Patients transplanted for nonalcoholic steatohepatitis are at increased risk for postoperative cardiovascular events

Post-Liver Transplant Metabolic Syndrome

Non-alcoholic steatohepatitis (NASH) is the second most frequent cause of liver transplantation following alcoholic liver disease. With longer follow-up and increased survival rates, the occurrence rate of the metabolic syndrome is increasing with time among liver transplant recipients. Reappearances of non-alcoholic fatty liver disease after transplantation, both as recurring cases and new instances, are prevalent; nonetheless, the recurrence of fibrosis is minimal. Recognizing populations at elevated risk and enhancing the management of metabolic-related conditions are crucial for maintaining a healthy transplanted organ, particularly considering the prolonged utilization of immunosuppressive treatments. Furthermore, NASH-related cirrhosis patients who had transplant are at a greater risk of cardiovascular, renal events and increased incidence of cancer, necessitating a unique care strategy. This review discusses post-transplant metabolic syndrome, risk factors, pathogenesis, diagnosis, prevention strategy, recurrent and de novo NAFLD and customized immunosuppression.

Metabolic-Dysfunction-Associated Steatotic Liver Disease (MASLD) after Liver Transplantation: A Narrative Review of an Emerging Issue

The development of steatotic liver disease after liver transplant (LT) is widely described, and epidemiological data have revealed an increased incidence in recent times. Its evolution runs from simple steatosis to steatohepatitis and, in a small proportion of patients, to significant fibrosis and cirrhosis. Apparently, post-LT steatotic disease has no impact on the recipient's overall survival; however, a higher cardiovascular and malignancy burden has been reported. Many donors' and recipients' risk factors have been associated with this occurrence, although the recipient-related ones seem of greater impact. Particularly, pre- and post-LT metabolic alterations are strictly associated with steatotic graft disease, sharing common pathophysiologic mechanisms that converge on insulin resistance. Other relevant risk factors include genetic variants, sex, age, baseline liver diseases, and immunosuppressive drugs. Diagnostic evaluation relies on liver biopsy, although non-invasive methods are being increasingly used to detect and monitor both steatosis and fibrosis stages. Management requires a multifaceted approach focusing on lifestyle modifications, the optimization of immunosuppressive therapy, and the management of metabolic complications. This review aims to synthesize the current knowledge of post-LT steatotic liver disease, focusing on the recent definition of metabolic-dysfunction-associated steatotic liver disease (MASLD) and its metabolic and multisystemic concerns.

EASL-EASD-EASO Clinical Practice Guidelines on the Management of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously termed non-alcoholic fatty liver disease (NAFLD), is defined as steatotic liver disease (SLD) in the presence of one or more cardiometabolic risk factor(s) and the absence of harmful alcohol intake. The spectrum of MASLD includes steatosis, metabolic dysfunction-associated steatohepatitis (MASH, previously NASH), fibrosis, cirrhosis and MASH-related hepatocellular carcinoma (HCC). This joint EASL-EASD-EASO guideline provides an update on definitions, prevention, screening, diagnosis and treatment for MASLD. Case-finding strategies for MASLD with liver fibrosis, using non-invasive tests, should be applied in individuals with cardiometabolic risk factors, abnormal liver enzymes, and/or radiological signs of hepatic steatosis, particularly in the presence of type 2 diabetes (T2D) or obesity with additional metabolic risk factor(s). A stepwise approach using blood-based scores (such as FIB-4) and, sequentially, imaging techniques (such as transient elastography) is suitable to rule-out/in advanced fibrosis, which is predictive of liver-related outcomes. In adults with MASLD, lifestyle modification - including weight loss, dietary changes, physical exercise and discouraging alcohol consumption - as well as optimal management of comorbidities - including use of incretin-based therapies (e.g. semaglutide, tirzepatide) for T2D or obesity, if indicated - is advised. Bariatric surgery is also an option in individuals with MASLD and obesity. If locally approved and dependent on the label, adults with non-cirrhotic MASH and significant liver fibrosis (stage ≥2) should be considered for a MASH-targeted treatment with resmetirom, which demonstrated histological effectiveness on steatohepatitis and fibrosis with an acceptable safety and tolerability profile. No MASH-targeted pharmacotherapy can currently be recommended for the cirrhotic stage. Management of MASH-related cirrhosis includes adaptations of metabolic drugs, nutritional counselling, surveillance for portal hypertension and HCC, as well as liver transplantation in decompensated cirrhosis.

EASL-EASD-EASO Clinical Practice Guidelines on the management of metabolic dysfunction-associated steatotic liver disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously termed non-alcoholic fatty liver disease (NAFLD), is defined as steatotic liver disease (SLD) in the presence of one or more cardiometabolic risk factor(s) and the absence of harmful alcohol intake. The spectrum of MASLD includes steatosis, metabolic dysfunction-associated steatohepatitis (MASH, previously NASH), fibrosis, cirrhosis and MASH-related hepatocellular carcinoma (HCC). This joint EASL-EASD-EASO guideline provides an update on definitions, prevention, screening, diagnosis and treatment for MASLD. Case-finding strategies for MASLD with liver fibrosis, using non-invasive tests, should be applied in individuals with cardiometabolic risk factors, abnormal liver enzymes, and/or radiological signs of hepatic steatosis, particularly in the presence of type 2 diabetes (T2D) or obesity with additional metabolic risk factor(s). A stepwise approach using blood-based scores (such as FIB-4) and, sequentially, imaging techniques (such as transient elastography) is suitable to rule-out/in advanced fibrosis, which is predictive of liver-related outcomes. In adults with MASLD, lifestyle modification - including weight loss, dietary changes, physical exercise and discouraging alcohol consumption - as well as optimal management of comorbidities - including use of incretin-based therapies (e.g. semaglutide, tirzepatide) for T2D or obesity, if indicated - is advised. Bariatric surgery is also an option in individuals with MASLD and obesity. If locally approved and dependent on the label, adults with non-cirrhotic MASH and significant liver fibrosis (stage ≥2) should be considered for a MASH-targeted treatment with resmetirom, which demonstrated histological effectiveness on steatohepatitis and fibrosis with an acceptable safety and tolerability profile. No MASH-targeted pharmacotherapy can currently be recommended for the cirrhotic stage. Management of MASH-related cirrhosis includes adaptations of metabolic drugs, nutritional counselling, surveillance for portal hypertension and HCC, as well as liver transplantation in decompensated cirrhosis.

The Impact of Metabolic Health and Obesity on Liver Transplant Candidates and Recipients

Poor metabolic health and obesity have significant impacts on the outcomes of patients suffering from chronic liver disease, particularly those with metabolic dysfunction-associated steatotic liver disease. Patients with such comorbidities who require liver transplant evaluation for advancing liver disease or liver failure require special consideration due to increased risk of cardiovascular disease, renal dysfunction, sarcopenic obesity, and cancer. Those who have had a history of prior bariatric surgery pose specific anatomical constraints and may also be at increased risk of alcohol use disorder. Pre-operative risk assessment as well as strict control of metabolic risk factors are essential to reduce intra-operative and post-liver transplant complications. As immunosuppressive therapy exacerbates metabolic dysfunction and risk for cancer, post-liver transplant care must focus on balancing the need to prevent rejection and the impact of progressive metabolic dysfunction in this unique, but growing, patient population.

Cardiovascular disease in patients with metabolic dysfunction-associated steatohepatitis compared with metabolic dysfunction-associated steatotic liver disease and other liver diseases: A systematic review

The burden of cardiovascular disease (CVD) in patients with metabolic dysfunction-associated steatohepatitis (MASH) is poorly characterized, particularly vs other liver diseases including metabolic dysfunction-associated steatotic liver disease (MASLD). To identify available evidence, Embase, MEDLINE, and Cochrane database searches (main search: 2011-September 6, 2021; additional ad hoc search [MEDLINE only]: September 7, 2021-February 15, 2023), plus manual searches (2019-September 2021), were performed. Studies reporting CVD outcomes (angina, coronary artery disease [CAD], heart failure, myocardial infarction, peripheral artery disease, stroke, venous thromboembolic disease, and CV mortality) in adults with histologically confirmed MASH and MASLD or other liver diseases were identified, with studies of MASLD without confirmed MASH excluded. Of 8732 studies, 21 were included. An increased incidence or prevalence of CVD in patients with MASH vs other conditions was reported in 12 studies; odds ratios (OR), where reported, ranged from 3.12 (95 % CI: 1.33-5.32) to 4.12 (95 % CI: 1.91-8.90). The risk of CAD was increased in people with MASH in 6 of 7 studies, while the risk of stroke was increased in 6 of 6 studies, and heart failure in 2 of 4 studies. Three of 6 studies provided evidence of increased CVD-related mortality in patients with MASH vs those without. In conclusion, this literature review suggests that CVD is prevalent in patients with MASH and may contribute to increased mortality. Accordingly, cardiovascular risk factors should be aggressively managed in this population. Whether the CVD burden in patients with MASH is a direct consequence of MASH itself requires further study.

[The Role of the Anaesthesiologist in Liver Transplantation - Preoperative Evaluation]

Preoperative evaluation prior to listing for orthotopic liver transplantation (LT) requires a careful multidisciplinary approach with specialized teams including surgeons, hepatologists and anesthesiologists in order to improve short- and long-term clinical outcomes. Due to inadequate supply of donor organs and changing demographics, patients listed for LT have become older, sicker and share more comorbidities. As cardiovascular events are the leading cause for early mortality precise evaluation of risk factors is mandatory. This review focuses on the detection and management of coronary artery disease, cirrhotic cardiomyopathy, portopulmonary hypertension and hepatopulmonary syndrome in patients awaiting LT. Further insights are being given into scoring systems, patients with Acute-on-chronic-liver-failure (ACLF), frailty, NASH cirrhosis and into psychologic evaluation of patients with substance abuse.

Predicting major adverse cardiovascular events after orthotopic liver transplantation using a supervised machine learning model: A cohort study

BACKGROUND

Liver transplant (LT) patients have become older and sicker. The rate of post-LT major adverse cardiovascular events (MACE) has increased, and this in turn raises 30-d post-LT mortality. Noninvasive cardiac stress testing loses accuracy when applied to pre-LT cirrhotic patients.

AIM

To assess the feasibility and accuracy of a machine learning model used to predict post-LT MACE in a regional cohort.

METHODS

This retrospective cohort study involved 575 LT patients from a Southern Brazilian academic center. We developed a predictive model for post-LT MACE (defined as a composite outcome of stroke, new-onset heart failure, severe arrhythmia, and myocardial infarction) using the extreme gradient boosting (XGBoost) machine learning model. We addressed missing data (below 20%) for relevant variables using the k-nearest neighbor imputation method, calculating the mean from the ten nearest neighbors for each case. The modeling dataset included 83 features, encompassing patient and laboratory data, cirrhosis complications, and pre-LT cardiac assessments. Model performance was assessed using the area under the receiver operating characteristic curve (AUROC). We also employed Shapley additive explanations (SHAP) to interpret feature impacts. The dataset was split into training (75%) and testing (25%) sets. Calibration was evaluated using the Brier score. We followed Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis guidelines for reporting. Scikit-learn and SHAP in Python 3 were used for all analyses. The supplementary material includes code for model development and a user-friendly online MACE prediction calculator.

RESULTS

Of the 537 included patients, 23 (4.46%) developed in-hospital MACE, with a mean age at transplantation of 52.9 years. The majority, 66.1%, were male. The XGBoost model achieved an impressive AUROC of 0.89 during the training stage. This model exhibited accuracy, precision, recall, and F1-score values of 0.84, 0.85, 0.80, and 0.79, respectively. Calibration, as assessed by the Brier score, indicated excellent model calibration with a score of 0.07. Furthermore, SHAP values highlighted the significance of certain variables in predicting postoperative MACE, with negative noninvasive cardiac stress testing, use of nonselective beta-blockers, direct bilirubin levels, blood type O, and dynamic alterations on myocardial perfusion scintigraphy being the most influential factors at the cohort-wide level. These results highlight the predictive capability of our XGBoost model in assessing the risk of post-LT MACE, making it a valuable tool for clinical practice.

CONCLUSION

Our study successfully assessed the feasibility and accuracy of the XGBoost machine learning model in predicting post-LT MACE, using both cardiovascular and hepatic variables. The model demonstrated impressive performance, aligning with literature findings, and exhibited excellent calibration. Notably, our cautious approach to prevent overfitting and data leakage suggests the stability of results when applied to prospective data, reinforcing the model's value as a reliable tool for predicting post-LT MACE in clinical practice.

How best to combine liver transplantation and bariatric surgery?-Results from a global, web-based survey

BACKGROUND AND AIMS

Obesity is a growing healthcare challenge worldwide and a significant risk factor for liver failure as seen with non-alcoholic steatohepatitis (NASH). Combining metabolic-bariatric surgery (MBS) with liver transplantation (LT) appears as attractive strategy to treat both, the underlying liver disease and obesity. However, there is an ongoing debate on best timing and patient selection. This survey was designed to explore the current treatment practice for patients with NASH and obesity worldwide.

METHODS

A web-based survey was conducted in 2022 among bariatric and LT surgeons, and hepatologists from Europe, North and South America and Asia.

RESULTS

The survey completion rate was 74% (145/196). The average respondents were 41-50 years (38%), male (82.1%) and had >20 years of clinical experience (42.1%). Centres with a high LT-caseload for NASH were mainly located in the USA and United Kingdom. Almost 30% have already performed a combination of LT with MBS and 49% plan to do it. A majority of bariatric surgeons prefer MBS before LT (77.2%), whereas most of LT surgeons (52%) would perform MBS during LT. Most respondents (n = 114; 80%) favour sleeve gastrectomy over other bariatric techniques. One third (n = 42; 29.4%) has an established protocol regarding MBS for LT candidates.

CONCLUSION

The most experienced centres doing LT for NASH are in the USA and United Kingdom with growing awareness worldwide. Overall, a combination of MBS and LT has already been performed by a third of respondents. Sleeve gastrectomy is the bariatric technique of choice-preferably performed either before or during LT.

How non-alcoholic fatty liver disease and cirrhosis affect the heart

Liver diseases affect the heart and the vascular system. Cardiovascular complications appear to be a leading cause of death in patients with non-alcoholic fatty liver disease (NAFLD) and cirrhosis. The predominant histological changes in the liver range from steatosis to fibrosis to cirrhosis, which can each affect the cardiovascular system differently. Patients with cirrhotic cardiomyopathy (CCM) and NAFLD are at increased risk of impaired systolic and diastolic dysfunction and for suffering major cardiovascular events. However, the pathophysiological mechanisms behind these risks differ depending on the nature of the liver disease. Accurate assessment of symptoms by contemporary diagnostic modalities is essential for identifying patients at risk, for evaluating candidates for treatment, and prior to any invasive procedures. This review explores current perspectives within this field.

The Outcomes of Liver Transplantation in Severe Metabolic Dysfunction-Associated Steatotic Liver Disease Patients

The increasing prevalence of diabetes mellitus, obesity, and metabolic syndrome in the population can lead to metabolic dysfunction-associated steatohepatitis (MASH) and metabolic dysfunction-associated steatotic liver disease (MASLD). In Western industrialized countries, this has become a major problem with significant socioeconomic impacts. MASH is now a leading cause of liver transplantation (LT), especially in developed countries. However, the post-transplant outcomes of such patients are a major concern, and published data are limited and extremely variable. In this article, we discuss graft and patient survival after LT, complications, the recurrence of MASH, and MASH appearing de novo after transplantation. Recent studies suggest that patients with MASH have slightly worse short-term survival, potentially due to increased cardiovascular mortality. However, most studies found that longer-term outcomes for patients undergoing LT for MASH are similar or even better than those for other indications. Hepatocellular carcinoma due to MASH cirrhosis also has similar or even better outcomes after LT than other etiologies. In conclusion, we suggest questions and topics that require further research to enhance healthcare for this growing patient population.

Nonalcoholic Fatty Liver Disease Predicts Acute Kidney Injury Readmission in Heart Failure Hospitalizations: A Nationwide Analysis

Nonalcoholic fatty liver disease (NAFLD) has been associated with the progression of chronic kidney disease. However, limited data is available on its impact on acute kidney injury (AKI) in heart failure(HF) patients. All primary adult HF admissions from the national readmission database of 2016-2019 were identified. Admissions from July to December of each year were excluded to allow 6 months of follow-up. Patients were stratified according to the presence of NAFLD. Complex multivariate cox regression was used to adjust for confounders and calculate the adjusted hazard ratio. A total of 420,893 weighted patients admitted with HF were included in our cohort, of whom 780 had a secondary diagnosis of NAFLD. Patients with NAFLD were younger, more likely to be female, and had higher rates of obesity and diabetes mellitus. Both groups had similar rates of chronic kidney disease irrespective of the stage. NAFLD was associated with an increased risk of 6-month readmission with AKI (26.8% vs 16.6%, adjusted hazard ratio:1.44, 95% CI [1.14-1.82], P = 0.003). The mean time to AKI readmission was 150 ± 44 days. NAFLD was associated with a shorter mean time to readmission (145 ± 45 vs 155 ± 42 days, β =  -10 days, P = 0.044). Our study from a national database suggests that NAFLD is an independent predictor of 6-months readmission with AKI in patients admitted with HF. Further research is warranted to validate these findings.

Nonalcoholic fatty liver disease and hepatocellular carcinoma:Insights in epidemiology, pathogenesis, imaging, prevention and therapy

Hepatocellular carcinoma (HCC) is estimated to be the third leading cause of cancer-related mortality and is characterized by low survival rates. Nonalcoholic fatty liver disease (NAFLD) is emerging as a leading cause of HCC, whose rates are increasing, owing to the increasing prevalence of NAFLD. The pathogenesis of NAFLD-associated HCC is multifactorial: insulin resistance, obesity, diabetes and the low-grade hepatic inflammation, which characterizes NAFLD, seem to play key roles in the development and progression of HCC. The diagnosis of NAFLD-associated HCC is based on imaging in the presence of liver cirrhosis, preferably computerized tomography or magnetic resonance imaging, but liver biopsy for histological confirmation is usually required in the absence of liver cirrhosis. Some preventive measures have been recommended for NAFLD-associated HCC, including weight loss, cessation of even moderate alcohol drinking and smoking, as well as the use of metformin, statins and aspirin. However, these preventive measures are mainly based on observational studies, thus they need validation in trials of different design before introducing in clinical practice. The treatment of NAFLD should be tailored on an individual basis and should be ideally determined by a multidisciplinary team. In the last two decades, new medications, including tyrosine kinase inhibitors and immune checkpoints inhibitors, have improved the survival of patients with advanced HCC, but trials specifically designed for patients with NAFLD-associated HCC are scarce. The aim of this review was to overview evidence on the epidemiology and pathophysiology of NAFLD-associated HCC, then to comment on imaging tools for its appropriate screening and diagnosis, and finally to critically summarize the currently available options for its prevention and treatment.

Evolution of pretransplant cardiac risk factor burden and major adverse cardiovascular events in liver transplant recipients over time

Major adverse cardiovascular events (MACEs) are the leading cause of early (<1 y) complications after liver transplantation (LT). NASH, the leading indication for waitlisting for LT, is associated with high cardiac risk factor burden. The contemporary prevalence and temporal trends in pretransplant cardiac risk factor burden and post-LT MACE among LT recipients (LTRs) with and without NASH are unknown. The aim of this study was to evaluate (1) the evolution of post-LT cardiac risk factors in LTRs over time and (2) post-LT MACE over time, stratified by NASH status. This is a retrospective cohort of 1775 adult LTRs at a single transplant center (2003-2020). MACE was defined as death or hospitalization from myocardial infarction, revascularization, stroke, heart failure during the first post-LT year. Between 2003 and 2020, there was a significant increase in pre-LT NASH ( ptrend <0.05). There was also a significant increase in pre-LT obesity, atherosclerotic cardiovascular (CV) disease, and older age (≥65 y old) ( ptrend <0.05 for all). There was no significant change in the proportion of LTRs with diabetes, chronic kidney disease, or heart failure. Unexpectedly, there were no changes in the rate of post-LT MACE over the study period (-0.1% per year, ptrend =0.44). The lack of change in MACE despite an increase in CV risk factor prevalence may reflect advancement in the identification and management of CV risk factors in LTRs. With projected continued increase in cardiac risk burden and the proportion of patients transplanted for NASH, it is critical for LT programs to develop and implement quality improvement efforts to optimize CV care in LTRs.

Utility and prognostic value of diagnosing MAFLD in patients undergoing liver transplantation for alcohol-related liver disease

BACKGROUND

Recently, the term metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to replace non-alcoholic fatty liver disease (NAFLD). This concept enables diagnosing liver disease associated with metabolic dysfunction in patients with alcohol-related liver disease (ALD), a main indication for liver transplantation (LTx). We assessed MAFLD prevalence in ALD patients undergoing LTx and its prognostic value on post-LTx outcomes.

METHODS

We retrospectively analyzed all ALD patients transplanted at our center between 1990 and August 2020. MAFLD was diagnosed based on the presence or history of hepatic steatosis and a BMI > 25 or type II diabetes or ≥ 2 metabolic risk abnormalities at LTx. Overall survival and risk factors for recurrent liver and cardiovascular events were analyzed by Cox regression.

RESULTS

Of the 371 included patients transplanted for ALD, 255 (68.7%) had concomitant MAFLD at LTx. Median follow-up post-LTx was 72 months (IQR: 34.50-122). Patients with ALD-MAFLD were older at LTx (p = .001), more often male (p < .001) and more frequently had hepatocellular carcinoma (p < .001). No differences in perioperative mortality and overall survival were found. ALD-MAFLD patients had an increased risk of recurrent hepatic steatosis, irrespective of alcohol relapse, but no superimposed risk of cardiovascular events.

CONCLUSIONS

The co-presence of MAFLD at LTx for ALD is associated with a distinct patient profile and is an independent risk factor for recurrent hepatic steatosis. The use of MAFLD criteria in ALD patients might increase awareness and treatment of specific hepatic and systemic metabolic abnormalities before and after LTx.

Liver transplantation for non-alcoholic fatty liver disease: indications and post-transplant management

Non-alcoholic fatty liver disease (NAFLD) is currently the fastest growing indication to liver transplantation (LT) in Western Countries, both for end stage liver disease and hepatocellular carcinoma. NAFLD/non-alcoholic steatohepatitis (NASH) is often expression of a systemic metabolic syndrome; therefore, NAFLD/NASH patients require a multidisciplinary approach for a proper pre-surgical evaluation, which is important to achieve a post-transplant outcome comparable to that of other indications to LT. NAFLD/NASH patients are also at higher risk of post-transplant cardiovascular events, diabetes, dyslipidemia, obesity, renal impairment and recurrent NASH. Lifestyle modifications, included diet and physical activity, are key to improve survival and quality of life after transplantation. A tailored immunosuppressive regimen may be proposed in selected patients. Development of new drugs for the treatment of recurrent NASH is awaited.

Outcomes of Nonalcoholic Steatohepatitis After Liver Transplantation: An Updated Meta-Analysis and Systematic Review

BACKGROUND & AIMS

Nonalcoholic steatohepatitis (NASH) is the fastest growing indication of liver transplantation (LT) and is projected to be the leading cause of LT in the near future. The systemic pathogenesis of NASH increases risks of adverse clinical outcomes in patients with NASH receiving LT. Thus, this study aimed to conduct a time-dependent survival analysis between LT recipients with and without NASH using hazard ratios.

METHODS

A search was conducted on Medline and Embase databases for articles relating to LT outcomes for NASH recipients. A survival analysis was conducted of hazard ratios using the DerSimonian and Laird random-effects model with meta-regression. To account for censoring, survival data were reconstructed from published Kaplan-Meier curves and pooled to derive more accurate hazard estimates and all-cause mortality in NASH patients after LT. Pairwise meta-analysis was conducted to analyze secondary outcomes.

RESULTS

Fifteen studies involving 119,327 LT recipients were included in our analysis with a prevalence of NASH of 20.2% (95% CI, 12.9-30.2). The pooled 1-year, 5-year, and 10-year all-cause mortality in NASH patients after LT were 12.5%, 24.4%, and 37.9%, respectively. Overall survival was comparable between LT recipients for NASH vs non-NASH (hazard ratio, 0.910; 95% CI, 0.760 to 1.10; P = .34). Meta-regression showed that a higher model for end-stage liver disease score was associated with significantly worse overall survival in NASH compared with non-NASH after LT (95% CI, -0.0856 to -0.0181; P = .0026).

CONCLUSIONS

This study shows that patients undergoing LT for NASH cirrhosis have comparable complication rates, overall survival, and graft survival compared with non-NASH patients, although close monitoring may be indicated for those with higher model for end-stage liver disease scores.

Outcomes of Liver Transplantation in Patients with Preexisting Coronary Artery Disease

BACKGROUND

Advances in surgical and medical technology over the years has made liver transplantation possible for older and higher risk patients. Despite rigorous preoperative cardiac testing, cardiovascular events remain a major cause of death after orthotopic liver transplantation (OLT). However, there are little data on the outcomes of OLT in patients with preexisting coronary artery disease (CAD). This study aimed to compare all-cause and cardiovascular mortality of patients with and without history of CAD undergoing OLT.

METHODS

Six hundred ninety-three adult patients with cirrhosis underwent liver transplantation between July 2013 and December 2018 (female n = 243, male n = 450; median age 59).

RESULTS

During the study period of 5 y (median follow-up, 24.1 mo), 92 of 693 patients (13.3%) died. All-cause mortality in the CAD group was significantly higher than in the non-CAD group (26.7% versus 9.6%; P <0.01). Cardiovascular events accounted for 52.5% of deaths (n = 21) in patients with CAD compared with 36.5% (n = 19) in non-CAD patients. At 6 mo, patients with combined nonalcoholic steatohepatitis (NASH)/CAD had significantly worse survival than those with CAD or NASH alone ( P <0.01). After 6 mo, patients with CAD alone had similar survival to those with combined NASH/CAD.

CONCLUSIONS

Patients with preexisting CAD before liver transplantation are at higher risk of death from any cause, specifically cardiovascular-related death. This risk increases with coexisting NASH. The presence of NASH and CAD at the time of liver transplant should prompt the initiation of aggressive risk factor modification for patients with CAD.

Evaluation of liver transplant candidates with non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH) is anticipated to become the leading indication for liver transplantation (LT) in the United States in the near future. LT is indicated in patients with NASH-related cirrhosis who have medically refractory hepatic decompensation, synthetic dysfunction, and hepatocellular carcinoma (HCC) meeting certain criteria. The objective of LT evaluation is to determine which patient will derive the most benefit from LT with the least risk, thus maximizing the societal benefits of a limited resource. LT evaluation is a multidisciplinary undertaking involving several specialists, assessment tools, and diagnostic testing. Although the steps involved in LT evaluation are relatively similar across different liver diseases, patients with NASH-related cirrhosis have unique demographic and clinical features that affect transplant outcomes and influence their LT evaluation. LT candidates with NASH should be assessed for metabolic syndrome and obesity, malnutrition and sarcopenia, frailty, and cardiovascular disease. Interventions that treat cardiometabolic co-morbidities and improve patients' nutrition and functionality should be considered in order to improve patient outcomes in the waitlist and after LT.

Clinical evidence of outcomes following liver transplantation in patients with nonalcoholic steatohepatitis: An updated meta-analysis and systematic review

OBJECTIVE

Nonalcoholic steatohepatitis (NASH) is a dramatically growing indication for liver transplantation (LT) worldwide and the posttransplant outcomes of NASH patients are currently under intensive investigation. This quantitative meta-analysis aimed to update the clinical evidence on outcomes of transplanted patients with NASH.

METHODS

We performed a systematic review and meta-analysis of studies (published up to September 15, 2021) that focused on LT outcomes for NASH versus non-NASH patients. Random-effect meta-analysis was conducted to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses based on crucial baseline clinical characteristics and leave-one-out sensitivity analyses were conducted to assess the robustness of the pooled results. Meta-regression was used to evaluate study-level demographic, clinical, and biochemical characteristics to identify potential confounders affecting patient survival.

RESULTS

Twenty-two non-randomized comparative studies with 1,538 NASH and 6,014 non-NASH patients were included. 1- (OR, 0.94; 95% CI, 0.77-1.14), 3- (OR, 0.82; 95% CI, 1.00-1.22), and 5- (OR, 1.05; 95% CI, 0.84-1.31) year patient survival was equivalent between NASH and non-NASH recipients. NASH patients were associated with similar cardiovascular mortality (OR, 1.36; 95% CI, 0.89-2.09) and retransplantation rates (OR, 0.69; 95% CI, 1.03-1.53), lower graft failure-related mortality (OR, 0.11; 95% CI, 0.29-0.74), but higher sepsis-related mortality (OR, 1.53; 95% CI, 1.13-2.06). Meta-regression revealed that a higher proportion of patients with hepatocellular carcinoma (HCC) were associated with significantly superior overall patient survival at 1 (P = 0.044), 3 (P = 0.035) and 5 (P = 0.049) years after LT in NASH compared with non-NASH.

CONCLUSIONS

This study shows no difference in posttransplant survival between NASH and non-NASH patients. Carefully selected patients with NASH-related HCC may benefit from LT. NASH recipients should be managed with caution posttransplant, especially regarding the potentially high risk of sepsis-related death.

Metabolic-associated Fatty Liver Disease (MAFLD): A Multi-systemic Disease Beyond the Liver

Nonalcoholic fatty liver disease (NAFLD) is a multisystemic clinical condition that presents with a wide spectrum of extrahepatic manifestations, such as obesity, type 2 diabetes mellitus, metabolic syndrome, cardiovascular diseases, chronic kidney disease, extrahepatic malignancies, cognitive disorders, and polycystic ovarian syndrome. Among NAFLD patients, the most common mortality etiology is cardiovascular disorders, followed by extrahepatic malignancies, diabetes mellitus, and liver-related complications. Furthermore, the severity of extrahepatic diseases is parallel to the severity of NAFLD. In clinical practice, awareness of the associations of concomitant diseases is of major importance for initiating prompt and timely screening and multidisciplinary management of the disease spectrum. In 2020, a consensus from 22 countries redefined the disease as metabolic (dysfunction)-associated fatty liver disease (MAFLD), which resulted in the redefinition of the corresponding population. Although the patients diagnosed with MAFLD and NAFLD mostly overlap, the MAFLD and NAFLD populations are not identical. In this review, we compared the associations of key extrahepatic diseases between NAFLD and MAFLD.

Cardiovascular manifestation of end-stage liver disease and perioperative echocardiography for liver transplantation: anesthesiologist’s view

Liver transplantation (LT) is the curative therapy for decompensated cirrhosis. However, anesthesiologists can find it challenging to manage patients undergoing LT due to the underlying pathologic conditions of patients with end-stage liver disease and the high invasiveness of the procedure, which is frequently accompanied by massive blood loss. Echocardiography is a non-invasive or semi-invasive imaging tool that provides real-time information about the structural and functional status of the heart and is considered to be able to improve outcomes by enabling accurate and detailed assessments. This article reviews the pathophysiologic changes of the heart accompanied by cirrhosis that mainly affect hemodynamics. We also present a comparative review of the diagnostic criteria for cirrhotic cardiomyopathy published by the World Congress of Gastroenterology in 2005 and the Cirrhotic Cardiomyopathy Consortium in 2019. This article discusses the conditions that could affect hemodynamic stability and postoperative outcomes, such as coronary artery disease, left ventricular outflow tract obstruction, portopulmonary hypertension, hepatopulmonary syndrome, pericardial effusion, cardiac tamponade, patent foramen ovale, and ascites. Finally, we cover a number of intraoperative factors that should be considered, including intraoperative blood loss, rapid reaccumulation of ascites, manipulation of the inferior vena cava, post-reperfusion syndrome, and adverse effects of excessive fluid infusion and transfusion. This article aimed to summarize the cardiovascular manifestations of cirrhosis that can affect hemodynamics and can be evaluated using perioperative echocardiography. We hope that this article will provide information about the hemodynamic characteristics of LT recipients and stimulate more active use of perioperative echocardiography.

Introduction of a standardized protocol for cardiac risk assessment in candidates for liver transplant - A retrospective cohort analysis

INTRODUCTION

Recommendations on non-invasive imaging to assess pre-operative cardiac risk among liver transplant candidates vary amongst societal guidelines and individual institutional practices. In 2018, a standardized pre-transplant coronary evaluation protocol was established at Beth Israel Deaconess Medical Center, Boston MA, to ensure appropriate and consistent pre-operative testing was performed.

METHODS

All patients who underwent liver transplant evaluation between January 1st, 2016 and December 31st, 2019, were retrospectively analyzed and divided into three cohorts; before the introduction of the protocol (prior to 2018), initial protocol favoring invasive coronary angiography (ICA) (2018), and amended protocol favoring coronary computed tomography angiography (CCTA) (post-2018). We described clinical characteristics, candidacy for transplant, and cardiovascular complications during follow-up. As an unadjusted exploratory analysis, the Cochran-Armitage Exact Trend Test was used to examine univariate differences across time.

RESULTS

A total of 462 patients underwent liver transplant evaluation during the study period. Among these, 218 (47.2%) patients underwent stress test, 50 (10.8%) underwent CCTA, and 68 (14.8%) underwent ICA. Across the three time periods, there was an increase in the proportion of CCTAs performed (3%, 6.3%, and 26.3% respectively; p <0.001) and proportion of patients diagnosed with obstructive CAD using CCTA (0%, 30%, and 51.4% respectively; p = 0.04). There was no significant difference in post-transplant cardiac complications among patients evaluated before 2018, during 2018, and after 2018 (5.9% vs. 5.6 vs. 6.0%; p=1.0).

CONCLUSION

Our findings suggest it is reasonable to shift practice to a less invasive approach utilizing CCTA or nuclear stress testing when assessing liver transplant candidates at increased cardiovascular risk.

Donor-derived cell-free DNA levels predict graft injury in liver transplant recipients

Donor-derived cell-free DNA (dd-cfDNA) has been evaluated as a rejection marker in organ transplantation. This study sought to assess the utility of dd-cfDNA to diagnose graft injury in liver transplant recipients (LTR) and as a predictive biomarker prior to different causes of graft dysfunction. Plasma from single and multicenter LTR cohorts was analyzed for dd-cfDNA. Phenotypes of treated biopsy-proven acute rejection (AR, N = 57), normal function (TX, N = 94), and acute dysfunction no rejection (ADNR; N = 68) were divided into training and test sets. In the training set, dd-cfDNA was significantly different between AR versus TX (AUC 0.95, 5.3% cutoff) and AR versus ADNR (AUC 0.71, 20.4% cutoff). Using these cutoffs in the test set, the accuracy and NPV were 87% and 100% (AR vs. TX) and 66.7% and 87.8% (AR vs. ADNR). Blood samples collected serially from LTR demonstrated incremental elevations in dd-cfDNA prior to the onset of graft dysfunction (AR > ADNR), but not in TX. Dd-cfDNA also decreased following treatment of rejection. In conclusion, the serial elevation of dd-cfDNA identifies pre-clinical graft injury in the context of normal liver function tests and is greatest in rejection. This biomarker may help detect early signs of graft injury and rejection to inform LTR management strategies.

NAFLD-driven HCC: Safety and efficacy of current and emerging treatment options

In light of a global rise in obesity and type 2 diabetes, non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) represent an increasingly important underlying aetiology of hepatocellular carcinoma (HCC). HCCs arising from lipotoxicity-mediated chronic inflammation are characterised by several unique features: in contrast to virally driven HCC, up to 50% of NAFLD-HCC occurs in patients without cirrhosis and annual HCC incidence is comparatively low, complicating current surveillance strategies. On average, patients are older and are more frequently diagnosed at an advanced stage. While locoregional treatments are probably equally effective regardless of HCC aetiology, the picture is less clear for systemic therapy. Tyrosine kinase inhibitors are probably equally effective, while there have been initial signals that immune checkpoint inhibitors may be less effective in NAFLD-HCC than in viral HCC. Current international clinical practice guidelines for HCC do not consider aetiology, as there are insufficient data to draw specific conclusions or to recommend aetiology-specific modifications to the current management of patients with HCC. However, in light of the growing relevance of NAFLD-HCC, future clinical trials should assess whether HCC aetiology - and NAFLD/NASH in particular - influence the safety and efficacy of a given treatment.

Hypercoagulability in Patients with Non-Alcoholic Fatty Liver Disease (NAFLD): Causes and Consequences

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, and it is anticipated that it could become even more prevalent in parallel with an increase in the incidence of metabolic diseases closely related to NAFLD, such as obesity, type II diabetes, dyslipidemia, and arterial hypertension. In addition to liver impairment, NAFLD is associated with cardiovascular diseases. Fibrosis, atherosclerosis, and venous thrombosis are basically the pathogenic mechanisms behind these clinical manifestations, and all are plausibly associated with hypercoagulability that may, in turn, develop because of an imbalance of pro- vs. anticoagulants and the presence of such procoagulant molecular species as microvesicles, neutrophil extracellular traps (NETs), and inflammation. The assessment of hypercoagulability by means of thrombin generation is a global procedure that mimics the coagulation process occurring in vivo much better than any other coagulation test, and is considered to be the best candidate laboratory tool for assessing, with a single procedure, the balance of coagulation in NAFLD. In addition to defining the state of hypercoagulability, the assessment of thrombin generation could also be used to investigate, in clinical trials, the best approach (therapeutic and/or lifestyle changes) for minimizing hypercoagulability and, hence, the risk of cardiovascular diseases, progression to atherosclerosis, and liver fibrosis in patients with NAFLD.

Diagnosis and Management of Cirrhotic Cardiomyopathy

BACKGROUND

Cirrhotic cardiomyopathy refers to the structural and functional changes in the heart leading to either impaired systolic, diastolic, electrocardiographic, and neurohormonal changes associated with cirrhosis and portal hypertension. Cirrhotic cardiomyopathy is present in 50% of patients with cirrhosis and is clinically seen as impaired contractility, diastolic dysfunction, hyperdynamic circulation, and electromechanical desynchrony such as QT prolongation. In this review, we will discuss the cardiac physiology principles underlying cirrhotic cardiomyopathy, imaging techniques such as cardiac magnetic resonance imaging and scintigraphy, cardiac biomarkers, and newer echocardiographic techniques such as tissue Doppler imaging and speckle tracking, and emerging treatments to improve outcomes.

METHODS

We reviewed available literature from MEDLINE for randomized controlled trials, cohort studies, cross-sectional studies, and real-world outcomes using the search terms "cirrhotic cardiomyopathy," "left ventricular diastolic dysfunction," "heart failure in cirrhosis," "liver transplantation," and "coronary artery disease".

RESULTS

Cirrhotic cardiomyopathy is associated with increased risk of complications such as hepatorenal syndrome, refractory ascites, impaired response to stressors including sepsis, bleeding or transplantation, poor health-related quality of life and increased morbidity and mortality. The evaluation of cirrhotic cardiomyopathy should also guide the feasibility of procedures such as transjugular intrahepatic portosystemic shunt, dose titration protocol of betablockers, and liver transplantation. The use of targeted heart rate reduction is of interest to improve cardiac filling and improve the cardiac output using repurposed heart failure drugs such as ivabradine. Liver transplantation may also reverse the cirrhotic cardiomyopathy; however, careful cardiac evaluation is necessary to rule out coronary artery disease and improve cardiac outcomes in the perioperative period.

CONCLUSION

More data are needed on the new diagnostic criteria, molecular and biochemical changes, and repurposed drugs in cirrhotic cardiomyopathy. The use of advanced imaging techniques should be incorporated in clinical practice.

How will NAFLD change the liver transplant landscape in the 2020s?

Liver steatosis is the hepatic manifestation of the metabolic syndrome, and is now the leading cause of chronic liver disease worldwide. The treatment of metabolic cirrhosis with liver failure and/or hepatocellular carcinoma is liver transplantation (LT). During the past decade, metabolic cirrhosis represented an increasing cause for LT, especially in the United States. At listing, patients with metabolic cirrhosis are older, with numerous cardiovascular (CV) and renal comorbidities, and this requires multidisciplinary pre-transplant assessment. After LT, 5-year survival is similar to other indications. The leading causes of death are infectious, cancers and CV. The recurrence of the initial disease is very frequent, and a significant part of the patients progress towards graft cirrhosis. No specific immunosuppressive regimen is recommended, but the toxicity profiles must probably be taken into account. In these patients, the only etiological treatment is that of obesity, in the absence of specific therapy for non-alcoholic steatohepatitis. The place of bariatric surgery has to be defined, probably sleeve gastrectomy, in a stable patient, 6-12 months after LT.

De novo and recurrence of metabolic dysfunction-associated fatty liver disease after liver transplantation

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new acronym adopted from the consensus of international experts. Given the increasing prevalence of MAFLD in pre-transplant settings, de novo and recurrent graft steatosis/MAFLD are common in post-transplant settings. The impact of graft steatosis on long-term outcomes is unclear. The current knowledge of incidence rate, risk factors, diagnosis, long-term outcomes, and management of graft steatosis (both de novo and recurrent) is discussed in this review.

The comparative and added prognostic value of biomarkers to the Revised Cardiac Risk Index for preoperative prediction of major adverse cardiac events and all-cause mortality in patients who undergo noncardiac surgery

BACKGROUND

The Revised Cardiac Risk Index (RCRI) is a widely acknowledged prognostic model to estimate preoperatively the probability of developing in-hospital major adverse cardiac events (MACE) in patients undergoing noncardiac surgery. However, the RCRI does not always make accurate predictions, so various studies have investigated whether biomarkers added to or compared with the RCRI could improve this.

OBJECTIVES

Primary: To investigate the added predictive value of biomarkers to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Secondary: To investigate the prognostic value of biomarkers compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Tertiary: To investigate the prognostic value of other prediction models compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery.

SEARCH METHODS

We searched MEDLINE and Embase from 1 January 1999 (the year that the RCRI was published) until 25 June 2020. We also searched ISI Web of Science and SCOPUS for articles referring to the original RCRI development study in that period.

SELECTION CRITERIA

We included studies among adults who underwent noncardiac surgery, reporting on (external) validation of the RCRI and: - the addition of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of the RCRI to other models. Besides MACE, all other adverse outcomes were considered for inclusion.

DATA COLLECTION AND ANALYSIS

We developed a data extraction form based on the CHARMS checklist. Independent pairs of authors screened references, extracted data and assessed risk of bias and concerns regarding applicability according to PROBAST. For biomarkers and prediction models that were added or compared to the RCRI in ≥ 3 different articles, we described study characteristics and findings in further detail. We did not apply GRADE as no guidance is available for prognostic model reviews.

MAIN RESULTS

We screened 3960 records and included 107 articles.   Over all objectives we rated risk of bias as high in ≥ 1 domain in 90% of included studies, particularly in the analysis domain. Statistical pooling or meta-analysis of reported results was impossible due to heterogeneity in various aspects: outcomes used, scale by which the biomarker was added/compared to the RCRI, prediction horizons and studied populations.  Added predictive value of biomarkers to the RCRI Fifty-one studies reported on the added value of biomarkers to the RCRI. Sixty-nine different predictors were identified derived from blood (29%), imaging (33%) or other sources (38%). Addition of NT-proBNP, troponin or their combination improved the RCRI for predicting MACE (median delta c-statistics: 0.08, 0.14 and 0.12 for NT-proBNP, troponin and their combination, respectively). The median total net reclassification index (NRI) was 0.16 and 0.74 after addition of troponin and NT-proBNP to the RCRI, respectively. Calibration was not reported. To predict myocardial infarction, the median delta c-statistic when NT-proBNP was added to the RCRI was 0.09, and 0.06 for prediction of all-cause mortality and MACE combined. For BNP and copeptin, data were not sufficient to provide results on their added predictive performance, for any of the outcomes. Comparison of the predictive value of biomarkers to the RCRI  Fifty-one studies assessed the predictive performance of biomarkers alone compared to the RCRI. We identified 60 unique predictors derived from blood (38%), imaging (30%) or other sources, such as the American Society of Anesthesiologists (ASA) classification (32%). Predictions were similar between the ASA classification and the RCRI for all studied outcomes. In studies different from those identified in objective 1, the median delta c-statistic was 0.15 and 0.12 in favour of  BNP and NT-proBNP alone, respectively, when compared to the RCRI, for the prediction of MACE. For C-reactive protein, the predictive performance was similar to the RCRI. For other biomarkers and outcomes, data were insufficient to provide summary results. One study reported on calibration and none on reclassification. Comparison of the predictive value of other prognostic models to the RCRI   Fifty-two articles compared the predictive ability of the RCRI to other prognostic models. Of these, 42% developed a new prediction model, 22% updated the RCRI, or another prediction model, and 37% validated an existing prediction model. None of the other prediction models showed better performance in predicting MACE than the RCRI. To predict myocardial infarction and cardiac arrest, ACS-NSQIP-MICA had a higher median delta c-statistic of 0.11 compared to the RCRI. To predict all-cause mortality, the median delta c-statistic was 0.15 higher in favour of ACS-NSQIP-SRS compared to the RCRI. Predictive performance was not better for CHADS₂, CHA₂DS₂-VASc, R₂CHADS₂, Goldman index, Detsky index or VSG-CRI compared to the RCRI for any of the outcomes. Calibration and reclassification were reported in only one and three studies, respectively.

AUTHORS' CONCLUSIONS

Studies included in this review suggest that the predictive performance of the RCRI in predicting MACE is improved when NT-proBNP, troponin or their combination are added. Other studies indicate that BNP and NT-proBNP, when used in isolation, may even have a higher discriminative performance than the RCRI. There was insufficient evidence of a difference between the predictive accuracy of the RCRI and other prediction models in predicting MACE. However, ACS-NSQIP-MICA and ACS-NSQIP-SRS outperformed the RCRI in predicting myocardial infarction and cardiac arrest combined, and all-cause mortality, respectively. Nevertheless, the results cannot be interpreted as conclusive due to high risks of bias in a majority of papers, and pooling was impossible due to heterogeneity in outcomes, prediction horizons, biomarkers and studied populations. Future research on the added prognostic value of biomarkers to existing prediction models should focus on biomarkers with good predictive accuracy in other settings (e.g. diagnosis of myocardial infarction) and identification of biomarkers from omics data. They should be compared to novel biomarkers with so far insufficient evidence compared to established ones, including NT-proBNP or troponins. Adherence to recent guidance for prediction model studies (e.g. TRIPOD; PROBAST) and use of standardised outcome definitions in primary studies is highly recommended to facilitate systematic review and meta-analyses in the future.

Latin American Association for the study of the liver (ALEH) practice guidance for the diagnosis and treatment of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) currently represents an epidemic worldwide. NAFLD is the most frequently diagnosed chronic liver disease, affecting 20-30% of the general population. Furthermore, its prevalence is predicted to increase exponentially in the next decades, concomitantly with the global epidemic of obesity, type 2 diabetes mellitus (T2DM), and sedentary lifestyle. NAFLD is a clinical syndrome that encompasses a wide spectrum of associated diseases and hepatic complications such as hepatocellular carcinoma (HCC). Moreover, this disease is believed to become the main indication for liver transplantation in the near future. Since NAFLD management represents a growing challenge for primary care physicians, the Asociación Latinoamericana para el Estudio del Hígado (ALEH) has decided to organize this Practice Guidance for the Diagnosis and Treatment of Non-Alcoholic Fatty Liver Disease, written by Latin-American specialists in different clinical areas, and destined to general practitioners, internal medicine specialists, endocrinologists, diabetologists, gastroenterologists, and hepatologists. The main purpose of this document is to improve patient care and awareness of NAFLD. The information provided in this guidance may also be useful in assisting stakeholders in the decision-making process related to NAFLD. Since new evidence is constantly emerging on different aspects of the disease, updates to this guideline will be required in future.

Management of Patients With Non-alcoholic Steatohepatitis Undergoing Liver Transplantation: Considerations for the Anesthesiologist

Non-alcoholic fatty liver disease (NAFLD) currently affects more than 25% of the world population and is rising. NAFLD can progress to non-alcoholic steatohepatitis that is associated with hepatic inflammation and fibrosis and can result in cirrhosis with subsequent liver failure. Non-alcoholic steatohepatitis (NASH) has now emerged as one of the leading etiologies for a liver transplant among adults in the United States. Given the rising incidence of liver transplants in patients with NASH-related cirrhosis, it is essential for anesthesiologists to be familiar with this condition as well as with NASH-related comorbidities and perioperative complications. Not only is NASH linked to metabolic syndrome, but it also is independently associated with cardiovascular disease, renal and thyroid dysfunction, obstructive sleep apnea (OSA), and a hypercoagulable state. The association with these conditions can affect the perioperative outcome of these patients, particularly because of increased mortality from major adverse cardiovascular events and sepsis. In order to decrease the perioperative morbidity and mortality of patients with NASH undergoing a liver transplant, a multidisciplinary approach to their perioperative management is essential, along with careful preoperative evaluation and aggressive intraoperative and postoperative monitoring. The focus of this review article is to provide a comprehensive overview of challenges associated with liver transplants in patients with NASH and to provide suggestions for appropriate patient selection and perioperative management.

Prognostic Value of Computed Tomographic Coronary Angiography for Long-Term Major Adverse Cardiac Events after Liver Transplantation

Computed tomographic coronary angiography (CTCA) has prognostic value for early major adverse cardiac events (MACEs) after liver transplantation. However, the association between CTCA and long-term MACEs in liver transplant (LT) recipients remains unknown. We evaluated the association between CTCA and long-term MACEs within 5 years after living donor liver transplantation (LDLT). A total of 628 LDLT recipients who underwent CTCA were analyzed between 2010 and 2012. MACEs were investigated within 5 years after LDLT. The factors associated with long-term MACEs in transplant recipients were evaluated. Only 48 (7.6%) patients developed MACEs. In the Fine and Gray competing risk regression, a coronary artery calcium score (CACS) of >400 combined with obstructive coronary artery disease (CAD) (subdistribution hazard ratio: 5.01, 95% confidence interval: 2.37–10.58, p < 0.001), age (1.05, 1.01–1.10, p = 0.018), diabetes mellitus (2.43, 1.37–4.29, p = 0.002), dyslipidemia (2.45, 1.23–4.70, p = 0.023), and creatinine (1.19, 1.08–1.30, p < 0.001) were independently associated with long-term MACEs. CACS (>400) combined with obstructive CAD may be associated with MACEs within 5 years after LDLT, suggesting the importance of preoperative noninvasive CTCA in LT recipients. The evaluation of coronary artery stenosis on CTCA combined with CACS may have a prognostic value for long-term MACEs in LT recipients.

Cardiac Risk Assessment in Liver Transplant Candidates: Current Controversies and Future Directions

In the changing landscape of liver transplantation (LT), we are now evaluating older and sicker patients with more cardiovascular comorbidities, and the spectrum of cardiovascular disease is uniquely physiologically impacted by end-stage liver disease. Cardiac complications are now the leading cause of morbidity and mortality in LT recipients, and the pretransplant risk is exacerbated immediately during the transplant operation and continues long term under the umbrella of immunosuppression. Accurate risk estimation of cardiac complications before LT is paramount to guide allocation of limited health care resources and to improve both short-term and long-term clinical outcomes for patients. Current screening and diagnostic testing are limited in their capacity to accurately identify early coronary disease and myocardial dysfunction in persons with end-stage liver disease physiology. Furthermore, a number of testing modalities have not been evaluated in patients with end-stage liver disease. As a result, there is wide variation in cardiac risk assessment practices across transplant centers. In this review, we propose a definition for defining cardiac events in LT, evaluate the current evidence for surgery-related, short-term and long-term cardiac risk assessment in LT candidates, propose an evidence-based testing algorithm, and highlight specific gaps in knowledge and current controversies, identifying areas for future research.

Liver-Related and Cardiovascular Outcome of Patients Transplanted for Nonalcoholic Fatty Liver Disease: A European Single-Center Study

BACKGROUND

The increasing rate of liver transplantation (LT) for nonalcoholic fatty liver disease (NAFLD) raises concerns on cardiovascular morbidity and mortality after LT in these patients.

METHODS

We collected variables regarding the presence of metabolic risk factors, NAFLD recurrence, cardiovascular morbidity, and overall survival at time of listing and after LT of 112 patients with NAFLD and a control group of 120 patients with hepatitis C (HCV).

RESULTS

Metabolic syndrome and cardiovascular morbidity component rates (24.1% vs 12.5%) at the time of LT listing were higher in patients with NAFLD compared with patients with HCV (for all, P < .0390). Median follow-up after LT was 5.6 years in patients with NAFLD vs 13.5 years in patients with HCV (P = .0009). There was no difference in 6-weeks postoperative mortality (1.7% vs 2.5%) (P =1.0000). Metabolic syndrome components after LT were more frequent in patients with NAFLD than in patients with HCV (for all, P < .0008). The incidence of NAFLD 5 years after LT was higher in patients transplanted for NAFLD compared with HCV (43.5% vs 4.2%) (P < .0001). Patients with recurrent NAFLD more often had myocardial infarction compared with those without recurrence (8.3% vs 0%) (P = .0313). Five years after LT, cardiovascular morbidity was more frequent in the NAFLD group than in the HCV group (12.8% vs 9.3%) (P = .0256), whereas no difference in overall survival was observed.

CONCLUSION

LT for NAFLD is associated with satisfactory 5-year outcomes; however, our data underscore the need for close monitoring and aggressive management of cardiovascular risk factors in these patients.

Non-alcoholic fatty liver disease: a review of epidemiology, risk factors, diagnosis and management

Due to the rising prevalence of obesity and type II diabetes mellitus, non-alcoholic fatty liver disease is becoming the leading cause of chronic liver disease in the Western world. In some patients, simple steatosis can result in non-alcoholic steatohepatitis which over time can lead to liver cirrhosis and its associated sequelae, including hepatocellular carcinoma. Early identification and management of patients at risk with intensive dietary and lifestyle modification are essential to prevent the development of advanced liver disease and its complications. In this review, we will discuss the epidemiology of non-alcoholic fatty liver disease, pathogenesis, diagnosis, management and surveillance strategies to offset the morbidity and mortality of this disease, as well as liver and non-liver-related complications.

Machine Learning Models to Predict Major Adverse Cardiovascular Events After Orthotopic Liver Transplantation: A Cohort Study

OBJECTIVE

To develop machine learning models that can predict post-transplantation major adverse cardiovascular events (MACE), all-cause mortality, and cardiovascular mortality in patients undergoing liver transplantation (LT).

DESIGN

Retrospective cohort study.

SETTING

High-volume tertiary care center.

PARTICIPANTS

The study comprised 1,459 consecutive patients undergoing LT between January 2008 and December 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

MACE, all-cause mortality, and cardiovascular mortality were modeled using logistic regression, least absolute shrinkage and selection surgery regression, random forests, support vector machine, and gradient-boosted modeling (GBM). All models were built by splitting data into training and testing cohorts, and performance was assessed using five-fold cross-validation based on the area under the receiver operating characteristic curve and Harrell's C statistic. A total of 1,459 patients were included in the final cohort; 1,425 (97.7%) underwent index transplantation, 963 (66.0%) were female, the median age at transplantation was 57 (11-70) years, and the median Model for End-Stage Liver Disease score was 20 (6-40). Across all outcomes, the GBM model XGBoost achieved the highest performance, with an area under the receiver operating curve of 0.71 (95% confidence interval [CI] 0.63-0.79) for MACE, a Harrell's C statistic of 0.64 (95% CI 0.57-0.73) for overall survival, and 0.72 (95% CI 0.59-0.85) for cardiovascular mortality over a mean follow-up of 4.4 years. Examination of Shapley values for the GBM model revealed that on the cohort-wide level, the top influential factors for postoperative MACE were age at transplantation, diabetes, serum creatinine, cirrhosis caused by nonalcoholic steatohepatitis, right ventricular systolic pressure, and left ventricular ejection fraction.

CONCLUSION

Machine learning models developed using data from a tertiary care transplantation center achieved good discriminant function in predicting post-LT MACE, all-cause mortality, and cardiovascular mortality. These models can support clinicians in recipient selection and help screen individuals who may be at elevated risk for post-transplantation MACE.

Cardiovascular involvement after liver transplantation: role of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis

Patients submitted to liver transplantation (LT) are exposed to high risk of cardiovascular (CV) complications which are the main determinants of both short-term and long-term morbidity and mortality in LT. Non-alcoholic fatty liver disease (NAFLD) is a very frequent condition in general population and is associated with a high risk of cardiovascular disease (CVD) which represents the first cause of death of these patients. NAFLD is predicted to become the first indication to LT and nowadays is also frequently detected in patients submitted to LT for other indications. Thus, the risk of CVD in patients submitted to LT is forecasted to increase in the next years. In this review the extent of CV involvement in patients submitted to LT and the role of NAFLD, either recurring after transplantation or as de novo presentation, in increasing CV risk is analysed. The risk of developing metabolic alterations, including diabetes, hypertension, dyslipidemia and weight gain, all manifestations of metabolic syndrome, occurring in the first months after LT, is depicted. The different presentations of cardiac involvement, represented by early atherosclerosis, coronary artery disease, heart failure and arrhythmias in patients with NAFLD submitted to LT is described. In addition, the tools to detect cardiac alterations either before or after LT is reported providing the possibility for an early diagnosis of CVD and an early therapy able to reduce morbidity and mortality for these diseases. The need for long-term concerted multidisciplinary activity with dietary counseling and exercise combined with drug treatment of all manifestations of metabolic syndrome is emphasized.

Hepatocellular carcinoma in non-alcoholic fatty liver disease-a review of an emerging challenge facing clinicians

Importance

Non-alcoholic fatty liver disease (NAFLD) is a rapidly growing cause of chronic liver disease and is becoming a leading cause of hepatocellular carcinoma (HCC) in many developed countries. This presents major challenges for the surveillance, diagnosis and treatment of HCC.

Objective

To discuss the clinical challenges faced by clinicians in managing the rising number of NAFLD-HCC cases.

Evidence Review

MEDLINE, PubMed and Embase databases were searched using the keywords; NAFLD, HCC, surveillance, hepatectomy, liver transplantation, percutaneous ablation, transarterial chemoembolization (TACE), selective internal radiotherapy treatment (SIRT) and sorafenib. Relevant clinical studies were included.

Findings

Current HCC surveillance programmes are inadequate because they only screen for HCC in patients with cirrhosis, whereas in NAFLD a significant proportion of HCC develops in the absence of cirrhosis. Consequently NAFLD patients often present with a more advanced stage of HCC, with a poorer prognosis. NAFLD-HCC patients also tend to be older and to have more co-morbidities compared to HCC of other etiologies. This limits the use of curative treatments such as liver resection and orthotopic liver transplantation (OLT). Evidence suggests that although NAFLD-HCC patients who undergo liver resection or OLT have worse perioperative and short-term outcomes, overall long-term survival is comparable to HCC of other etiologies. This highlights the importance of careful patient selection, pre-habilitation and perioperative planning for NAFLD-HCC patients being considered for surgical treatment. Careful consideration is also important for non-surgical treatments, although the evidence supporting treatment selection is frequently lacking, as these patients tend to be poorly represented in clinical trials. Locoregional therapies such as percutaneous ablation and TACE may be less well tolerated and less effective in NAFLD patients with obesity or diabetes. The tyrosine kinase inhibitor sorafenib may also be less effective.

Conclusions and Relevance

This review highlights how international guidelines, for which NAFLD traditionally has made up a small part of the evidence base, may not be appropriate for all NAFLD-HCC patients. Future guidelines need to reflect the changing landscape of HCC, by making specific recommendations for the management of NAFLD-HCC.

Cardiac and Pulmonary Vascular Risk Stratification in Liver Transplantation

Cardiovascular disease complications are the leading cause of early (short-term) mortality among liver transplant recipients. The increasingly older candidate pool has multiple comorbidities necessitating cardiac and pulmonary vascular disease risk stratification of patients for optimal allocation of scarce donor livers. Arrhythmias, heart failure, stroke, and coronary artery disease are common pretransplant cardiovascular comorbidities and contribute to cardiovascular complications after liver transplant. Valvular heart disease and portopulmonary hypertension present intraoperative challenges during liver transplant surgery. The Cardiovascular Risk in Orthotopic Liver Transplantation score estimates the risk of cardiovascular complications in liver transplant candidates within the first year after transplant.

Metabolic syndrome following liver transplantation in nonalcoholic steatohepatitis

Metabolic syndrome is a major clinical disorder involving metabolic dysregulation characterized clinically with features of central obesity, insulin resistance (IR), type 2 diabetes, hypertension, and dyslipidemia. Metabolic syndrome is strongly associated with the rising prevalence nonalcoholic steatohepatitis, a leading indication for orthotopic liver transplantation in the Western world. The presence or recurrence of metabolic syndrome following liver transplantation can contribute to the development and recurrence of nonalcoholic fatty liver disease (NAFLD) in the liver allograft. In this review, we discuss the endogenous and exogenous drivers of post-transplant metabolic syndrome, role of chronic immunosuppression, and the prevalence and clinical significant of post-transplant metabolic syndrome on nonalcoholic steatohepatitis.

Association of TCF7L2 rs7903146 Gene Polymorphism with the Risk of NAFLD and CAD in the Chinese Han Population

Background and Aims: Coronary artery disease (CAD) is a major cause of morbidity and mortality in patients with non-alcoholic fatty liver disease (NAFLD). Previous studies have suggested that TCF7L2 rs7903146 was related to the risk of developing NAFLD but the conclusions are not consistent and no related study has been conducted in Chinese populations. The aim of this study was to investigate the association between TCF7L2 rs7903146 and the risk of developing NAFLD and CAD in a Chinese Han population. Methods: TCF7L2 rs7903146 genotypes were measured by the MALDI-TOF-MS from 143 NAFLD patients, 159 CAD patients, 131 NAFLD + CAD patients, and 212 healthy controls. The demographic data and serum lipid profiles of all subjects were collected. The distributions of genotype and allele frequency in each group were also tested. Logistic regression was used to investigate the risk of TCF7L2 rs7903146 with NAFLD and CAD. All statistical analyses were conducted using SPSS 23.0. Results: There were no significant differences in the distributions of TCF7L2 rs7903146 genotype and allele frequency in each of the two groups, and the TCF7L2 rs7903146 CT + TT genotype did not increase the risk of developing NAFLD, CAD, and NAFLD + CAD. Except for body mass index in the control group, the differences of clinical parameters between the TCF7L2 rs7903146 T allele carriers and non-carriers in each group were not significant. In the non-obese group, the TCF7L2 rs7903146 CT + TT genotype was a protective factor for the development of NAFLD in the non-obese subjects (odds ratio=0.359, 95% confidence interval: 0.134-0.961, p = 0.041). Conclusions: TCF7L2 rs7903146 was not associated with the risk of developing NAFLD, CAD, and NAFLD + CAD in the Chinese Han population. In the non-obese population, the TCF7L2 rs7903146 CT + TT genotype was a protective factor against the development of NAFLD.

Metabolic associated fatty liver disease: Addressing a new era in liver transplantation

Metabolic associated fatty liver disease (MAFLD), previously termed non-alcoholic fatty liver disease, is the leading global cause of liver disease and is fast becoming the most common indication for liver transplantation. The recent change in nomenclature to MAFLD refocuses the conceptualisation of this disease entity to its metabolic underpinnings and may help to spur a paradigm shift in the approach to its management, including in the setting of liver transplantation. Patients with MAFLD present significant challenges in the pre-, peri- and post-transplant settings, largely due to the presence of medical comorbidities that include obesity, metabolic syndrome and cardiovascular risk factors. As the community prevalence of MAFLD increases concurrently with the obesity epidemic, donor liver steatosis is also a current and future concern. This review outlines current epidemiology, nomenclature, management issues and outcomes of liver transplantation in patients with MAFLD.

Nonalcoholic Fatty Liver Disease-Evidence for a Thrombophilic State?

Nonalcoholic fatty liver disease is the leading cause of liver disease worldwide. It has expansive extrahepatic morbidity and mortality including increased rates of both cardiovascular disease and venous thromboembolism. Derangements in primary, secondary and tertiary hemostasis are found in nonalcoholic fatty liver disease independent of those ascribed to end-stage liver disease. The abnormalities across all stages of hemostasis explain the increased rates of clinically relevant thrombotic events, including pulmonary embolism, deep vein thrombosis and portal vein thrombosis, which on an epidemiologic basis appears to be independent of obesity and other traditional venous thromboembolic risk factors. However, given the complex interaction between obesity, body composition and nonalcoholic fatty liver disease and the potential for exercise to benefit all three, more research is needed to further define the role of each in contributing to the prohemostatic state of nonalcoholic fatty liver disease in order to improve patient oriented outcomes.

Outcomes of Liver Transplantation Among Older Recipients With Nonalcoholic Steatohepatitis in a Large Multicenter US Cohort: the Re-Evaluating Age Limits in Transplantation Consortium

The liver transplantation (LT) population is aging, with the need for transplant being driven by the growing prevalence of nonalcoholic steatohepatitis (NASH). Older LT recipients with NASH may be at an increased risk for adverse outcomes after LT. Our objective is to characterize outcomes in these recipients in a large multicenter cohort. All primary LT recipients ≥65 years from 2010 to 2016 at 13 centers in the Re-Evaluating Age Limits in Transplantation (REALT) consortium were included. Of 1023 LT recipients, 226 (22.1%) were over 70 years old, and 207 (20.2%) had NASH. Compared with other LT recipients, NASH recipients were older (68.0 versus 67.3 years), more likely to be female (47.3% versus 32.8%), White (78.3% versus 68.0%), Hispanic (12.1% versus 9.2%), and had higher Model for End-Stage Liver Disease-sodium (21 versus 18) at LT (P < 0.05 for all). Specific cardiac risk factors including diabetes with or without chronic complications (69.6%), hypertension (66.3%), hyperlipidemia (46.3%), coronary artery disease (36.7%), and moderate-to-severe renal disease (44.4%) were highly prevalent among NASH LT recipients. Graft survival among NASH patients was 90.3% at 1 year and 82.4% at 3 years compared with 88.9% at 1 year and 80.4% at 3 years for non-NASH patients (log-rank P = 0.58 and P = 0.59, respectively). Within 1 year after LT, the incidence of graft rejection (17.4%), biliary strictures (20.9%), and solid organ cancers (4.9%) were comparable. Rates of cardiovascular (CV) complications, renal failure, and infection were also similar in both groups. We observed similar posttransplant morbidity and mortality outcomes for NASH and non-NASH LT recipients. Certain CV risk factors were more prevalent in this population, although posttransplant outcomes within 1 year including CV events and renal failure were similar to non-NASH LT recipients.