Coronary flow reserve is impaired in patients with nonalcoholic fatty liver disease: association with liver fibrosis

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.

Impacts of Non-alcoholic Fatty Liver Disease on Acute Coronary Syndrome: Evidence and Controversies

PURPOSE OF REVIEW

Acute coronary syndrome (ACS) and non-alcoholic fatty liver disease (NAFLD) are two clinically common disease entities that share numerous risk factors. This review aimed to discuss the impacts of NAFLD on ACS.

RECENT FINDINGS

In an era of improved control of traditional risk factors, the substantial burden of cardiometabolic abnormalities has caused widespread concern. NAFLD is considered the hepatic component of metabolic syndrome, which can exert an impact on human health beyond the liver. Accumulating studies have demonstrated that NAFLD is closely related to cardiovascular disease, especially coronary artery disease. Interestingly, although recent data have suggested an association between NAFLD and the incidence and outcomes of ACS, the results are not consistent. In this review, we comprehensively summarized evidence and controversies regarding whether NAFLD is a contributor to either the development of ACS or worse outcomes in patients with ACS. The potential pathophysiological and molecular mechanisms involved in the impacts of NAFLD on ACS were also elucidated.

Cardiology Assessment of Patients Undergoing Evaluation for Orthotopic Liver Transplantation

Orthotopic liver transplantation (OLT) is a viable treatment option for end-stage liver disease. Significant perioperative stress is placed on the cardiovascular system because of hemodynamic changes and the length of the operation. Diagnosis and treatment of cardiovascular disease before OLT are imperative to ensure favorable outcomes. Considerable variability exists among practitioners caring for these patients. Institutions tailor their protocols on the basis of local and historical practices, the preferences of the cardiologists, and the OLT team, and algorithms are not often revised or updated on the basis of the available evidence. In collaboration with cardiology and hepatology experts from leading OLT centers, we sought to examine the diagnostic cardiovascular workup of OLT candidates, including a review of the available literature on the diagnostic modalities used to screen cardiovascular disease before OLT. We advocate an emphasis on noninvasive methods to assess cardiovascular risk with reserved use of invasive risk stratification in select patients.

Identification of Myocardial Insulin Resistance by Using Liver Tests: A Simple Approach for Clinical Practice

BACKGROUND

We report that myocardial insulin resistance (mIR) occurs in around 60% of patients with type 2 diabetes (T2D) and was associated with higher cardiovascular risk in comparison with patients with insulin-sensitive myocardium (mIS). These two phenotypes (mIR vs. mIS) can only be assessed using time-consuming and expensive methods. The aim of the present study is to search a simple and reliable surrogate to identify both phenotypes.

METHODS

Forty-seven patients with T2D underwent myocardial [18F]FDG PET/CT at baseline and after a hyperinsulinemic-euglycemic clamp (HEC) to determine mIR were prospectively recruited. Biochemical assessments were performed before and after the HEC. Baseline hepatic steatosis index and index of hepatic fibrosis (FIB-4) were calculated. Furthermore, liver stiffness measurement was performed using transient elastography.

RESULTS

The best model to predict the presence of mIR was the combination of transaminases, protein levels, FIB-4 score and HOMA (AUC = 0.95; sensibility: 0.81; specificity: 0.95). We observed significantly higher levels of fibrosis in patients with mIR than in those with mIS (p = 0.034). In addition, we found that patients with mIR presented a reduced glucose uptake by the liver in comparison with patients with mIS.

CONCLUSIONS

The combination of HOMA, protein, transaminases and FIB-4 is a simple and reliable tool for identifying mIR in patients with T2D. This information will be useful to improve the stratification of cardiovascular risk in T2D.

New Insights into Non-Alcoholic Fatty Liver Disease and Coronary Artery Disease: The Liver-Heart Axis

Non-alcoholic fatty liver disease (NAFLD) represents the hepatic expression of the metabolic syndrome and is the most prevalent liver disease. NAFLD is associated with liver-related and extrahepatic morbi-mortality. Among extrahepatic complications, cardiovascular disease (CVD) is the primary cause of mortality in patients with NAFLD. The most frequent clinical expression of CVD is the coronary artery disease (CAD). Epidemiological data support a link between CAD and NAFLD, underlain by pathogenic factors, such as the exacerbation of insulin resistance, genetic phenotype, oxidative stress, atherogenic dyslipidemia, pro-inflammatory mediators, and gut microbiota. A thorough assessment of cardiovascular risk and identification of all forms of CVD, especially CAD, are needed in all patients with NAFLD regardless of their metabolic status. Therefore, this narrative review aims to examine the available data on CAD seen in patients with NAFLD, to outline the main directions undertaken by the CVD risk assessment and the multiple putative underlying mechanisms implicated in the relationship between CAD and NAFLD, and to raise awareness about this underestimated association between two major, frequent and severe diseases.

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.

Cardiac risk stratification of the liver transplant candidate: A comprehensive review

Cardiovascular diseases (CVD) form a principal consideration in patients with end-stage liver disease (ESLD) undergoing evaluation for liver transplant (LT) with prognostic implications in the peri- and post-transplant periods. As the predominant etiology of ESLD continues to evolve, addressing CVD in these patients has become increasingly relevant. Likewise, as the number of LTs increase by the year, the proportion of older adults on the waiting list with competing comorbidities increase, and the demographics of LT candidates evolve with parallel increases in their CVD risk profiles. The primary goal of cardiac risk assessment is to preemptively reduce the risk of cardiovascular morbidity and mortality that may arise from hemodynamic stress in the peri- and post-transplant periods. The complex hemodynamics shared by ESLD patients in the pre-transplant period with adverse cardiovascular events occurring in only some of these recipients continue to challenge currently available guidelines and their uniform applicability. This review focusses on cardiac assessment of LT candidates in a stepwise manner with special emphasis on preoperative patient optimization. We hope that this will reinforce the importance of cardiovascular optimization prior to LT, prevent futile LT in those with advanced CVD beyond the stage of optimization, and thereby use the finite resources prudently.

Towards harnessing the value of organokine crosstalk to predict the risk for cardiovascular disease in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Importantly, NAFLD increases the risk for cardiovascular disease (CVD). A causal relationship has been substantiated. Given the pandemic proportions of NAFLD, a reliable scoring system for predicting the risk of NAFLD-associated CVD is an urgent medical need. We here review cumulative evidence suggesting that systemically released organokines - especially certain adipokines, hepatokines, and cardiokines - may serve this purpose. The underlying rationale is that these signalers directly communicate between white adipose tissue, liver, and heart as key players in the pathogenesis of NAFLD and resultant CVD events. Moreover, evidence suggests that these organ-specific cytokines are secreted in a biologically predetermined, cascade-like pattern. Consequently, upon pinpointing organokines of relevance, we sketch requirements to establish an algorithm predictive of the CVD risk in patients with NAFLD. Such an algorithm, as to be consolidated in the form of an applicable equation, may be improved continuously by machine learning. To the best of our knowledge, such an option has not yet been considered. Establishing and implementing a reliable algorithm for determining the NAFLD-associated CVD risk has the potential to save many NAFLD patients from life-threatening CVD events.

The Utility of Noninvasive PET/CT Myocardial Perfusion Imaging in Adult Liver Transplant Candidates

Background.

The optimal cardiovascular (CV) risk stratification in liver transplant (LT) candidates remains unclear. The aim of this study was to evaluate concordance of findings between dobutamine stress echocardiography (DSE), positron emission tomography/computed tomography myocardial perfusion imaging (PET/CT MPI), and left heart catheterization in adult LT candidates.

Methods.

Data on 234 consecutive adult LT candidates from February 2015 to June 2018 with PET/CT MPI were reviewed. Adverse CV outcomes were adjudicated via chart review by a board-certified cardiologist.

Results.

Median age was 60.8, body mass index 30.2 kg/m², and model of end-stage liver disease–sodium 14; 61% were male, and 54% had diabetes. Thirty-seven percent had nonalcoholic steatohepatitis and 29% alcohol-related liver disease. Sixty-five percent of patients had a DSE, of which 41% were nondiagnostic. No factors were independently associated with having a nondiagnostic DSE. The median global myocardial flow reserve correlated positively with hemoglobin and negatively with model of end-stage liver disease–sodium, age, ejection fraction, and body mass index. Moderate/high-risk MPIs were associated with older age and known CV disease. In patients with 2 cardiac testing modalities, findings were concordant in 87%. Eleven of 53 LT recipients experienced an adverse CV outcome, but no independent predictors were identified for this outcome.

Conclusions.

Results of different cardiac risk-stratification modalities were concordant across modalities the majority of the time in LT candidates, although these findings were not independently correlated with risk of post-LT CV outcomes. Given the high rates of nondiagnostic DSEs in this population, PET/CT MPI may be the preferred CV risk-stratification modality in older patients and those with known CV disease.

Diagnostic Yield of Coronary Angiography in Asymptomatic Orthotopic Liver Transplantation Candidates

BACKGROUND

The ideal cardiac risk stratification strategy for orthotopic liver transplantation (OLT) is unknown. Our institution performed coronary angiography for asymptomatic OLT candidates at high risk for CAD: ≥65 years of age, diabetic and ≥55 years of age or diagnosed ≥5 years, abnormal stress test, or at the discretion of the OLT committee.

METHODS

The analysis included 301 consecutive, asymptomatic OLT candidates who underwent coronary angiography. The primary outcome was the prevalence of obstructive CAD.

RESULTS

At 2-year follow-up, OLT was performed in 44.9%, and 42.2% died. The prevalence of obstructive CAD, involvement of the proximal or mid LAD, and 3-vessel CAD were 10.3%, 6.6%, and 0.7%, respectively. Percutaneous and surgical revascularization were performed in 7.0% and 1.3%, respectively. Stress test was performed in 54.8%. The sensitivity and specificity of stress testing were 0% and 87.1%, respectively. The negative and positive predictive values of stress testing were 91.4% and 0%, respectively. Chest computed tomography (CT) was performed in 83.1%. Moderate or severe coronary artery calcification (CAC) was present in 47.8%. The sensitivity and specificity of moderate or severe CAC were 88.9% and 57.3%, respectively. The negative and positive predictive values of moderate or severe CAC were 97.7% and 20.2%, respectively. Multivariate analysis demonstrated that CAC was an independent predictor of obstructive CAD (HR 10.7; 95% CI 3.2-37.9; p < 0.001).

CONCLUSIONS

The prevalence of obstructive CAD in asymptomatic OLT candidates at high risk was uncommon. Alternative diagnostic strategies may be preferred to coronary angiography.

Hepatic small extracellular vesicles promote microvascular endothelial hyperpermeability during NAFLD via novel-miRNA-7

BACKGROUND

A recent study has reported that patients with nonalcoholic fatty liver disease (NAFLD) are more susceptible to coronary microvascular dysfunction (CMD), which may predict major adverse cardiac events. However, little is known regarding the causes of CMD during NAFLD. In this study, we aimed to explore the role of hepatic small extracellular vesicles (sEVs) in regulating the endothelial dysfunction of coronary microvessels during NAFLD.

RESULTS

We established two murine NAFLD models by feeding mice a methionine-choline-deficient (MCD) diet for 4 weeks or a high-fat diet (HFD) for 16 weeks. We found that the NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome-dependent endothelial hyperpermeability occurred in coronary microvessels during both MCD diet and HFD-induced NAFLD. The in vivo and in vitro experiments proved that novel-microRNA(miR)-7-abundant hepatic sEVs were responsible for NLRP3 inflammasome-dependent endothelial barrier dysfunction. Mechanistically, novel-miR-7 directly targeted lysosomal associated membrane protein 1 (LAMP1) and promotes lysosomal membrane permeability (LMP), which in turn induced Cathepsin B-dependent NLRP3 inflammasome activation and microvascular endothelial hyperpermeability. Conversely, a specific novel-miR-7 inhibitor markedly improved endothelial barrier integrity. Finally, we proved that steatotic hepatocyte was a significant source of novel-miR-7-contained hepatic sEVs, and steatotic hepatocyte-derived sEVs were able to promote NLRP3 inflammasome-dependent microvascular endothelial hyperpermeability through novel-miR-7.

CONCLUSIONS

Hepatic sEVs contribute to endothelial hyperpermeability in coronary microvessels by delivering novel-miR-7 and targeting the LAMP1/Cathepsin B/NLRP3 inflammasome axis during NAFLD. Our study brings new insights into the liver-to-microvessel cross-talk and may provide a new diagnostic biomarker and treatment target for microvascular complications of NAFLD.

Interplay between non-alcoholic fatty liver disease and cardiovascular risk in an asymptomatic general population

BACKGROUND AND AIMS

Non-alcoholic fatty liver (NAFLD) is a major cause of liver disease worldwide leading also to a higher risk of cardiovascular events. We aimed to evaluate the impact of fatty liver and fibrosis on cardiovascular risk in a general population.

METHODS

Five hundred and forty-two subjects included in the community-based ABCD (Alimentazione, Benessere Cardiovascolare e Diabete) study were recruited. Steatosis (controlled attenuation parameter > 288 dB/m) and severe fibrosis (low risk, liver stiffness measurement [LSM] < 7.9 KPa with M probe and < 5.7 KPa with XL probe; intermediate risk, LSM 7.9-9.5 KPa with M probe and 5.7-9.2 KPa with XL probe; high risk, LSM ≥ 9.6 KPa with M probe and ≥ 9.3 KPa with XL probe) were assessed with FibroScan. Cardiovascular risk was evaluated by the atherosclerotic cardiovascular disease (ASCVD) risk estimator and defined low if < 5%, borderline if 5-7.4%, intermediate if 7.5-19.9% and high if ≥ 20%. Intima-media thickness (IMT) was measured with ultrasound.

RESULTS

Prevalence of steatosis and of severe fibrosis in this cohort was 31.7% and 4.8%, respectively. ASCVD score was evaluated in patients with and without steatosis and according to the risk of severe fibrosis. By ordinal regression analysis, both steatosis (odds ratio [OR] 1.62, 95% confidence interval [CI] 1.13-2.33, P = 0.009) and severity of fibrosis (OR 1.67, 95% CI 1.18-2.36, P = 0.003) were independent risk factors for a higher ASCVD risk after adjusting for obesity. Subjects with NAFLD, when compared with those without, did not differ for IMT (0.75 vs 0.72 mm; P = 0.11) and IMT ≥ 1 mm (15.6% vs 12.1%; P = 0.24). Higher prevalence of IMT ≥ 1 mm was found in patients at high or intermediate risk of severe fibrosis (24% and 28.6%, respectively) compared with those at low risk (12.1%) (P = 0.03); this association was maintained after adjusting for confounders (OR 2.70, 95% CI 1.01-2.86, P = 0.04).

CONCLUSION

In the setting of a general adult population, the presence of NAFLD and severe fibrosis are associated with to a higher cardiovascular risk profile, pointing towards the need for specific preventive measures.

Nonalcoholic Fatty Liver Disease and Cardiovascular Disease: Overlapping Mechanisms

Nonalcoholic fatty liver disease (NAFLD) denotes a condition with excess fat in the liver. The prevalence of NAFLD is increasing, averaging > 25% of the Western population. In 25% of the patients, NAFLD progresses to its more severe form: nonalcoholic steatohepatitis and >25% of these progress to cirrhosis following activation of inflammatory and fibrotic processes. NAFLD is associated with obesity, type 2 diabetes, and the metabolic syndrome and represents a considerable and increasing health burden. In the near future, NAFLD cirrhosis is expected to be the most common cause for liver transplantation. NAFLD patients have an increased risk of developing cardiovascular disease as well as liver-related morbidity. In addition, hepatic steatosis itself appears to represent an independent cardiovascular risk factor. In the present review, we provide an overview of the overlapping mechanisms and prevalence of NAFLD and cardiovascular disease.

Testosterone Deficiency, Long-Term Testosterone Therapy, and Inflammation

OBJECTIVES

We aimed to evaluate the association of testosterone deficiency with inflammation and how long-term testosterone therapy affects inflammation biomarkers over time.

METHODS

We conducted a 2-component study. First, we conducted a cross-sectional study using the recently released 2015-2016 National Health and Nutrition Examination Survey (NHANES) data to examine the association between testosterone deficiency and inflammation biomarkers including high sensitivity C-reactive protein (hsCRP), liver enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the US general population. Then we conducted a longitudinal study to investigate the longitudinal effect of testosterone therapy on inflammation biomarkers and the risk of cardiovascular events, using data from 776 hypogonadal men based on a registry study in Germany with up to 11 years' follow-up.

RESULTS

The adjusted odds ratios (ORs) describing the associations between testosterone deficiency and hsCRP ≥ 3mg/L, ALT > 40U/L, and AST > 40U/L were 1.81 (P-value < 0.001), 1.46 (P-value = 0.009), and 0.99 (P-value = 0.971), respectively. In the control group, CRP, ALT, and AST levels increased by 0.003 (95%CI: -0.001, 0.007) mg/L, 0.157 U/L (95%CI: 0.145, 0.170), and 0.147 (95%CI: 0.136, 0.159) U/L per month, while in the treatment group, CRP, ALT, and AST levels decreased by 0.05 (95%CI: -0.055, -0.046) mg/L, 0.142 U/L (95%CI: -0.154, -0.130), and 0.148 (95%CI: -0.158, -0.137) U/L per month.

CONCLUSION

Testosterone deficiency was associated with an increased level of inflammation; long-term testosterone therapy alleviated inflammation among hypogonadal men, which may contribute to the reduced cardiovascular risk. Future large trials are warranted to confirm our observational study findings.

Prognostic significance of liver stiffness assessed by fibrosis-4 index in patients with heart failure

BACKGROUND

Heart failure (HF)-related congestive hepatopathy is a well-recognized problem in management of HF. The fibrosis-4 (FIB4) index calculated by [age × aspartate aminotransferase (IU/L)/platelet count (10⁹ /L) × square root of alanine aminotransferase (IU/L)] is useful for evaluating liver stiffness. We aimed to investigate the impact of the FIB4 index on prognosis in patients with HF.

METHODS AND RESULTS

Consecutive HF patients referred for hospitalization at Kumamoto University Hospital, Japan, were registered between 2006 and 2015. We observed cardiovascular outcomes in each type of HF [HF with reduced left ventricular ejection fraction (LVEF) (HFrEF), HF with mid-range LVEF (HFmrEF) and with preserved LVEF (HFpEF)] according to their FIB4 index; Group 1 (FIB4 index <1.3), Group 2 (FIB4 index: 1.3-2.67), and Group 3 (FIB4 index >2.67). This study enrolled 83 HFrEF patients, 117 HFmrEF patients, and 504 HFpEF patients. In HFpEF patients, the Kaplan-Meier curve revealed that Group 3 had a significantly higher rate of total cardiovascular events compared with the other two groups. By contrast, the occurrences of total cardiovascular events were not different among three groups in HFrEF and HFmrEF patients. Multivariate Cox proportional hazard analysis with significant factors in univariate analysis identified that the FIB4 index as an independent and significant predictor for future total cardiovascular events in HFpEF patients (hazard ratio: 1.09, 95% confidence interval: 1.03-1.15, P = 0.001).

CONCLUSIONS

The FIB4 index was a significant predictor for total cardiovascular events in HFpEF.

Non-alcoholic fatty liver disease: a metabolic burden promoting atherosclerosis

Non-alcoholic fatty liver disease (NAFLD) has become the fastest growing chronic liver disease, with a prevalence of up to 25% worldwide. Individuals with NAFLD have a high risk of disease progression to cirrhosis, hepatocellular carcinoma (HCC), and liver failure. With the exception of intrahepatic burden, cardiovascular disease (CVD) and especially atherosclerosis (AS) are common complications of NAFLD. Furthermore, CVD is a major cause of death in NAFLD patients. Additionally, AS is a metabolic disorder highly associated with NAFLD, and individual NAFLD pathologies can greatly increase the risk of AS. It is increasingly clear that AS-associated endothelial cell damage, inflammatory cell activation, and smooth muscle cell proliferation are extensively impacted by NAFLD-induced systematic dyslipidemia, inflammation, oxidative stress, the production of hepatokines, and coagulations. In clinical trials, drug candidates for NAFLD management have displayed promising effects for the treatment of AS. In this review, we summarize the key molecular events and cellular factors contributing to the metabolic burden induced by NAFLD on AS, and discuss therapeutic strategies for the improvement of AS in individuals with NAFLD.

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.

Recent testosterone drop-off and risk of cardiovascular events

Low baseline testosterone level has been associated with the development of risk factors for cardiovascular disease such as insulin resistance and obesity. In addition to the absolute testosterone level, remarkable changes in testosterone level may have an acute effect on cardiovascular disease development and progression, which has been rarely investigated. In this study, we used a clinical dataset of 376 hypogonadal men whose testosterone levels were measured every six months for up to 11 years from a registry study in Germany, and conducted survival analyses to investigate the effect of testosterone changes since the last visit (time-varying) on the risk of cardiovascular events. Given the potential discrepancies in comorbidity conditions among patients with prior cardiovascular events and those without, all the analyses were stratified by patients' prior cardiovascular event status. We found the effects were not different among patients with prior cardiovascular events and those without. Regardless of patients' prior cardiovascular event status, patients with larger testosterone declines (≥3.12 nmol/L, 90^th percentile) since the last visit were more likely to experience myocardial infarction. In conclusion, recent pronounced testosterone drop-offs may affect the risk of cardiovascular events among hypogonadal men. Future longitudinal studies are needed to confirm our exploratory study findings.

Association between non-alcoholic fatty liver disease and myocardial glucose uptake measured by 18F-fluorodeoxyglucose positron emission tomography

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has emerged as an independent risk factor for cardiovascular diseases. However, there were few studies evaluating the condition of myocardial glucose metabolism in patients with NAFLD. Therefore, the aim of this study was to investigate the association between NAFLD and myocardial glucose uptake assessed by using 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and whether or not alteration of myocardial glucose uptake could be an indicator linking to cardiac dysfunction in NAFLD individuals.

METHODS AND RESULTS

A total of 743 asymptomatic subjects (201 with NAFLD, 542 without NAFLD) were retrospectively studied. The ratio of maximum myocardium FDG uptake to the mean standardized uptake value of liver (SUVratio) was calculated to estimate myocardial glucose uptake by using 18F-FDG PET. The diagnosis of fatty liver and fatty liver grading was confirmed by unenhanced CT according to diagnostic criterion of previous studies. The myocardial geometric and functional data were obtained by echocardiogram. Myocardial glucose uptake was significantly lower in individuals with NAFLD compared with those without fatty liver (P < .001). When analysis of association trend was performed, SUVratio quartiles showed correlated inversely and strongly with liver steatosis (P < .001). NAFLD patients with lower myocardial glucose uptake were more likely to have higher proportion of increased LV filling pressure (P < .05). A significant relationship between myocardial SUVratio and E/e' ratio was presented in the trend analysis (P < .05). Moreover, multivariate regression analysis showed that myocardial glucose uptake was independently associated with NAFLD after adjusting for clinical important factors (all P < .001).

CONCLUSIONS

The presence of NAFLD in otherwise healthy subjects is closely associated with decreased myocardial glucose uptake assessing by 18F-FDG PET imaging. Furthermore, the NAFLD individuals with lower myocardial glucose uptake are more likely to have high risk of having impaired diastolic heart function.

A preliminary report about the detection of ventricular repolarisation in patients with non-alcoholic fatty liver disease

Objectives

Non-alcoholic fatty liver disease (NAFLD) is a multisystem disease which can affect the cardiovascular system as well. We conducted this study to determine the cardiac effects of NAFLD such as conduction of impulse and ventricular repolarisation on electrocardiography (ECG).

Methods

In this study, we recruited patients with risk factors for NAFLD (group I; n = 23) and NAFLD patients (group II; n = 74) from Shar Hospital in Sulaimani City, Iraq. We analysed anthropometric measurements, serum fasting lipid profile, glucose levels, liver enzymes, and ECG recordings.

Results

ECG recordings showed significantly longer PR intervals, significantly shorter QTcB and JTc intervals, and a higher Tp-e/QTcB ratio in group II patients than in group I patients. These abnormalities were not associated with risk factors for diabetes. The TQ duration was significantly correlated with serum alanine aminotransferase (r = 0.411, p < 0.001) and aspartate aminotransferase (r = 0.272, p = 0.019) levels.

Conclusion

In our study, the presence of significant abnormalities in ventricular repolarisation suggests that patients with newly diagnosed NAFLD have subclinical cardiac stress and a higher risk of ventricular arrhythmias.

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Non-alcoholic fatty liver disease patients are at risk of developing ventricular repolarization.

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Abnormal electrocardiograph changes are related to the serum levels of liver enzymes.

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People at risk of developing non-alcoholic liver disease are also have abnormal ventricular repolarization indices.

Dysregulated Neurovascular Control Underlies Declining Microvascular Functionality in People With Non-alcoholic Fatty Liver Disease (NAFLD) at Risk of Liver Fibrosis

Background/Aims

Increasing evidence shows that non-alcoholic fatty liver disease (NAFLD) is associated with dysregulation of microvascular perfusion independently of established cardio-metabolic risk factors. We investigated whether hepatic manifestations of NAFLD such as liver fibrosis and liver fat are associated with microvascular hemodynamics through dysregulation of neurovascular control.

Methods

Microvascular dilator (post-occlusive reactive hyperemia) and sympathetically mediated constrictor (deep inspiratory breath-hold) responses were measured at the forearm and finger, respectively, using laser Doppler fluximetry. Non-linear complexity-based analysis was used to assess the information content and variability of the resting blood flux (BF) signals, attributable to oscillatory flow-motion activity, and over multiple sampling frequencies.

Results

Measurements were made in 189 adults (113 men) with NAFLD, with (n = 65) and without (n = 124) type 2 diabetes mellitus (T2DM), age = 50.9 ± 11.7 years (mean ± SD). Microvascular dilator and constrictor capacity were both negatively associated with age (r = −0.178, p = 0.014, and r = −0.201, p = 0.007, respectively) and enhanced liver fibrosis (ELF) score (r = −0.155, p = 0.038 and r = −0.418, p < 0.0001, respectively). There was no association with measures of liver fat, obesity or T2DM. Lempel-Ziv complexity (LZC) and sample entropy (SE) of the BF signal measured at the two skin sites were associated negatively with age (p < 0.01 and p < 0.001) and positively with ELF score (p < 0.05 and p < 0.0001). In individuals with an ELF score ≥7.8 the influence of both neurogenic and respiratory flow-motion activity on LZC was up-rated (p < 0.0001).

Conclusion

Altered microvascular network functionality occurs in adults with NAFLD suggesting a mechanistic role for dysregulated neurovascular control in individuals at risk of severe liver fibrosis.

Relationship between non-alcoholic fatty liver disease and cardiovascular disease

With the in-depth study of non-alcoholic fatty liver disease (NAFLD), it has been found in recent years that NAFLD is closely related to cardiovascular disease (CVD). It has been proved that NAFLD is not only an important risk factor for CVD, but it is also an important mechanism of atherosclerosis, coronary heart disease, and hypertension in young people. This article reviews the recent progress in the understanding of the relationship between NAFLD and CVD, with an aim to improve the knowledge of CVD physicians on liver disease and provide reference for prevention and treatment of these conditions.

Non-alcoholic fatty liver disease: A growing public health problem in Turkey

Non-alcoholic fatty liver disease (NAFLD) is histologically classified as either non-alcoholic fatty liver or non-alcoholic steatohepatitis (NASH). NASH is the progressive subtype of NAFLD. Individuals with NASH are at significant risk of developing hepatic fibrosis, cirrhosis, hepatocellular carcinoma, and liver-related and all-cause mortality. NAFLD is closely associated with obesity, type 2 diabetes mellitus (T2DM), metabolic syndrome, and cardiovascular events. Its prevalence is estimated to be above 30% in Turkey; and recent studies confirm this estimate. According to these studies, the prevalence of NAFLD in Turkey is between 48.3% and 60.1%. Currently, Turkey can be considered a risky region in terms of NAFLD burden as it is the most obese country in Europe with an obesity prevalence of 32.1% according to the 2016 World Health Organization data. Moreover, along with the increasing prevalence of obesity and T2DM in Turkey, the burden of NAFLD is estimated to increase in the upcoming decade. Despite the growing burden, we lack well-designed systemic studies that investigate NAFLD and its marked histological severity. In this review, we present studies on the burden of NAFLD and NASH, the natural history of NAFLD, and its association with other systemic diseases conducted with Turkish populations.

Liver transplantation and cardiac illness: Current evidences and future directions

Contraindications to liver transplantation are gradually narrowing. Cardiac illness and chronic liver disease may manifest independently or may be superimposed on each other due to shared pathophysiology. Cardiac surgery involving the cardiopulmonary bypass in patients with Child-Pugh Class C liver disease is associated with a high risk of perioperative morbidity and mortality. Liver transplantation involves hemodynamic perturbations, volume shifts, coagulation abnormalities, electrolyte disturbances, and hypothermia, which may prove fatal in patients with cardiac illness depending upon the severity. Additionally, cardiovascular complications are the major cause of adverse postoperative outcomes after liver transplantation even in the absence of cardiac pathologies. Clinical decision-making has remained an unsettled issue in these clinical scenarios. The absence of randomized clinical studies has further crippled our endeavours for a consensus on the management of patients with end-stage liver disease with cardiac illness. This review seeks to address this complex clinical setting by gathering information from published literature. The management algorithm in this review may facilitate clinical decision making and augur future research.

Cardiovascular Risk in Fatty Liver Disease: The Liver-Heart Axis-Literature Review

According to the World Health Organization, cardiovascular disease (CVD) remains the leading cause of death worldwide, accounting for approximately 18 million deaths per year. Nevertheless, the worldwide prevalence of metabolic diseases, such as type 2 diabetes mellitus, obesity, and non-alcoholic fatty liver disease (NAFLD), also known to be common risk factors for CVD, have dramatically increased over the last decades. Chronic alcohol consumption is a major cause of chronic liver diseases (CLD) as well as being a major health care cost expenditure accounting for the spending of tremendous amounts of money annually. NAFLD has become one of the major diseases plaguing the world while standing as the most common cause of liver disease in the Western countries by representing about 75% of all CLD. Currently, the most common cause of death in NAFLD remains to be CVD. Several mechanisms have been suggested to be responsible for associating FLD with CVD through several mechanisms including low-grade systemic inflammation, oxidative stress, adipokines, endoplasmic reticulum stress, lipotoxicity and microbiota dysbiosis which may also be influenced by other factors such as genetic and epigenetic variations. Despite of all this evidence, the exact mechanisms of how FLD can causally contribute to CVD are not fully elucidated and much remains unknown. Moreover, the current literature supports the increasing evidence associating FLD with several cardiovascular (CV) adverse events including coronary artery disease, increased subclinical atherosclerosis risk, structural alterations mainly left ventricular hypertrophy, increased epicardial fat thickness, valvular calcifications including aortic valve sclerosis and mitral annular calcification and functional cardiac modifications mainly diastolic dysfunction in addition to cardiac arrhythmias such as atrial fibrillation and ventricular arrythmias and conduction defects including atrioventricular blocks and bundle branch blocks. Patients with FLD should be evaluated and managed accordingly in order to prevent further complications. Possible management methods include non-pharmacological strategies including life style modifications, pharmacological therapies as well as surgical management. This review aims to summarize the current state of knowledge regarding the pathophysiological mechanisms linking FLD with an increased CV risk, in addition to associated CV adverse events and current management modalities.

Risk stratification of myocardial injury after liver transplantation in patients with computed tomographic coronary angiography-diagnosed coronary artery disease

We aimed to determine if the severity of computed tomographic coronary angiography (CTCA)-diagnosed coronary artery disease (CAD) is associated with postliver transplantation (LT) myocardial infarction (MI) within 30 days and early mortality. We retrospectively evaluated 2118 consecutive patients who underwent CAD screening using CTCA. Post-LT type-2 MI, elicited by oxygen supply-and-demand mismatch within a month after LT, was assessed according to the severity of CTCA-diagnosed CAD. Obstructive CAD (>50% narrowing, 9.2% prevalence) was identified in 21.7% of patients with 3 or more known CAD risk factors of the American Heart Association. Post-LT MI occurred in 60 (2.8%) of total patients in whom 90-day mortality rate was 16.7%. Rates of post-LT MI were 2.1%, 3.1%, 3.4%, 4.3%, and 21.4% for normal, nonobstructive CAD, and 1-, 2-, and 3-vessel obstructive CAD, respectively. Two-vessel or 3-vessel obstructive CAD showed a 4.9-fold higher post-LT MI risk compared to normal coronary vessels. The sensitivity and negative predictive value of obstructive CAD in detecting post-LT MI were, respectively, 20% and 97.5%. In conclusion, negative CTCA finding in suspected patients can successfully exclude post-LT MI, whereas proceeding with invasive angiography is needed to further risk-stratify in patients with significant CTCA-diagnosed CAD. Prognostic role of CTCA in predicting post-LT MI needs further research.

Association between Nonalcoholic Fatty Liver Disease at CT and Coronary Microvascular Dysfunction at Myocardial Perfusion PET/CT

Background Cardiovascular disease is a major cause of mortality in patients with nonalcoholic fatty liver disease (NAFLD). However, the association of NAFLD with coronary microvascular dysfunction is, to our knowledge, unknown. Purpose To determine whether coronary microvascular dysfunction is more prevalent in patients with NAFLD and to determine whether coronary microvascular dysfunction predicts major adverse cardiac events (MACE) independently of NAFLD. Materials and Methods This retrospective study (2006-2014) included patients without evidence of obstructive epicardial coronary artery disease and healthy left ventricular ejection fraction (≥40%) at a clinical rest and stress myocardial perfusion PET/CT. NAFLD was defined by a mean hepatic attenuation of less than 40 HU at CT and coronary microvascular dysfunction as a coronary flow reserve (CFR) of less than 2.0. A composite of all-cause mortality, myocardial infarction, coronary revascularization, and hospitalization because of heart failure comprised MACE (130 of 886 patients; 14.7%). The relation between NAFLD and MACE was assessed by using multivariable Cox regression analysis. Results Among 886 patients (mean age, 62 years ± 12 [standard deviation]; 631 women [mean age, 62 years ± 12 years] and 255 men [mean age, 61 years ± 12]; and ejection fraction, 63% ± 9), 125 patients (14.1%) had NAFLD and 411 patients (46.4%) had coronary microvascular dysfunction. Coronary microvascular dysfunction was more prevalent (64.8% vs 43.4%; P < .001) and CFR was lower (1.9 ± 1.1 vs 2.2 ± 0.7; P < .001) in patients with NAFLD compared with those without NAFLD. NAFLD independently predicted coronary microvascular dysfunction (P = .01). The interaction of NAFLD and male sex predicted MACE (hazard ratio, 1.45; 95% confidence interval: 1.08, 1.69; P = .008) and coronary microvascular dysfunction remained associated with MACE (adjusted hazard ratio, 1.46; 95% confidence interval: 1.02, 2.07; P = .04). Conclusion Coronary microvascular dysfunction was more prevalent in patients with nonalcoholic fatty liver disease and predicted major adverse cardiac events independently of nonalcoholic fatty liver disease. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Ambale-Venkatesh and Lima in this issue.

Coronary flow reserve in patients with primary biliary cholangitis

BACKGROUND

It is still not clear whether primary biliary cholangitis (PBC) is associated with abnormalities of the cardiovascular system. We aimed to assess the relationship between PBC and coronary flow reserve (CFR).

METHODS

Our inclusion criterion was a diagnosis of PBC with no clinical evidence of heart disease or metabolic syndrome. Coronary flow velocity in the left anterior descending coronary artery was measured using transthoracic Doppler echocardiography at rest (DFVr), and during adenosine infusion (DFVh). The corrected CFR (cCFR) was defined as the ratio of DFVh to DFVr corrected for cardiac workload (cDFVr). Microvascular resistance was also assessed in baseline (BMR) and hyperemic conditions (HMR).

RESULTS

37 PBC patients and 37 sex- and age-matched controls were considered. The cCFR was significantly lower in PBC patients (2.8 ± 0.7 vs. 3.7 ± 0.7, p < 0.0001), and abnormal (≤2.5) in 13 (35%) of them, but in none of the controls (p < 0.0001). The cDFVr was higher in patients with abnormal cCFR (29.0 ± 6.0 vs. 20.4 ± 4.5 cm/sec, p < 0.0001). The CFR and cCFR did not correlate with any characteristics of PBC, comorbidities or Framingham risk scores. The BMR and HMR correlated with time since PBC diagnosis and duration of symptoms.

CONCLUSION

The CFR is reduced in PBC, apparently due to mechanisms correlating with the time since diagnosis. In particular, the higher cDFVr with a lower basal resistance in patients with cCFR ≤ 2.5 suggests a compensatory mechanism against any cardiomyocyte bioenergetics impairment.

NAFLD and cardiovascular disease

Nonalcoholic fatty liver disease (NAFLD) is an important cause of chronic hepatic disease and liver transplant in Western societies. The increasing prevalence is related to dietary changes and sedentarism and follows the increasing frequency of obesity and type 2 diabetes mellitus.

Growing evidence of association of NAFLD with cardiovascular diseases (CVD), independent of cardiovascular risk factors, has prompted the clarification of whether the liver is mainly a key-effector or a target-organ of the metabolic disarrangements in the metabolic syndrome. The therapeutic strategies able to alter liver disease progression and, through this, reduce the cardiovascular risk have also been tested in the last 2 decades.

This review focus on the possible interactions between hepatic disease, metabolic syndrome, and CVD, and on their implications for clinical practice.

Multidisciplinary approach to cardiac and pulmonary vascular disease risk assessment in liver transplantation: An evaluation of the evidence and consensus recommendations

Liver transplant (LT) candidates today are older, have greater medical severity of illness, and have more cardiovascular comorbidities than ever before. In addition, there are specific cardiovascular responses in cirrhosis that can be detrimental to the LT candidate. Cirrhotic cardiomyopathy, a condition characterized by increased cardiac output and a reduced ventricular response to stress, is present in up to 30% of patients with cirrhosis, thus challenging perioperative management. Current noninvasive tests that assess for subclinical coronary and myocardial disease have low sensitivity, and altered hemodynamics during the LT surgery can unmask latent cardiovascular disease either intraoperatively or in the immediate postoperative period. Therefore, this review, assembled by a group of multidisciplinary experts in the field and endorsed by the American Society of Transplantation Liver and Intestine and Thoracic and Critical Care Communities of Practice, provides a critical assessment of the diagnosis of cardiac and pulmonary vascular disease and interventions aimed at managing these conditions in LT candidates. Key points and practice-based recommendations for the diagnosis and management of cardiac and pulmonary vascular disease in this population are provided to offer guidance for clinicians and identify gaps in knowledge for future investigations.

Severity of nonalcoholic fatty liver disease on sonography and risk of coronary heart disease

PURPOSE

To evaluate the relationship between nonalcoholic fatty liver disease (NAFLD) on sonography (US) and the risk of coronary heart disease (CHD) as well as the predictive value of US-diagnosed NAFLD to determine intermediate/high CHD risk compared with as well as in combination on with NAFLD fibrosis score (NFS).

METHODS

This retrospective study included 1,276 patients examined between November 2015 and August 2016. NAFLD was categorized as absent, mild, moderate, or severe based on liver-to-kidney echogenicity, visibility of intrahepatic vessel walls, and the diaphragm. The Framingham risk score (FRS) and NFS were used to predict CHD risk and hepatic fibrosis severity. Spearman correlation test, multivariate-adjusted logistic regression analysis, and receiver operating characteristic curves were used for statistical evaluation.

RESULTS

FRS increased as NAFLD severity increased, and US-determined NAFLD severity and FRS were highly positively correlated (r = 0.683, p < 0.001). The odds ratios for intermediate/high CHD risk increased with increasing NAFLD severity. The predictive performance of US-determined NAFLD severity for determining intermediate/high CHD risk in NAFLD patients was 0.738. There was no significant difference between US-determined NAFLD severity and NFS in terms of identifying intermediate/high CHD risk (p = 0.88). However, the combination of US-determined NAFLD severity and NFS significantly improved the ability to distinguish intermediate/high CHD risk compared with that of US-determined NAFLD severity or NFS alone (p < 0.001 for both).

CONCLUSIONS

US-determined NAFLD severity was well correlated with FRS and associated with the prevalence of intermediate/high CHD risk. The combination of US-determined NAFLD severity and NFS may be useful for predicting CHD risk. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:391-399, 2017.

Liver stiffness assessed by Fibrosis-4 index predicts mortality in patients with heart failure

Objective

Liver dysfunction due to heart failure (HF) is known as congestive hepatopathy. It has recently been reported that liver stiffness assessed by transient elastography reflects increased central venous pressure. The Fibrosis-4 (FIB4) index (age (years) × aspartate aminotransferase (IU/L)/platelet count (10⁹/L) × square root of alanine aminotransferase (IU/L)) is expected to be useful for evaluating liver stiffness in patients with non-alcoholic fatty liver disease. We aimed to investigate the impact of the FIB4 index on HF prognosis, with consideration for liver fibrosis markers and underlying cardiac function.

Methods

Consecutive 1058 patients with HF who were admitted to our hospital were divided into three groups based on their FIB4 index: first (FIB4 index <1.72, n=353), second (1.72≤FIB4 index <3.01, n=353) and third tertiles (3.01≤FIB4 index, n=352). We prospectively followed for all-cause mortality.

Results

During the follow-up period (mean 1047 days), 246 deaths occurred. In the Kaplan-Meier analysis, all-cause mortality progressively increased from the first to third groups (12.2%, 21.0% and 36.6%, p<0.01). In the Cox proportional hazard analysis, FIB4 index was an independent predictor of all-cause mortality in patients with HF (p<0.05). In comparisons of laboratory and echocardiographic findings, the third tertile had higher levels of type IV collagen 7S, procollagen type III peptide, hyaluronic acid, left atrial volume, mitral valve E/e’, inferior vena cava diameter and right atrial end systolic area (p<0.01, respectively).

Conclusion

The FIB4 index, a marker of liver stiffness, is associated with higher all-cause mortality in patients with HF.

One-year GH replacement therapy reduces early cardiac target organ damage (TOD) in adult GHD patients

Hypopituitarism reduces life expectancy and increases the risk of cardiovascular and cerebrovascular diseases, as well as death. Abnormalities in the cardiovascular system may be independently related to GH deficiency (GHD). The aim of this study was to prospectively investigate coronary flow reserve and diastolic function in GHD adult patients at diagnosis and after 1 year of GH replacement therapy. As control group, an age- and sex-matched population was chosen. All patients and controls were non-smokers, non-diabetic, and normotensive, with no history of vascular disease. 14 patients with adult-onset GHD and 17 controls represent the two study groups. Anthropometric data, blood pressure, lipid profile, glycosylated hemoglobin (HbA1c) and IGF-I plasma levels, coronary flow reserve (CFR), and LV diastolic function (evaluated by E/A) were collected in all subjects before and after 12 months of GH replacement therapy. Compared with controls, systolic and diastolic blood pressure and LDL cholesterol levels were significantly higher at baseline and return, comparable to controls after 1 year of GH replacement (GHRT). GHD patients showed a blunted CFR at baseline (P < 0.001) and a significant improvement after GHRT, returning to values comparable with those recorded in the control group. In addition, after therapy a significant (P < 0.001) improvement in E/A was recorded. One year of GH therapy improves CFR and E/A in the patient population analyzed, thereby encouraging the early start of GHRT.

Cardiovascular Risk Reduction in Patients with Nonalcoholic Fatty Liver Disease: The Potential Role of Ezetimibe

Nonalcoholic fatty liver disease (NAFLD) is widely considered to be the hepatic manifestation of the metabolic syndrome and is closely linked to dyslipidemia, obesity, and insulin resistance. Patients with NAFLD have increased mortality when compared to the general population, primarily related to cardiovascular disease or malignancy. The biologic mechanisms that link NAFLD to cardiovascular disease include expansion of visceral adipose tissue, atherogenic dyslipidemia, impaired insulin signaling, systemic inflammation, and endothelial dysfunction. Currently, there are no approved therapies for NAFLD. It has recently been hypothesized that reducing the delivery of dietary cholesterol using the hypolipidemic agent, ezetimibe, could benefit patients with NAFLD. By potently inhibiting the Niemann-Pick C1-Like 1 (NPC1L1) sterol receptor on intestinal enterocytes and within the liver, ezetimibe blocks exogenous cholesterol absorption and has been shown to improve biochemical markers of NAFLD, improve insulin sensitivity and decrease hepatic steatosis. This review summarizes the clinical and epidemiological evidence for the relationship between NAFLD and cardiovascular risk and examines the potential therapeutic role of ezetimibe.

Nonalcoholic fatty liver disease, association with cardiovascular disease and treatment. (I). Nonalcoholic fatty liver disease and its association with cardiovascular disease

Non-alcoholic fatty liver disease (NAFLD) comprises a series of histologically lesions similar to those induced by alcohol consumption in people with very little or no liver damage. The importance of NAFLD is its high prevalence in the Western world and, from the point of view of the liver, in its gradual progression from steatosis to steatohepatitis, cirrhosis, and liver cancer. During the last decade it has been observed that NAFLD leads to an increased cardiovascular risk with acceleration of arteriosclerosis and events related to it, being the main cause of its morbidity and mortality. This review, updated to January 2016, consists of two parts, with the first part analysing the association of NAFLD with cardiovascular disease.

Ectopic and Visceral Fat Deposition in Lean and Obese Patients With Type 2 Diabetes

BACKGROUND

Type 2 diabetes (T2D) and obesity are associated with nonalcoholic fatty liver disease, cardiomyopathy, and cardiovascular mortality. Both show stronger links between ectopic and visceral fat deposition, and an increased cardiometabolic risk compared with subcutaneous fat.

OBJECTIVES

This study investigated whether lean patients (Ln) with T2D exhibit increased ectopic and visceral fat deposition and whether these are linked to cardiac and hepatic changes.

METHODS

Twenty-seven obese patients (Ob) with T2D, 15 Ln-T2D, and 12 normal-weight control subjects were studied. Subjects underwent cardiac computed tomography, cardiac magnetic resonance imaging (MRI), proton and phosphorus MR spectroscopy, and multiparametric liver MR, including hepatic proton MRS, T1- and T2*-mapping yielding "iron-corrected T1" [cT1].

RESULTS

Diabetes, with or without obesity, was associated with increased myocardial triglyceride content (p = 0.01), increased hepatic triglyceride content (p = 0.04), and impaired myocardial energetics (p = 0.04). Although cardiac structural changes, steatosis, and energetics were similar between the T2D groups, epicardial fat (p = 0.04), hepatic triglyceride (p = 0.01), and insulin resistance (p = 0.03) were higher in Ob-T2D. Epicardial fat, hepatic triglyceride, and insulin resistance correlated negatively with systolic strain and diastolic strain rates, which were only significantly impaired in Ob-T2D (p < 0.001 and p = 0.006, respectively). Fibroinflammatory liver disease (elevated cT1) was only evident in Ob-T2D patients. cT1 correlated with hepatic and epicardial fat (p < 0.001 and p = 0.01, respectively).

CONCLUSIONS

Irrespective of body mass index, diabetes is related to significant abnormalities in cardiac structure, energetics, and cardiac and hepatic steatosis. Obese patients with T2D show a greater propensity for ectopic and visceral fat deposition.

Cardiovascular Disease and Myocardial Abnormalities in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in many developed countries, affecting an estimated 30 % of the adult population. In this updated clinical review, we summarize the current knowledge regarding the strong association between NAFLD and the risk of coronary heart disease (CHD) and other functional, structural, and arrhythmic cardiac complications (e.g., left ventricular dysfunction, heart valve diseases and atrial fibrillation). We also briefly discuss the putative biological mechanisms linking NAFLD with these important extra-hepatic complications. To date, a large body of evidence has suggested that NAFLD is not simply a marker of CHD and other functional, structural, and arrhythmic cardiac complications, but also may play a part in the development and progression of these cardiac complications. The clinical implication of these findings is that patients with NAFLD may benefit from more intensive surveillance and early treatment interventions aimed at decreasing the risk of CHD and other cardiac and arrhythmic complications.

The Presence of White Matter Lesions Is Associated With the Fibrosis Severity of Nonalcoholic Fatty Liver Disease

We tested whether nonalcoholic fatty liver disease (NAFLD) and/or its histological severity are associated with vascular white matter lesions (WML) in patients with biopsy-proven NAFLD and in non-NAFLD controls. Data were recorded in 79 consecutive biopsy-proven NAFLD, and in 82 controls with normal ALT and no history of chronic liver diseases, without ultrasonographic evidence of steatosis and liver stiffness value <6 KPa. All subjects underwent magnetic resonance assessment and WML were classified according to the Fazekas score as absent (0/III), or present (mild I/III; moderate II/III, and severe I/III). For the purpose of analyses, all controls were considered without NASH and without F2-F4 liver fibrosis. WML were found in 26.7% of the entire cohort (43/161), of moderate-severe grade in only 6 cases. The prevalence was similar in NAFLD versus no-NAFLD (29.1% vs 24.3%; P = 0.49), but higher in NASH vs no-NASH (37.7% vs 21.2%, P = 0.02) and F2-F4 vs F0-F1 fibrosis (47.3% vs 20.3%, P = 0.001). In both the entire cohort and in NAFLD, only female gender (OR 4.37, 95% CI: 1.79-10.6, P = 0.001; and OR 5.21, 95% CI: 1.39-19.6, P = 0.01), age > 45 years (OR 3.09, 95% CI: 1.06-9.06, P = 0.03; and OR 11.1, 95% CI: 1.14-108.7, P = 0.03), and F2-F4 fibrosis (OR 3.36, 95% CI: 1.29-8.73, P = 0.01; and OR 5.34, 95% CI: 1.40-20.3, P = 0.01) were independently associated with WML (mostly of mild grade) by multivariate analysis. Among NAFLD, the prevalence of WML progressively increased from patients without (1/18; 5.5%), or with 1 (1/17, 5.8%), to those with 2 (9/30; 30%) and further to those with 3 (12/14; 85.7%) risk factors. The presence of WML is not associated with NAFLD, but with metabolic diseases in general, and fibrosis severity of NAFLD. Clinical implications of this issue need to be assessed by longitudinal studies.

Research advances in the relationship between nonalcoholic fatty liver disease and atherosclerosis

Nonalcoholic fatty liver disease (NAFLD) is a metabolic stress-induced liver disease that is closely related not only to genetic susceptibility but also to insulin resistance and highly linked with metabolic syndrome. In recent years, the prevalence of NAFLD has increased rapidly, paralleling the epidemic of type 2 diabetes mellitus and obesity leading to cardiovascular disease. It has been demonstrated that NAFLD is highly associated with atherosclerosis. With recently gained knowledge, it appears that NAFLD may induce insulin resistance, dyslipidemia, oxidative stress, inflammation, and fluctuation of adipokines associated with atherosclerosis. In this review, we aimed to summarize recent discoveries related to both NAFLD and atherosclerosis, and to identify possible mechanisms linking them.

Heat Killed Lactobacillus reuteri GMNL-263 Reduces Fibrosis Effects on the Liver and Heart in High Fat Diet-Hamsters via TGF-β Suppression

Obesity is one of the major risk factors for nonalcoholic fatty liver disease (NAFLD), and NAFLD is highly associated with an increased risk of cardiovascular disease (CVD). Scholars have suggested that certain probiotics may significantly impact cardiovascular health, particularly certain Lactobacillus species, such as Lactobacillus reuteri GMNL-263 (Lr263) probiotics, which have been shown to reduce obesity and arteriosclerosis in vivo. In the present study, we examined the potential of heat-killed bacteria to attenuate high fat diet (HFD)-induced hepatic and cardiac damages and the possible underlying mechanism of the positive effects of heat-killed Lr263 oral supplements. Heat-killed Lr263 treatments (625 and 3125 mg/kg-hamster/day) were provided as a daily supplement by oral gavage to HFD-fed hamsters for eight weeks. The results show that heat-killed Lr263 treatments reduce fatty liver syndrome. Moreover, heat-killed Lactobacillus reuteri GMNL-263 supplementation in HFD hamsters also reduced fibrosis in the liver and heart by reducing transforming growth factor β (TGF-β) expression levels. In conclusion, heat-killed Lr263 can reduce lipid metabolic stress in HFD hamsters and decrease the risk of fatty liver and cardiovascular disease.

Composite prognostic models across the non-alcoholic fatty liver disease spectrum: Clinical application in developing countries

Heterogeneity in clinical presentation, histological severity, prognosis and therapeutic outcomes characteristic of non-alcoholic fatty liver disease (NAFLD) necessitates the development of scientifically sound classification schemes to assist clinicians in stratifying patients into meaningful prognostic subgroups. The need for replacement of invasive liver biopsies as the standard method whereby NAFLD is diagnosed, graded and staged with biomarkers of histological severity injury led to the development of composite prognostic models as potentially viable surrogate alternatives. In the present article, we review existing scoring systems used to (1) confirm the presence of undiagnosed hepatosteatosis; (2) distinguish between simple steatosis and NASH; and (3) predict advanced hepatic fibrosis, with particular emphasis on the role of NAFLD as an independent cardio-metabolic risk factor. In addition, the incorporation of functional genomic markers and application of emerging imaging technologies are discussed as a means to improve the diagnostic accuracy and predictive performance of promising composite models found to be most appropriate for widespread clinical adoption.

Epicardial fat, cardiac geometry and cardiac function in patients with non-alcoholic fatty liver disease: association with the severity of liver disease

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) has been associated with increased cardiovascular risk, including coronary artery disease and cardiac dysfunction. In addition, recent evidence highlighted the possible role of epicardial fat as a new cardiometabolic risk factor. We tested the correlation between epicardial fat, alterations in cardiac geometry and function, and severity of liver damage, in patients with biopsy-proven NAFLD.

METHODS

The anthropometric, biochemical and metabolic features were recorded in 147 consecutive biopsy-proven NAFLD cases (Kleiner score). Epicardial fat thickness was measured by echocardiography.

RESULTS

Epicardial fat was higher in patients with severe vs. milder fibrosis (8.5 ± 3.0 vs. 7.2 ± 2.3 mm; p=0.006); this association was maintained at multivariate logistic regression analysis (OR 1.22, 95%C.I. 1.01-1.47; p=0.04) after correction for gender, age >50 years, visceral obesity, IFG/diabetes, non-alcoholic steatohepatitis and severe steatosis. Of note, 37.1% of patients with epicardial fat >7 mm (median value) had severe liver fibrosis, compared to 18.3% of the cases with lower epicardial fat (p=0.01). As for echocardiographic indices, after adjusting for cardiometabolic confounders, diastolic posterior-wall thickness (p=0.01), left ventricular mass (p=0.03), relative wall thickness (p=0.02), and left atrial volume (0.04), as well as ejection fraction (p=0.004), lower lateral TDI e' (p=0.009), E/A ratio (0.04) (cardiac geometry alterations and diastolic dysfunction) were linked to severe liver fibrosis.

CONCLUSIONS

In patients with NAFLD, a higher epicardial fat thickness is associated with the severity of liver fibrosis, in keeping with a possible pathogenic role of ectopic fat depots in whole body organ damage. In addition, morphological and functional cardiac alterations are more pronounced according to the severity of fibrosis. Further studies are needed to validate our results.

Association between liver fibrosis and coronary heart disease risk in patients with nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is being increasingly recognized as the most common cause of chronic liver disease worldwide. It has been shown that NAFLD in adults is associated with increased risk of coronary heart disease (CHD). Because of the limitations of liver biopsy, noninvasive scoring indexes such as the NAFLD fibrosis score (NFS) were developed. The Framingham risk score (FRS) provides an estimate of CHD risk. In our study we aimed to investigate whether the severity of liver fibrosis estimated with the NFS is associated with a higher risk of CHD among individuals with ultrasonography-diagnosed NAFLD.

STUDY

A total of 155 patients and controls (81 patients with NAFLD and 74 controls) with ages ranging from 18 to 70 years were enrolled in this cross-sectional prospective study. Demographic, anthropometric, clinical, and laboratory data were obtained from each individual. The NAFLD patients were divided into subgroups on the basis of the severity of fatty liver. The FRS and NFS were adopted to predict the risk of CHD and the severity of hepatic fibrosis.

RESULTS

In our study, we found that the FRS was higher in NAFLD patients than in controls (P<0.05). According to the FRS category, NFSs were higher in the intermediate/high probability CHD risk group in NAFLD (P<0.05). In multiple models, only age, sex, cholesterol, and HDL were independently associated with intermediate/high CHD risk (P<0.05). We also found a positive correlation between the NFS and the FRS (r=0.373, P<0.001). The optimum NFS cutoff point for identifying intermediate/high CHD risk in NAFLD patients was -2.1284, with a sensitivity and specificity of 95.20 and 48.30%, respectively. The predictive performance of the NFS in the determination of intermediate/high CHD risk in NAFLD patients was found to be 72% based on the area under the curve value.

CONCLUSION

The FRS is associated with the NFS in NAFLD. The assessment of liver fibrosis may be useful for the risk stratification of CHD in the absence of liver biopsy in clinical practice.

Nonalcoholic fatty liver disease and vascular disease: State-of-the-art

Nonalcoholic fatty liver disease (NAFLD), the most common of chronic liver disease in Western Country, is closely related to insulin resistance and oxidative stress and includes a wide spectrum of liver diseases ranging from steatosis alone, usually a benign and non-progressive condition, to nonalcoholic steatohepatitis (NASH), which may progress to liver fibrosis and cirrhosis. NAFLD is considered the hepatic manifestation of the metabolic syndrome with which shares several characteristics, however recent data suggest that NAFLD is linked to increased cardiovascular risk independently of the broad spectrum of risk factors of metabolic syndrome. Accumulating evidence suggests that the clinical burden of NAFLD is not restricted to liver-related morbidity and mortality, with the majority of deaths in NAFLD patients related to cardiovascular disease and cancer and not to the progression of liver disease. Retrospective and prospective studies provide evidence of a strong association between NAFLD and subclinical manifestation of atherosclerosis (increased intima-media thickness, endothelial dysfunction, arterial stiffness, impaired left ventricular function and coronary calcification). A general agreement emerging from these studies indicates that patients with NASH are at higher risk of cardiovascular diseases than those with simple steatosis, emphasizing the role of chronic inflammation in the pathogenesis of atherosclerosis of these patients. It is very likely that the different mechanisms involved in the pathogenesis of atherosclerosis in patients with NAFLD have a different relevance in the patients according to individual genetic background. In conclusion, in the presence of NAFLD patients should undergo a complete cardiovascular evaluation to prevent future atherosclerotic complications. Specific life-style modification and aggressive pharmaceutical modification will not only reduce the progression of liver disease, but also reduce morbidity for cardiovascular disease improving overall prognosis and survival.

Risk of cardiovascular, cardiac and arrhythmic complications in patients with non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) has emerged as a public health problem of epidemic proportions worldwide. Accumulating clinical and epidemiological evidence indicates that NAFLD is not only associated with liver-related morbidity and mortality but also with an increased risk of coronary heart disease (CHD), abnormalities of cardiac function and structure (e.g., left ventricular dysfunction and hypertrophy, and heart failure), valvular heart disease (e.g., aortic valve sclerosis) and arrhythmias (e.g., atrial fibrillation). Experimental evidence suggests that NAFLD itself, especially in its more severe forms, exacerbates systemic/hepatic insulin resistance, causes atherogenic dyslipidemia, and releases a variety of pro-inflammatory, pro-coagulant and pro-fibrogenic mediators that may play important roles in the pathophysiology of cardiac and arrhythmic complications. Collectively, these findings suggest that patients with NAFLD may benefit from more intensive surveillance and early treatment interventions to decrease the risk for CHD and other cardiac/arrhythmic complications. The purpose of this clinical review is to summarize the rapidly expanding body of evidence that supports a strong association between NAFLD and cardiovascular, cardiac and arrhythmic complications, to briefly examine the putative biological mechanisms underlying this association, and to discuss some of the current treatment options that may influence both NAFLD and its related cardiac and arrhythmic complications.