-old woman whose liver function derangement was initially attributed to alcohol excess, but in fact turned out to be cardiac in origin. We describe the underlying mechanisms and features of cardiac-related liver injury, and how the pattern of liver tests alongside appropriate imaging can help obtain the diagnosis.

Liver Congestion Assessed by Hepatic Vein Waveforms in Patients With Heart Failure

Background

It has been reported that the pattern of hepatic vein (HV) waveforms determined by abdominal ultrasonography is useful for the diagnosis of hepatic fibrosis in patients with chronic liver disease. We aim to clarify the clinical implications of HV waveform patterns in patients with heart failure (HF).

Methods

We measured HV waveforms in 350 HF patients, who were then classified into 3 categories based on their waveforms: those with a continuous pattern (C group); those whose V wave ran under the baseline (U group), and those with a reversed V wave (R group). We performed right-heart catheterization, and examined the rate of postdischarge cardiac events, such as cardiac death and rehospitalization due to worsening HF.

Results

The number of patients in each of the 3 HV waveform groups was as follows: C group, n = 158; U group, n = 152, and R group, n = 40. The levels of B-type natriuretic peptide (R vs C and U; 245.8 vs 111.7 and 216.6 pg/mL; P < 0.01) and mean right atrial pressure (10.5 vs 6.7 and 7.2 mm Hg; P < 0.01) were highest in the R group compared with the other groups. The Kaplan-Meier analysis found that cardiac event–free rates were lowest in the R group among all groups (log-rank P < 0.001). In the multivariable Cox proportional hazard analysis, the R group was found to be an independent predictor of cardiac events (hazard ratio, 4.90; 95% confidence interval, 2.23-10.74; P < 0.01).

Conclusion

Among HF patients, those with reversed V waves had higher right atrial pressure and were at higher risk of adverse prognosis.

Fontan-associated liver disease

OBJECTIVE

To review the pathophysiology of Fontan-associated liver disease, its histologic changes, and its radiologic manifestations.

CONCLUSIONS

Fontan-associated liver disease is the result of a set of structural and functional changes in the liver that occur secondary to hemodynamic changes brought about by Fontan surgery. The radiologic manifestations of Fontan-associated liver disease consist of changes in the size and shape of the liver, alterations in the signal intensity or pattern of enhancement, abnormalities in the vascular structures, and focal lesions, which include benign nodules with intense uptake in the arterial phase and hepatocellular carcinoma. Radiologists need to be familiar with this disease and its complications, because the number of patients who undergo Fontan surgery continues to increase, and these patients undergo an increasing number of imaging tests.

Hepatic perfusional changes on CT and MRI: a radiology primer

Hepatic perfusional changes are common in response to, or as a result of, a multitude of pathological processes. These can be neoplastic, inflammatory, fibrotic, or ischemic in origin, to name a few. The liver, having a dual blood supply, is a unique organ to study using contrast-enhanced CT and MRI imaging due to its varied appearance on multiphasic imaging. Knowledge of the CT and MRI appearance of hepatic perfusional changes, in addition to the clinical presentation, can often result in an accurate differential diagnosis. Many of the conditions that cause these changes in hepatic blood flow result in similar appearances on imaging. As a result, it is important that radiologists be aware of common pitfalls when dealing with hepatic perfusional changes to prevent misdiagnosis or delayed diagnosis. As such, this review will focus on some of the various causes of hepatic perfusional changes and how to accurately identify and diagnose them based on their CT and MRI appearance.

Hepatic magnetic resonance T1-mapping and extracellular volume fraction compared to shear-wave elastography in pediatric Fontan-associated liver disease

BACKGROUND

Children with Fontan circulation are at risk of developing hepatic fibrosis/cirrhosis. Reliable noninvasive monitoring techniques are lacking or under development.

OBJECTIVE

To investigate surrogate indicators of hepatic fibrosis in adolescents with Fontan circulation by evaluating hepatic magnetic resonance (MR) T1 mapping and extracellular volume fraction measurements compared to US shear-wave elastography.

MATERIALS AND METHODS

We analyzed hepatic native T1 times and extracellular volume fractions with modified Look-Locker inversion recovery. Liver stiffness was analyzed with shear-wave elastography. We compared results between 45 pediatric patients ages 16.7±0.6 years with Fontan circulation and 15 healthy controls ages 19.2±1.2 years. Measurements were correlated to clinical and hemodynamic data from cardiac catheterization.

RESULTS

MR mapping was successful in 35/45 patients, revealing higher hepatic T1 times (774±44 ms) than in controls (632±52 ms; P<0.001) and higher extracellular volume fractions (47.4±5.0%) than in controls (34.6±3.8%; P<0.001). Liver stiffness was 1.91±0.13 m/s in patients vs. 1.20±0.10 m/s in controls (P<0.001). Native T1 times correlated with central venous pressures (r=0.5, P=0.007). Native T1 was not correlated with elastography in patients (r=0.2, P=0.1) or controls (r = -0.3, P=0.3). Extracellular volume fraction was correlated with elastography in patients (r=0.5, P=0.005) but not in controls (r=0.2, P=0.6).

CONCLUSION

Increased hepatic MR relaxometry and shear-wave elastography values in adolescents with Fontan circulation suggested the presence of hepatic fibrosis or congestion. Central venous pressure was related to T1 times. Changes were detected differently with MR relaxometry and elastography; thus, these techniques should not be used interchangeably in monitoring hepatic fibrosis.

Cardiovascular and abdominal flow alterations in adults with morphologic evidence of liver disease post Fontan palliation

BACKGROUND

Although morphologic abnormalities in the liver are commonly encountered post Fontan palliation, the relationships between hepatic morphology, vascular flows, and clinical status remain incompletely understood. We therefore aimed to explore flow characteristics in hepatic and intestinal vessels and to examine cardiovascular associations with liver disease.

METHODS

This was a retrospective study of adults post Fontan palliation undergoing clinically indicated cardiovascular magnetic resonance imaging (MRI). Patients were included if MRI flow quantification was available for cardiac, hepatic and intestinal vessels; patients were excluded if phase-contrast flow imaging was insufficient for analysis.

RESULTS

Thirty patients were studied (median age at MRI 28.5 years [range 19-47]). Eighteen subjects (60%) were classified as having morphologic liver disease according to validated criteria based on available MRI imaging. Abdominal and cardiovascular flows were quantified. Patients with morphologic liver disease had a 41% reduction in superior mesenteric artery (211 ± 124 versus 358 ± 181 mL/min/m², p = .004), a 36% reduction in hepatic vein (496 ± 247 versus 778 ± 220 mL/min/m², p = .01), a 31% reduction in portal vein (399 ± 133 versus 580 ± 159 mL/min/m², p = .004), and an 18% reduction in Fontan pathway flows (1358 ± 429 versus 1651 ± 270 mL/min/m², p = .04) compared with the remaining population. Adverse cardiovascular events were not associated with morphologic liver disease.

CONCLUSION

Morphologic liver disease appears to be associated with flow alterations within the heart, liver and intestine post Fontan palliation. These novel observations suggest that a potential relationship exists between morphologic disease and vascular flows thereby providing further insights into the pathophysiology of liver disease in this high-risk population.

The many faces of cirrhosis

There are many different imaging features of cirrhosis, some of which are less commonly recognized. It is important that the radiologist is familiar with these features as cirrhosis can be first discovered on imaging performed for other indications, thus alerting the clinician for the need to screen for complications of cirrhosis and referral for potential treatment. This article reviews the various imaging findings of cirrhosis seen on cross-sectional imaging of the abdomen and pelvis.

Fontan-Associated Liver Disease: Screening, Management, and Transplant Considerations

Surgical innovation and multidisciplinary management have allowed children born with univentricular physiology congenital heart disease to survive into adulthood. An estimated global population of 70 000 patients have undergone the Fontan procedure and are alive today, most of whom are <25 years of age. Several unexpected consequences of the Fontan circulation include Fontan-associated liver disease. Surveillance biopsies have demonstrated that virtually 100% of these patients develop clinically silent fibrosis by adolescence. As they mature, there are increasing reports of combined heart-liver transplantation resulting from advanced liver disease, including bridging fibrosis, cirrhosis, and hepatocellular carcinoma, in this population. In the absence of a transplantation option, these young patients face a poor quality of life and overall survival. Acknowledging that there are no consensus guidelines for diagnosing and monitoring Fontan-associated liver disease or when to consider heart transplantation versus combined heart-liver transplantation in these patients, a multidisciplinary working group reviewed the literature surrounding Fontan-associated liver disease, with a specific focus on considerations for transplantation.

Fontan-associated liver disease: pathophysiology, investigations, predictors of severity and management

Cardiac hepatopathy is the liver injury resulting from congestion and ischaemia associated with acute or chronic heart failure. The improved longevity of adults with operated congenital heart disease who develop heart failure as an increasingly late event makes this form of liver injury increasingly clinically relevant. Patients with congenital heart disease with a single ventricle anomaly, who require creation of a Fontan circulation, are particularly vulnerable as they have elevated venous filling pressures with chronic liver congestion. Progression to liver fibrosis and eventually cirrhosis may occur, with its associated risks of liver failure and hepatocellular carcinoma. This risk likely increases over the patient's lifetime, related to the duration post-surgical repair and reflects the chronicity of congestion. Liver biopsy is rarely performed due to a higher risk of complications in the setting of elevated venous pressures, and the frequent use of anticoagulation. Non-invasive methods of liver assessment are poorly validated and different factors require consideration compared to other chronic liver diseases. This review discusses the current understanding of cardiac hepatopathy in congenital heart disease patients with a Fontan circulation. This entity has recently been called Fontan Associated Liver Disease in the literature, with the term useful in recognising that the pathophysiology is incompletely understood, and that long-standing venous pressure elevation and hypoxaemia are presumed to play an additional significant role in the pathogenesis of the liver injury.

Hepatic surface grooves in Trinidad and Tobago

PURPOSE

Hepatic surface grooves (HSGs) are prominent depressions on the antero-superior surface of the liver. We sought to document the prevalence of HSGs in an Eastern Caribbean population.

METHODS

We observed all consecutive autopsies performed at a facility in Trinidad and Tobago and recorded the presence, number, location, width, length and depth of any HSG identified. Each liver was then sectioned to document intra-parenchymal abnormalities.

RESULTS

Sixty Autopsies were observed. There were HSGs in 9 (15%) cadavers (5 females and 4 males), at an average age of 66 years (range 48-83, Median 64, SD ± 10.4). The HSGs were located on the diaphragmatic surface of the right hemi-liver in 8 (89%) cadavers, left medial section in 4 (44%), left lateral section in 3 (33%) and coursing along Cantlie's plane in 3 (33%) cadavers. Eight (89%) cadavers with HSGs had other associated anomalies: accessory inferior grooves (5), parenchymal nutmeg changes (5), abnormal caudate morphology (4), hyperplastic left hemi-liver (3), lingular process (2), bi-lobar gallbladder (1) and/or abnormal ligamentous attachments (1).

CONCLUSIONS

Approximately 15% of unselected Afro-Caribbean persons in this Eastern Caribbean population have HSGs. Every attempt should be made to identify HSGs on pre-operative imaging because they can alert the hepatobiliary surgeon to: (1) associated anatomic anomalies in 89% of cases, (2) associated hepatic congestion in 56% of persons, (3) increased risk of bleeding during liver resections and (4) increased technical complexity of liver resections. The association between HSGs, cardiovascular complications, hepatic congestion and nutmeg liver prompted us to propose a new aetiologic mechanism for HSG formation, involving localized hyperplasia at growth zones due to upregulation of beta-catenin levels.