Cardiac abnormalities as a new manifestation of nonalcoholic fatty liver disease: echocardiographic and tissue Doppler imaging assessment

NASH triggers cardiometabolic HFpEF in aging mice

Both heart failure with preserved ejection fraction (HFpEF) and non-alcoholic fatty liver disease (NAFLD) develop due to metabolic dysregulation, has similar risk factors (e.g., insulin resistance, systemic inflammation) and are unresolved clinical challenges. Therefore, the potential link between the two disease is important to study. We aimed to evaluate whether NASH is an independent factor of cardiac dysfunction and to investigate the age dependent effects of NASH on cardiac function. C57Bl/6 J middle aged (10 months old) and aged mice (24 months old) were fed either control or choline deficient (CDAA) diet for 8 weeks. Before termination, echocardiography was performed. Upon termination, organ samples were isolated for histological and molecular analysis. CDAA diet led to the development of NASH in both age groups, without inducing weight gain, allowing to study the direct effect of NASH on cardiac function. Mice with NASH developed hepatomegaly, fibrosis, and inflammation. Aged animals had increased heart weight. Conventional echocardiography revealed normal systolic function in all cohorts, while increased left ventricular volumes in aged mice. Two-dimensional speckle tracking echocardiography showed subtle systolic and diastolic deterioration in aged mice with NASH. Histologic analyses of cardiac samples showed increased cross-sectional area, pronounced fibrosis and Col1a1 gene expression, and elevated intracardiac CD68+ macrophage count with increased Il1b expression. Conventional echocardiography failed to reveal subtle change in myocardial function; however, 2D speckle tracking echocardiography was able to identify diastolic deterioration. NASH had greater impact on aged animals resulting in cardiac hypertrophy, fibrosis, and inflammation.

Non-Alcoholic Fatty Liver Disease and Echocardiographic Parameters of Left Ventricular Diastolic Function: A Systematic Review and Meta-Analysis

The cardiovascular implications of non-alcoholic fatty liver disease (NAFLD) have been associated with heart failure with preserved ejection fraction (HFpEF). The purpose of this review was to conduct a bibliographic search regarding the correlation between NAFLD and the echocardiographic parameters of left ventricular diastolic function. A systematic literature search was conducted in PubMed and Embase for original research data reporting on the association of NAFLD with diastolic function markers [E/e', left atrial volume index (LAVi), left ventricular mass index (LVMi)]. Meta-analysis was performed using the meta and dmetar packages in R studio v.1.4.1106, with p < 0.05 values being considered significant. Results are expressed as the standardized mean difference (SMD) for continuous variables and as the odds ratio (OR) for categorical variables, with respective 95% confidence intervals (CI). Heterogeneity between studies was expressed with index Ι2. From the preliminary search, 2619 articles were found from which 31 studies were included in the final statistical analysis. The meta-analysis of 8 studies which reported on the prevalence of diastolic dysfunction showed that it was increased in patients with NAFLD (OR: 2.07, 95% CI 1.24-3.44 with p = 0.01, I2: 80% with p < 0.01). The meta-analysis of 21 studies showed significantly higher E/e' in NAFLD patients (SMD 1.02, 95% CI 0.43-1.61 with p < 0.001, I2: 97% with p < 0.001). Individuals with NAFLD had increased LAVi (SMD: 0.87, 95% CI 0.38-1.37 with p < 0.001, I2: 96% with p < 0.001) and LVMi (SMD: 0.89, 95% CI 0.31-1.48 with p = 0.003, I2: 100% with p < 0.001). To conclude, in the meta-analysis of 31 observational studies, NAFLD patients were found to have affected left ventricular diastolic function, supporting the hypothesis of NAFLD being associated with HFpEF.

Mechanisms Linking Metabolic-Associated Fatty Liver Disease (MAFLD) to Cardiovascular Disease

PURPOSE OF REVIEW

Metabolic-associated fatty liver disease (MAFLD) is a condition of fat accumulation in the liver that occurs in the majority of patients in combination with metabolic dysfunction in the form of overweight or obesity. In this review, we highlight the cardiovascular complications in MAFLD patients as well as some potential mechanisms linking MAFLD to the development of cardiovascular disease and highlight potential therapeutic approaches to treating cardiovascular diseases in patients with MAFLD.

RECENT FINDINGS

MAFLD is associated with an increased risk of cardiovascular diseases (CVD), including hypertension, atherosclerosis, cardiomyopathies, and chronic kidney disease. While clinical data have demonstrated the link between MAFLD and the increased risk of CVD development, the mechanisms responsible for this increased risk remain unknown. MAFLD can contribute to CVD through several mechanisms including its association with obesity and diabetes, increased levels of inflammation, and oxidative stress, as well as alterations in hepatic metabolites and hepatokines. Therapies to potentially treat MAFLD-induced include statins and lipid-lowering drugs, glucose-lowering agents, antihypertensive drugs, and antioxidant therapy.

Decreased liver-to-spleen ratio in low-dose computed tomography as a biomarker of fatty liver disease reflects risk for myocardial ischaemia

Aims

A strong association between fatty liver disease (FLD) and coronary artery disease is consistently reported. Our aim was to evaluate whether FLD diagnosed using low-dose non-contrast computed tomography (LDCT), as a by-product of myocardial perfusion imaging (MPI), is associated with myocardial ischaemia or left ventricular function parameters.

Methods and results

We analysed 742 patients who had undergone MPI using single photon emission computed tomography (SPECT) and LDCT. A liver-to-spleen ratio (in Hounsfield units) of <1 was defined as FLD. Myocardial ischaemia was defined as a summed difference score (SDS) ≥3. Left ventricular size and systolic function were assessed from the electrocardiogram-gated SPECT. FLD patients were younger (63 vs. 68 years) and had a higher body mass index (34.6 vs. 29.0 kg/m2) and a higher SDS (2.65 vs. 1.63), P < 0.001 for all. Independently of several possible confounding factors including traditional risk factors, patients with FLD had a 1.70-fold risk of ischaemia (95% confidence interval 1.11-2.58, P = 0.014). Left ventricular end-diastolic volume (109 vs. 109 mL) and ejection fraction (61 vs. 61%) were comparable in those with and without FLD (non-significant for both).

Conclusions

With the help of LDCT, it is possible to identify FLD, which is associated with an increased risk of myocardial ischaemia. Therefore, evaluation of FLD from LDCT is recommended along with MPI.

Fatty Liver Disease-Alcoholic and Non-Alcoholic: Similar but Different

In alcohol-induced liver disease (ALD) and in non-alcoholic fatty liver disease (NAFLD), there are abnormal accumulations of fat in the liver. This phenomenon may be related to excessive alcohol consumption, as well as the combination of alcohol consumption and medications. There is an evolution from simple steatosis to steatohepatitis, fibrosis and cirrhosis leading to hepatocellular carcinoma (HCC). Hepatic pathology is very similar regarding non-alcoholic fatty liver disease (NAFLD) and ALD. Initially, there is lipid accumulation in parenchyma and progression to lobular inflammation. The morphological changes in the liver mitochondria, perivenular and perisinusoidal fibrosis, and hepatocellular ballooning, apoptosis and necrosis and accumulation of fibrosis may lead to the development of cirrhosis and HCC. Medical history of ethanol consumption, laboratory markers of chronic ethanol intake, AST/ALT ratio on the one hand and features of the metabolic syndrome on the other hand, may help in estimating the contribution of alcohol intake and the metabolic syndrome, respectively, to liver steatosis.

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

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

Liver Fibrosis-4 index indicates atrial fibrillation in acute ischemic stroke

Background

Non‐alcoholic fatty liver disease and particularly liver fibrosis are related to cardiovascular disease and may indicate an increased risk for atrial fibrillation (AF), but this association has not yet been systematically investigated in a cohort of ischemic stroke patients.

Methods

We analyzed data from a prospective single‐center study enrolling all consecutive ischemic stroke patients admitted to our stroke unit over a 1‐year period. All patients received a thorough etiological workup. For evaluation of liver fibrosis, we determined the Fibrosis‐4 (FIB‐4) index, a well‐established noninvasive liver fibrosis test. Laboratory results were analyzed from a uniform blood sample taken at stroke unit admission.

Results

Of 414 included patients (mean age 70.2 years, 57.7% male), FIB‐4 indicated advanced liver fibrosis in 92 (22.2%). AF as the underlying stroke mechanism was present in 28.0% (large vessel disease: 25.6%, small vessel disease: 11.4%, cryptogenic: 29.2%). Patients with FIB‐4 ≥ 2.67 had higher rates of AF (53.3% vs. 20.8%, p < 0.001), and this association remained significant after correction for established AF risk factors (odds ratio 2.53, 95% confidence interval 1.44–4.46, p = 0.001). FIB‐4 was further associated with worse functional outcome 3 months (p < 0.001) and higher mortality 4 years post‐stroke (p < 0.02), but these relationships were no longer present after correction for age and initial stroke severity. Moreover, FIB‐4 was not associated with long‐term recurrent vascular events.

Conclusions

Liver fibrosis assessed by the FIB‐4 index is independently associated with AF in acute ischemic stroke patients. Further studies should evaluate whether adding the FIB‐4 index to AF risk scores increases their precision.

Association of Non-Alcoholic Fatty Liver Disease and Hepatic Fibrosis with Epicardial Adipose Tissue Volume and Atrial Deformation Mechanics in a Large Asian Population Free from Clinical Heart Failure

Non-alcoholic fatty liver disease (NAFLD) and cardiovascular disease share several cardiometabolic risk factors. Excessive visceral fat can manifest as ectopic fat depots over vital organs, such as the heart and liver. This study assessed the associations of NAFLD and liver fibrosis with cardiac structural and functional disturbances. We assessed 2161 participants using ultrasound, and categorized them as per the NAFLD Fibrosis Score into three groups: (1) non-fatty liver; (2) fatty liver with low fibrosis score; and (3) fatty liver with high fibrosis score. Epicardial fat volume (EFV) was measured through multidetector computed tomography. All participants underwent echocardiographic study, including tissue Doppler-based E/e’ ratio and speckle tracking-based left ventricular global longitudinal strain, peak atrial longitudinal strain (PALS), and atrial longitudinal strain rates during systolic, early and late-diastolic phases (ALSRsyst, ALSRearly. ALSRlate). Larger EFV, decreased e’ velocity, PALS, ALSRsyst, and ALSRearly, along with elevated E/e’ ratio, were seen in all groups, especially in those with high fibrosis scores. After multivariate adjustment for traditional risk factors and EFV, fibrosis scores remained significantly associated with elevated E/e’ ratio, LA stiffness, and decreased PALS (β: 0.06, 1.4, −0.01, all p < 0.05). Thus, NAFLD is associated with LV diastolic dysfunction and subclinical changes in LA contractile mechanics.

Non-alcoholic fatty liver disease association with structural heart, systolic and diastolic dysfunction: a meta-analysis

OBJECTIVE

Several studies have documented a relationship between non-alcoholic fatty liver disease (NAFLD) and structural heart disease, particularly diastolic function. This meta-analysis will be the first to examine the echocardiographic-derived cardiac function and structural characteristics in NAFLD patients, and its association with liver disease severity and metabolic profile.

METHODS

Medline and Embase were searched and pairwise meta-analysis was conducted in DerSimonian and Laird to obtain the odds ratio (OR) and mean difference (MD) for dichotomous and continuous variables, respectively, to compare the effects of NAFLD on the echocardiography parameters.

RESULTS

Forty-one articles involving 33,891 patients underwent echocardiography. NAFLD patients had worse systolic indices with lower ejection fraction (EF, MD: - 0.693; 95% CI: - 1.112 to - 0.274; p = 0.001), and worse diastolic indices with higher E/e' (MD: 1.575; 95% CI: 0.924 to 2.227; p < 0.001) compared to non-NAFLD patients. NAFLD patients displayed increased left ventricular mass (LVM, MD: 34.484; 95% CI: 26.236 to 42.732; p < 0.001) and epicardial adipose thickness (EAT, MD: 0.1343; 95% CI: 0.055 to 0.214; p = 0.001). An increased severity of NAFLD was associated with worse diastolic indices (decreased E/A ratio, p = 0.007), but not with systolic indices.

CONCLUSIONS

NAFLD is associated with impaired systolic and diastolic function with changes in cardiac structure. Concomitant metabolic risk factors and liver disease severity are independently associated with worsening systolic and diastolic function.

Cerebral hemodynamics in the non-alcoholic fatty liver

INTRODUCTION AND OBJECTIVES

The association between non-alcoholic fatty liver disease and cerebral hemodynamics arises from cardiovascular damage mechanisms such as endothelial dysfunction, arterial wall increased stiffness, high thickness of the intimate index of the internal carotid artery, left ventricular hypertrophy, left diastolic dysfunction, calcification coronary arteries and increased epicardial fat. The multidirectional relationship between systemic inflammation and lipid metabolism constitutes a common and simultaneous mechanism that causes vascular damage. This study aims to provide insight into the relationship between non-alcoholic fatty liver disease and the function of systemic circulation and cerebral circulation using Doppler ultrasound.

PATIENTS AND METHODS

Is an observational, cross-sectional, prospective, comparative study conducted at Medica Sur Hospital. Thirty-five patients were selected consecutively. The patients consulted neurological service for various symptoms without severity criteria, such as vertigo, primary headache and balance disturbances.

RESULTS

There is a difference in the variables mean of the right MCA PI (p = 0.023), left MCA PI" (p = 0.004), and left VA PI (p = 0.036) between the control and NAFLD groups. The correlation analysis between these variables and the CAP showed a positive correlation of the three variables with the CAP, "right MCA PI" (r = 0.384), left MCA PI "(r = 0.509) and" left VA PI " (r = 0.551).

CONCLUSIONS

This study demonstrates a subclinical process of the middle cerebral artery in subjects with NAFLD, which suggests it may be involved in the disease development and points the need to make decisions for this liver manifestation prevention and treatment.

Significant Association Between Left Ventricular Diastolic Dysfunction, Left Atrial Performance and Liver Stiffness in Patients with Metabolic Syndrome and Non-Alcoholic Fatty Liver Disease

PURPOSE

The constitutive elements of the metabolic syndrome (MetS) are linked with both non-alcoholic fatty liver disease (NAFLD) and cardiovascular disease. Controlled attenuation parameter (CAP), and vibration controlled transient elastography (VCTE), are able to detect and quantify NAFLD, while conventional and two-dimensional speckle tracking echocardiography (2D-STE) is capable to identify subclinical changes in cardiac function. We wanted to evaluate whether there is any correspondence between left ventricular (LV) diastolic dysfunction and different degrees of liver steatosis and fibrosis in MetS subjects with NAFLD.

PATIENTS AND METHODS

A total of 150 adult subjects having MetS and a normal left ventricular (LV) systolic function were recorded in the study, while 150 age- and sex- matched adults without MetS were enrolled as controls. NAFLD was established by VCTE and CAP. The left heart systolic and diastolic function was evaluated by conventional and 2D-ST echocardiography. Left atrial (LA) stiffness was calculated as the ratio between the E/A ratio and the LA reservoir-strain.

RESULTS

In univariate regression analysis, the variables associated with LV diastolic dysfunction in MetS patients were: liver steatosis grade ≥2, liver fibrosis grade ≥2, the longitudinal LA peak strain during the reservoir phase, the LA strain rate during ventricular contraction and the LA stiffness. In multivariate logistic regression, two variables were selected as independent predictors of LV diastolic dysfunction, namely the liver stiffness (P=0.0003) and the LA stiffness (P<0.0001). LA stiffness predicted subclinical LV diastolic dysfunction in MetS patients with a sensitivity of 45% and a specificity of 96% when using a cut-off value >0.38, and was significantly correlated with liver steatosis stage ≥2 and liver fibrosis stage ≥2.

CONCLUSION

The present study confirms the association between liver stiffness, LA stiffness and LV diastolic dysfunction in MetS patients. Our study suggests that liver elastography and 2D-STE should become habitual assessments in MetS patients.

Nonalcoholic fatty liver disease, diastolic dysfunction, and impaired myocardial glucose uptake in patients with type 2 diabetes

AIMS

To investigate whether degree of nonalcoholic fatty liver disease (NAFLD) is associated with myocardial dysfunction related to impaired myocardial glucose uptake in patients with type 2 diabetes.

MATERIALS AND METHODS

In total, 131 patients with type 2 diabetes from a tertiary care hospital were included in this study. Myocardial glucose uptake was assessed using [¹⁸ F]-fluorodeoxyglucose-positron emission tomography. Hepatic steatosis and fibrosis were determined using transient liver elastography. Echocardiography was performed to evaluate cardiac structure and function.

RESULTS

Patients with NAFLD had cardiac diastolic dysfunction with higher left ventricular filling pressure (E/e' ratio) and left atrial (LA) volume index than patients without NAFLD (all P < 0.05). Hepatic steatosis correlated with E/e' ratio and LA volume index, and hepatic fibrosis also correlated with E/e' ratio (all P < 0.05). Even after adjusting for confounding factors, a higher degree of hepatic steatosis (r² = 0.409, P = 0.041) and a higher degree of fibrosis (r² = 0.423, P = 0.009) were independent contributing factors to a higher E/e' ratio. Decreased myocardial glucose uptake was associated with a higher degree of steatosis (P for trend = 0.084) and fibrosis (P for trend = 0.012). At the same time, decreased myocardial glucose uptake was an independent contributing factor for a higher E/e' ratio (r² = 0.409; P = 0.040).

CONCLUSIONS

Hepatic steatosis and fibrosis were significantly associated with diastolic heart dysfunction in patients with type 2 diabetes coupled with impaired myocardial glucose uptake.

Non-alcoholic fatty liver disease and heart failure with preserved ejection fraction: from pathophysiology to practical issues

The prevalence of non-alcoholic fatty liver disease (NAFLD) in heart failure (HF) preserved left ventricular ejection fraction (HFpEF) patients could reach 50%. Therefore, NAFLD is considered an emerging risk factor. In 20% of NAFLD patients, the condition progresses to non-alcoholic steatohepatitis (NASH), the aggressive form of NAFLD characterized by the development of fibrosis in the liver, leading to cirrhosis. The purpose of this review is to provide an overview of the relationships between NAFLD and HFpEF and to discuss its impact in clinical setting. Based on international reports published during the past decade, there is growing evidence that NAFLD is associated with an increased incidence of cardiovascular diseases, including impaired cardiac structure and function, arterial hypertension, endothelial dysfunction, and early carotid atherosclerosis. NAFLD and HFpEF share common risk factors, co-morbidities, and cardiac outcomes, in favour of a pathophysiological continuum. Currently, NAFLD and NASH are principally managed with non-specific therapies targeting insulin resistance like sodium-glucose co-transporter-2 inhibitors and liraglutide, which can effectively treat hepatic and cardiac issues. Studies including HFpEF patients are ongoing. Several specific NAFLD-oriented therapies are currently being developed either alone or as combinations. NAFLD diagnosis is based on a chronic elevation of liver enzymes in a context of metabolic syndrome and insulin resistance, with fibrosis scores being available for clinical practice. In conclusion, identifying HF patients at risk of NAFLD is a critically important issue. As soon as NAFLD is confirmed and its severity determined, patients should be proposed a management focused on symptoms and co-morbidities.

Three-dimensional speckle tracking echocardiography for early detection of left ventricular dysfunction in children with non-alcoholic fatty liver diseases

OBJECTIVES

To detect early left ventricular dysfunction in children with non-alcoholic fatty liver disease using three-dimensional speckle tracking echocardiography.

METHODS

Forty obese children with non-alcoholic fatty liver disease were included as group I. Another 40 obese children without non-alcoholic fatty liver disease of matched age, sex, and weight were included as group II. Forty healthy controls of matched age and sex served as a control group. Anthropometric measurements, laboratory investigations, and echocardiographic examinations including three-dimensional speckle tracking echocardiography were measured for all included children.

RESULTS

Abnormal lipid profile was detected in children with non-alcoholic fatty liver disease. Troponin I levels were significantly higher in children with non-alcoholic fatty liver disease compared to obese children without non-alcoholic fatty liver disease and to healthy controls. Three-dimensional speckle tracking echocardiography examination revealed a significant reduction of left ventricular global longitudinal strain, circumferential strain, radial strain, and area strain in children with non-alcoholic fatty liver disease inspite of normal left ventricular fraction shortening measured by conventional echocardiography. All strains were negatively correlated with the grade of non-alcoholic fatty liver disease.

CONCLUSION

Non-alcoholic fatty liver disease is associated with subclinical left ventricular dysfunction. Three-dimensional speckle tracking echocardiography can be helpful in identifying early left ventricular dysfunction in children with non-alcoholic fatty liver disease even in the presence of normal left ventricular ejection fraction.

Assessment of Left Ventricular Diastolic Function in Young Adults with Nonalcoholic Fatty Liver Disease

There is strong evidence that, in addition to increasing the risk of cirrhosis as well as hepatocellular carcinoma, nonalcoholic liver disease represents an independent risk factor for different diseases including cardiovascular and chronic kidney disease and also type 2 diabetes. Objective: to assess whether nonalcoholic fatty liver disease is associated with diastolic dysfunction of the left ventricle, independent of other classic risk factors. Methods: we included 79 patients aged 15-45, diagnosed with non-alcoholic liver disease, and a group of 80 healthy people in the same age group. We assessed left ventricular diastolic function using Doppler pulsed wave transmitral flow and Tissue Doppler Imaging methods. Results: there were lower velocities of E and e’ wave, a decrease in E/A ratio and an increase in E/e’ ratio in the group of patients with hepatic steatosis and in those with associated diabetes compared to the control group, but not the same was observed when comparing patients with steatosis alone vs. hepatic steatosis and associated diabetes mellitus. Conclusion: nonalcoholic steatosis is linked to echocardiographic features of early diastolic dysfunction that are present in patients suffering from diabetes.

Evaluation of subclinical cardiac damage in biopsy-proven nonalcoholic fatty liver disease: a systematic review and meta-analysis

Background

Data on the association of nonalcoholic fatty liver disease (NAFLD) with subclinical cardiac damage are scanty. We performed a systematic review to provide comprehensive information on subclinical cardiac alterations among NAFLD subjects.

Methods

PubMed and the Cochrane Library were searched to identify studies comparing subclinical cardiac damage between NAFLD and healthy adults. We also searched PROSPERO to check for any similar meta-analysis in progress in order to avoid duplication with our study. Conference abstracts and the reference lists of relevant studies and systematic reviews were perused. The Newcastle-Ottawa quality assessment scale for case-control and cohort studies were used to assess study quality.

Results

Seven studies were finally included in the meta-analysis (1 cross sectional and 6 case-control), with a total of 602 individuals (362 patients with NAFLD). Epicardial fat thickness were statistically significantly higher in patients with NAFLD than in controls (mean difference [MD] 1.17, 95% confidence interval [CI] 0.45-1.89, I²=89%). Global longitudinal strain was lower in NAFLD, to a statistically significant degree (MD -3.17, 95%CI -5.09 to -1.24, I²=89%). However, significant heterogeneity of the findings was observed.

Conclusions

Our findings indicate that NAFLD is related to subclinical cardiac damage. Further studies with a larger number of biopsy-proven NAFLD patients are needed to confirm this finding. Preventive and therapeutic interventions early in the course of the disease might decrease morbidity in this high-risk patient group.

Fatty liver index and left ventricular mass: prospective associations from two independent cohorts

OBJECTIVES

Heart disease is the most common cause of death in patients with nonalcoholic fatty liver disease (NAFLD). Emerging data have shown that NAFLD may affect subclinical myocardial remodeling, mainly left ventricular hypertrophy; however, evidence from the prospective studies is still lacking.

METHODS

Prospective analyses were performed to investigate the association of fatty liver index (FLI) with left ventricular mass (LVM) among 1962 participants from the Bogalusa Heart Study (BHS, 1995-2010) and 1547 participants from the Cardiovascular Risk in Young Finns Study (YFS, 2001-2011) free of cardiovascular diseases (CVD) at baseline. LVM was assessed by two-dimensional guided M-mode echocardiography and indexed (LVMI) to body height (m2.7). Multivariable regression models were applied after adjustment for traditional CVD risk factors.

RESULTS

In both cohorts, we observed significant and positive associations between FLI and LVM (BHS: β=0.59, P < 0.001; YFS: β=0.41, P < 0.001) and LVMI (BHS: β=0.14, P < 0.001; YFS: β=0.09, P < 0.001). In addition, we found that the relationship between FLI and LVMI was stronger in women than men (BHS: P-interaction = 0.01; YFS: P-interaction < 0.01); and the relationship between FLI and LVM/LVMI was stronger in black than white individuals (LVM: P-interaction = 0.02; LVMI: P-interaction = 0.04). Moreover, we found that the associations of FLI with LVM and LVMI were attenuated by high physical activity, especially in BHS (P-interaction = 0.02).

CONCLUSION

Our findings from two independent prospective cohorts indicate that FLI is positively associated with LVM/LVMI, independent of traditional cardiovascular risk factors. Such relationships are more pronounced among women and black individuals and are attenuated by high physical activity.

Extrahepatic Manifestations of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease and encompasses a spectrum of pathology from simple steatosis to inflammation and significant fibrosis that leads to cirrhosis. NAFLD and its comorbid conditions extend well beyond the liver. It is a multisystemic clinical disease entity with extrahepatic manifestations such as cardiovascular disease, type 2 diabetes, chronic kidney disease, hypothyroidism, polycystic ovarian syndrome, and psoriasis. Indeed, the most common causes of mortality in subjects with NAFLD are cardiovascular disease, followed by malignancies and then liver-related complications as a distant third. This review focuses on several of the key extrahepatic manifestations of NAFLD and areas for future investigation. Clinicians should learn to screen and initiate treatment for these extrahepatic manifestations in a prompt and timely fashion before they progress to end-organ damage.

The association of non-alcoholic fatty liver disease and cardiac structure and function-Framingham Heart Study

BACKGROUND & AIMS

Non-alcoholic fatty liver disease confers increased risk for cardiovascular disease, including heart failure (HF), for reasons that remain unclear. Possible pathways could involve an association of liver fat with cardiac structural or functional abnormalities even after accounting for body size.

METHODS

We analysed N = 2356 Framingham Heart Study participants (age 52 ± 12 years, 52% women) who underwent echocardiography and standardized computed tomography measures of liver fat.

RESULTS

In cross-sectional multivariable regression models adjusted for age, gender, cohort and cardiovascular risk factors, liver fat was positively associated with left ventricular (LV) mass (β = 1.45; 95% confidence interval (CI): 0.01, 2.88), LV wall thickness (β = 0.01; 95% CI: 0.00, 0.02), mass volume ratio (β = 0.02; 95% CI 0.01, 0.03), mitral peak velocity (E) (β = 0.83; 95% CI 0.31, 1.36) and LV filling pressure (E/e' ratio) (β = 0.16; 95% CI 0.09, 0.23); and inversely associated with global systolic longitudinal strain (β = 0.20, 95% CI 0.07, 0.33), diastolic annular velocity (e') (β = -0.12; 95% CI - 0.22, -0.03), and E/A ratio (β = -0.01; 95% CI - 0.02, -0.00). After additional adjustment for body mass index (BMI), statistical significance was attenuated for all associations except for that of greater liver fat with increased LV filling pressure, a possible precursor to HF (β = 0.11; 95% CI 0.03, 0.18).

CONCLUSION

Increased liver fat was associated with multiple subclinical cardiac dysfunction measures, with most of associations mediated by obesity. Interestingly, the association of liver fat and LV filling pressure was only partially mediated by BMI, suggesting a possible direct effect of liver fat on LV filling pressure. Further confirmatory studies are needed.

Impact of Nonalcoholic Fatty Liver Disease on Arrhythmia Recurrence Following Atrial Fibrillation Ablation

OBJECTIVES

This study sought to investigate the association between nonalcoholic fatty liver disease (NAFLD) and arrhythmia recurrence following atrial fibrillation ablation; and to examine the impact of NAFLD stage on outcomes.

BACKGROUND

Metabolic derangements, including obesity and diabetes, are associated with incident and recurrent atrial fibrillation (AF), in addition to the development of NAFLD.

METHODS

This was a retrospective study of 267 consecutive patients undergoing AF ablation, 89 of whom were diagnosed with NAFLD prior to ablation and matched in a 2:1 manner based on age, sex, body mass index, ejection fraction, and AF type with 178 patients without NAFLD. Patients were monitored for arrhythmia recurrence during a mean follow-up of 29 months.

RESULTS

Recurrent arrhythmia was observed in 50 (56%) patients with NAFLD compared with 37 (21%) without NAFLD. Epicardial fat volume was measured on computed tomography and was significantly higher among those with NAFLD (248 ± 125 ml vs. 223 ± 97 ml; p = 0.01). On multivariable models adjusting for sleep apnea, body mass index, heart failure, AF type, and left atrial size, NAFLD was independently associated with increased rates of arrhythmia recurrence (hazard ratio: 3.010; 95% confidence interval: 1.980 to 4.680; p < 0.0001).

CONCLUSIONS

NAFLD is associated with significantly increased arrhythmia recurrence rates following AF ablation. Identification and reversal, where possible, may result in improved arrhythmia-free survival.

Prevalence and staging of non-alcoholic fatty liver disease among patients with heart failure with preserved ejection fraction

Insulin resistance and altered energy metabolism is common in non-alcoholic fatty liver disease (NAFLD) and appears to also be associated with myocardial dysfunction. We aimed to evaluate prevalence, staging and clinical features correlated with NAFLD among patients with heart failure with preserved ejection fraction (HFpEF). Adults with HFpEF were prospectively enrolled. Demographic and clinical data were collected. NAFLD was defined based on liver biopsy, abdominal imaging or ICD-coding and the absence of other liver diseases. Descriptive, bivariate and multivariable analyses were performed. 181 patients were analyzed. The median age was 70 with 89% white, 59% female, median BMI 35.1, and 48% with diabetes. NAFLD was present in 27% of the full cohort and 50% of those with imaging. In patients with imaging, multivariable analysis identified diabetes (OR 3.38, 95% CI 1.29–8.88) and BMI (OR 1.11, 95% CI 1.04–1.19) as independent correlates of NAFLD. 54% of NAFLD patients had a NAFLD fibrosis score consistent with advanced fibrosis. Cirrhosis was present in 6.6% of patients overall and 11.5% with imaging. NAFLD patients had a higher frequency of advanced heart failure (75% vs 55%, p 0.01). NAFLD has a two-fold higher prevalence in HFpEF compared to the general population and is independently associated with BMI and diabetes. Patients with HFpEF and NAFLD also appeared to have more advanced fibrosis including cirrhosis suggesting a potential synergistic effect of cardiac dysfunction on fibrosis risk in NAFLD. This data supports consideration for evaluation of underlying liver disease in HFpEF patients.

Association between Non-Alcoholic Steatohepatitis and Left Ventricular Diastolic Dysfunction in Type 2 Diabetes Mellitus

BACKGROUND

Impaired diastolic heart function has been observed in persons with non-alcoholic fatty liver disease (NAFLD) and/or with type 2 diabetes mellitus (T2DM). However, it is unclear whether NAFLD fibrotic progression, i.e., non-alcoholic steatohepatitis, poses an independent risk for diastolic dysfunction in T2DM. We investigated the association between liver fibrosis and left ventricular (LV) diastolic dysfunction in T2DM.

METHODS

We analyzed 606 patients with T2DM, aged ≥50 years, who had undergone liver ultrasonography and pulsed-wave Doppler echocardiography. Insulin sensitivity was measured by short insulin tolerance test. Presence of NAFLD and/or advanced liver fibrosis was determined by abdominal ultrasonography and NAFLD fibrosis score (NFS). LV diastolic dysfunction was defined according to transmitral peak early to late ventricular filling (E/A) ratio and deceleration time, using echocardiography.

RESULTS

LV diastolic dysfunction was significantly more prevalent in the NAFLD versus non-NAFLD group (59.7% vs. 49.0%, P=0.011). When NAFLD was stratified by NFS, subjects with advanced liver fibrosis exhibited a higher prevalence of diastolic dysfunction (49.0%, 50.7%, 61.8%; none, simple steatosis, advanced fibrosis, respectively; P for trend=0.003). In multivariable logistic regression, liver fibrosis was independently associated with diastolic dysfunction (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.07 to 2.34; P=0.022) after adjusting for insulin resistance and cardiometabolic risk factors. This association remained significant in patients without insulin resistance (OR, 4.32; 95% CI, 1.73 to 11.51; P=0.002).

CONCLUSIONS

Liver fibrosis was associated with LV diastolic dysfunction in patients with T2DM and may be an independent risk factor for diastolic dysfunction, especially in patients without systemic insulin resistance.

Assessment of left ventricular function in type 2 diabetes mellitus patients with non-alcoholic fatty liver disease using three-dimensional speckle-tracking echocardiography

Objective:

Using three-dimensional speckle-tracking echocardiography (3D-STE), we aimed to evaluate left ventricular (LV) function in type 2 diabetes mellitus (T2DM) patients with non-alcoholic fatty liver disease (NAFLD).

Methods:

In total, 97 T2: DM patients were categorized into three groups based on hepatic ultrasonography group A (those without NAFLD, n=30), group B (those with mild NAFLD, n=32), and group C (those with moderate-to-severe NAFLD, n=35). Our conventional echocardiographic parameters included transmitral peak early and late diastolic velocity (E and A), septal and lateral early (e’) mitral annular diastolic tissue velocities, and left atrial maximum volume index (LAVImax). LV end-diastolic and -systolic volume, LV mass index (LVMI), and LV ejection fraction were measured using real-time three-dimensional echocardiography. The 3D-STE parameters included LV global radial strain (GRS), global longitudinal strain (GLS), global area strain (GAS), and global circumferential strain (GCS).

Results:

Our results showed that in group C, GCS, GRS, GLS, GAS, and septal and lateral e’ velocity decreased, whereas average E/e’ and LAVImax increased compared to groups B and A (p<0.05). Multiple linear regression analysis showed that NAFLD is independently associated with 3D-STE parameters, and glycosylated hemoglobin also has negative impacts on all LV 3D strains.

Conclusion:

When combined with conventional echocardiography, 3D-STE can assess LV function effectively in T2DM patients with NAFLD. Additionally, the severity of LV dysfunction in the moderate-to-severe NAFLD group (group C) was worse than the mild and absent NAFLD groups (groups A and B).

Association between nonalcoholic fatty liver disease and cardiac function and structure-a meta-analysis

PURPOSE

Nonalcoholic fatty liver disease is increasingly recognized as the hepatic counterpart of metabolic syndrome. It is hypothesized that structural and functional cardiac changes may be associated with this metabolic disease. We aimed to gather the existing information on the association of nonalcoholic fatty liver disease with cardiac alterations, and to evaluate a possible correlation between them.

METHODS

Systematic review of Medline searching results for original articles studying NAFLD and cardiac parameters until August 2018. A meta-analysis was conducted to each parameter of cardiac structure and function selected, using Review Manager 5.3 software. This study was conducted according to preferred reporting items for systematic reviews and meta-analysis (PRISMA).

RESULTS

A total of 16 studies met the eligibility criteria and were included in the meta-analysis. There was a significant association between nonalcoholic fatty liver disease and (1) higher left ventricle mass and ratios between left ventricle mass and both height and body surface area; (2) higher LVEDD; (3) higher left atrium diameter and ratio between left atrial volume and body surface area; (4) higher posterior wall and septum thickness; (5) lower E/A wave ratio; (6) higher E/E' ratio; (7) longer deceleration time and (8) longer relaxation time.

CONCLUSION

NAFLD associates with adverse structural alterations and cardiac dysfunction. Our results highlight the importance of identifying NAFLD in patients with metabolic dysfunction as this may represent an additional contributor to cardiovascular risk.

The association between non-alcoholic fatty liver disease and valvular heart disease

BACKGROUND

Non-alcoholic fatty liver (NAFLD) disease has become the commonest cause of end-stage liver disease. Patients with NAFLD have an increased risk of associated extrahepatic conditions, including structural and functional cardiovascular disease. Still, it is unknown if there is an association between NAFLD and valvular heart disease (VHD). The aim of this paper was to determine the association between NAFLD and VHD.

METHODS

We performed a single center retrospective study in EMMS Nazareth Hospital from April 2010 to April 2018. All patients who were diagnosed with NAFLD and who had an echocardiography performed within one year were included. Subjects age and sex-matched, who had echocardiography performed in the same period were included in the control group.

RESULTS

The mean age of the NAFLD group was 41.5±11.7 vs. 42.8±10.8 years of the control group (P=0.2). The prevalence of aortic stenosis, aortic insufficiency, mitral stenosis and mitral insufficiency were significantly higher in NAFLD patients compared to the control group (1.2% vs. 0.22%, 1.32% vs. 0.32%, 0.66% vs. 0.27%, and 1.87% vs. 0.41%, respectively; P<0.001). In the multivariate logistic regression analysis, NAFLD was found to be independent risk factor for VHD (OR 2.39, 95% CI 2.17-2.78, P<0.001).

CONCLUSIONS

VHD was significantly seen more frequently in NAFLD patients compared to controls. Prospective studies are needed to validate our findings and to elucidate the pathogenesis of VHD in patients with NAFLD.

Cardiac abnormalities in patients with nonalcoholic fatty liver disease : Insights from auxiliary examinations

Nonalcoholic fatty liver disease (NAFLD) is one of the most common forms of chronic liver disease in developed countries and is associated with type 2 diabetes mellitus, obesity, hypertension, dyslipidemia, and metabolic syndrome. It is defined as steatosis in over 5% of hepatocytes. The disease spectrum of NAFLD ranges from simple fatty liver to nonalcoholic steatohepatitis, liver fibrosis, even hepatic cirrhosis. The disease affects various extra-hepatic systems such as the cardiovascular system and urinary system. Heart-related disease is identified as the leading cause of mortality in NAFLD patients rather than liver-related disease. In this review, we summarize the cardiac abnormalities (structural, functional, arrhythmic cardiac complications etc.) seen in NAFLD patients with the assistance of auxiliary examinations, such as electrocardiography, echocardiography, computed tomography, magnetic resonance imaging etc. In addition, the epidemiology of NAFLD and how NAFLD affects the myocardium are also discussed.

Atrial fibrillation is highly prevalent yet undertreated in patients with biopsy-proven nonalcoholic steatohepatitis

BACKGROUND & AIMS

Nonalcoholic steatohepatitis (NASH) is associated with increased cardiovascular disease. Atrial fibrillation is a prominent risk marker for underlying cardiovascular disease with a prevalence of 2% in patients <65 years old. Atrial fibrillation prevalence in NASH is unknown. We sought to assess the prevalence and impact of atrial fibrillation on healthcare utilization in NASH.

METHODS

Patients were identified from a tertiary care centre Electronic Database from 2002 to 2015. International Classification of Diseases 9 (ICD9) codes identified comorbidities and atrial fibrillation. Descriptive statistics were used to compare characteristics between patients with NASH with and without atrial fibrillation.

RESULTS

Of 9108 patients with ICD9 diagnosis of NASH, 215 (2.3%, mean age 57 years, 32% male) had biopsy-proven NASH. Atrial fibrillation prevalence was 4.6%. Patients with NASH and atrial fibrillation had a higher prevalence of heart failure (54.5% vs 8.8%, P < 0.001) and cerebrovascular (27.3% vs 2.0%, P < 0.001) or vascular disease (54.5% vs 13.2%, P = 0.002), compared to NASH without atrial fibrillation. All patients with NASH and atrial fibrillation had a CHA2DS2VASc score ≥2 indicating high stroke risk and need for anticoagulation. Eight of 10 patients were eligible for anticoagulation and 5 of 8 (62.5%) received appropriate therapy.

CONCLUSION

Atrial fibrillation prevalence is two-fold higher in patients with NASH compared to the general population. Patients with NASH have a high risk of stroke; however, many do not receive appropriate guideline-directed therapy. Future studies are needed to identify whether guideline-based management of atrial fibrillation in NASH reduces cardiovascular morbidity and mortality.

Gastrointestinal and liver diseases and atrial fibrillation: a review of the literature

Atrial fibrillation (AF) is the most common arrhythmia worldwide and is associated with significant morbidity and mortality. A number of risk factors have been associated with AF, though few studies have explored the association between gastrointestinal and liver diseases and AF. Additionally, AF and treatment for AF may predispose to gastrointestinal and liver diseases. We review the current literature on the bidirectional associations between gastrointestinal and liver diseases and AF. We highlight the gaps in knowledge and areas requiring future investigation.

Relation of Hepatic Fibrosis in Nonalcoholic Fatty Liver Disease to Left Ventricular Diastolic Function and Exercise Tolerance

The purpose of this study was to determine the relation between liver histology, exercise tolerance, and diastolic function in patients with nonalcoholic fatty liver disease (NAFLD). Myocardial remodeling and diastolic dysfunction have been associated with NAFLD. However, its physiological impact and relationship to the histological severity of NAFLD is not known. Cardiopulmonary exercise testing and stress echocardiography was performed in subjects with biopsy-confirmed NAFLD. Maximal aerobic exercise capacity (peak oxygen consumption [VO2]) was related to diastolic function (mitral annulus Doppler velocity e' and ratio of early diastolic filling pressure [E] to e' [E/e']) at rest and peak exercise. Autonomic dysfunction was determined from heart rate recovery after exercise. Independent predictors of cardiac function and exercise capacity were identified by multivariable regression. Thirty-six subjects (nonalcoholic fatty liver [NAFL  =  15], nonalcoholic steatohepatitis [NASH  =  21]) were enrolled. NASH was associated with impaired exercise capacity compared with NAFL (median peak VO2 17.0 [15.4, 18.9] vs 19.9 [17.4, 26.0], p  =  001); pVO2 declined with increasing fibrosis (F0  =  22.5, F1  =  19.9, F2  =  19.0, F3  =  16.6 ml·kg-1·min-1; p  =  0.01). Similarly, E/e' during exercise increased progressively with increasing fibrosis (F0  =  5.6, F1  =  6.5, F2  =  8.7, F3  =  9.8; P  =  0.02). Finally, heart rate recovery, a marker of autonomic function, was blunted in those with higher fibrosis stages (F0  =  25 [20, 30], F1  =  23 [17.5, 27.0], F2  =  17 [11.8, 21.5], F3  =  11 [8.5, 18.0] beats per minute; p <0.01). Fibrosis was an independent predictor of these functional outcomes. In conclusion, NASH is associated with impaired exercise capacity and diastolic dysfunction compared with NAFL. The severity of impairment is directly related to the severity of fibrosis stage in precirrhotic stages of NAFLD.

Magnetic Resonance Elastography of Liver: Current Update

The first clinical application of magnetic resonance elastography (MRE) was in the evaluation of chronic liver disease (CLD) for detection and staging of liver fibrosis. In the past 10 years, MRE has been incorporated seamlessly into a standard magnetic resonance imaging (MRI) liver protocol worldwide. Liver MRE is a robust technique for evaluation of liver stiffness and is currently the most accurate noninvasive imaging technology for evaluation of liver fibrosis. Newer MRE sequences including spin-echo MRE and 3 dimensional MRE have helped in reducing the technical limitations of clinical liver MRE that is performed with 2D gradient recalled echo (GRE) MRE. Advances in MRE technology have led to understanding of newer mechanical parameters such as dispersion, attenuation, and viscoelasticity that may be useful in evaluating pathological processes in CLD and may prove useful in their management.This review article will describe the changes in CLD that cause an increase in stiffness followed by principle and technique of liver MRE. In the later part of the review, we will briefly discuss the advances in liver MRE.

Insulin Resistance and Vulnerability to Cardiac Ischemia

Hepatic and myocardial ectopic lipid deposition has been associated with insulin resistance (IR) and cardiovascular risk. Lipid overload promotes increased hepatic oxidative capacity, oxidative stress, and impaired mitochondrial efficiency, driving the progression of nonalcoholic fatty liver disease (NAFLD). We hypothesized that higher lipid availability promotes ischemia-induced cardiac dysfunction and decreases myocardial mitochondrial efficiency. Mice with adipose tissue-specific overexpression of sterol element-binding protein 1c as model of lipid overload with combined NAFLD-IR and controls underwent reperfused acute myocardial infarcts (AMIs). Whereas indexes of left ventricle (LV) contraction were similar in both groups at baseline, NAFLD-IR showed severe myocardial dysfunction post-AMI, with prominent LV reshaping and increased end-diastolic and end-systolic volumes. Hearts of NAFLD-IR displayed hypertrophy, steatosis, and IR due to 18:1/18:1-diacylglycerol-mediated protein kinase Cε (PKCε) activation. Myocardial fatty acid-linked respiration and oxidative stress were increased, whereas mitochondrial efficiency was decreased. In humans, decreased myocardial mitochondrial efficiency of ventricle biopsies related to IR and troponin levels, a marker of impaired myocardial integrity. Taken together, increased lipid availability and IR favor susceptibility to ischemia-induced cardiac dysfunction. The diacylglycerol-PKCε pathway and reduced mitochondrial efficiency both caused by myocardial lipotoxicity may contribute to the impaired LV compensation of the noninfarcted region of the myocardium.

Is There an Association of Vascular Disease and Atherosclerosis in Children and Adolescents With Obesity and Non-alcoholic Fatty Liver Disease?

Carotid intima media thickness (cIMT) and brachial flow-mediated dilation (FMD) evaluated by ultrasound are non-invasive markers of atherosclerosis. Increased cIMT in adults has been correlated to early vascular damage. Several studies show similar correlations of elevated cIMT in children with obesity, hyperlipidemia, and metabolic syndrome. Additionally, several articles have correlated non-alcoholic fatty liver disease (NAFLD) with elevated cIMT, indicating early atherosclerosis. It is alarming that these vascular changes may be seen in children as young as 10 years of age. Children with NAFLD may also have an increased pulse wave velocity that correlates to increased arterial stiffness and increased left ventricular dimension, mass, and diastolic dysfunction. These articles are persuasive, indicating a correlation of Pediatric NAFLD and early vascular disease. However, study limitations include the use of elevated alanine aminotransferase (ALT) and echogenic changes on ultrasound that may have low accuracy to identify NAFLD. Ultrasound has low sensitivities and specificities for detection of NAFLD and therefore is not recommended for diagnosis. In comparison, studies that used liver biopsy or proton magnetic resonance spectroscopy to identify NAFLD did not find a correlation with elevated cIMT or reduction in FMD. Due to these conflicting findings, more studies looking at cIMT and FMD changes in children with NAFLD are needed with more accurate diagnostic methods for steatosis to identify if there truly is a correlation of increased liver steatosis to early atherosclerosis.

Chronic heart failure in patients with nonalcoholic fatty liver disease: prevalence, clinical features, and relevance

Objective This study was performed to assess the prevalence of nonalcoholic fatty liver (NAFL) in patients with symptomatic congestive heart failure (CHF) and compare the clinical features with those of patients without NAFL. Methods In total, 102 patients with CHF were divided into NAFL and non-NAFL groups according to their hepatic ultrasonography findings. All patients underwent transthoracic echocardiography and cardiac magnetic resonance examination. Follow-up was performed for major cardiovascular events (MACE) and readmission due to heart failure at 1, 3, 6, and 12 months after the index hospitalization. Results NAFL was detected in 37 of 102 patients (36.27%). Compared with the non-NAFL group, patients with NAFL were younger, had a higher body mass index and left ventricular (LV) mass index, and had more severe fibrosis. MACE and readmission occurred in 15 patients in the NAFL group and 29 patients in the non-NAFL group, without a significant difference. Linear regression analysis revealed that after adjusting for confounders, NAFL was independently associated with the LV fibrosis size and the ratio of the LV fibrosis size to the LV mass index. Conclusions NAFL is present in more than one-third of patients with CHF and is associated with the severity of LV fibrosis.

Assessment of Subclinical Myocardial Changes in Non-Alcoholic Fatty Liver Disease: A Case-Control Study Using Speckle Tracking Echocardiography

BACKGROUND

Considering the association between cardiac abnormalities and non-alcoholic fatty liver disease (NAFLD), the present study aimed to evaluate the relationship between biopsy-proven NAFLD and functional echocardiographic parameters, including left ventricular (LV) global longitudinal strain (GLS) in asymptomatic individuals.

METHODS

Thirty asymptomatic patients with liver biopsy-proven NAFLD and the same number with no evidence of fatty liver in ultrasonography were enrolled in the study as cases and controls, respectively. The measured echocardiographic parameters included LV ejection fraction (LVEF), LV end-systolic and end-diastolic dimensions (ESD, EDD), LV end-systolic and end-diastolic volumes (ESV, EDV), E/e' ratio (early-diastolic mitral inflow velocity/early-diastolic myocardial velocity), E/A ratio (early-diastolic mitral inflow velocity/late-diastolic mitral inflow velocity), and GLS. Data were analyzed using the SPSS statistical software (version 18.0) by performing the independent t test, Chi-square, and non-parametric Mann-Whitney U tests. P values <0.05 were considered statistically significant.

RESULTS

A significant difference in ESD (32.1±1.4 mm vs. 34±1.8 mm), EDD (41.9±1.7 mm vs. 45.2±3.1 mm), and E/e' ratio (8.4±0.8 vs. 7.4±1.2) was detected among individuals with NAFLD compared with those without NAFLD (P<0.001 for the first two parameters and P=0.002 for the last one). GLS was also significantly lower in NAFLD patients than in controls, but within normal levels (19.3%±2.0 vs. 21.2%±1.4, P<0.001).

CONCLUSION

The findings support the presence of subclinical cardiovascular structural and functional changes in patients affected by NAFLD. It also indicates that the use of GLS is more sensitive than LVEF for the detection of LV systolic dysfunction in NAFLD patients.

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.

Risk of cardiomyopathy and cardiac arrhythmias in patients with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a common, progressive liver disease that affects up to one-quarter of the adult population worldwide. The clinical and economic burden of NAFLD is mainly due to liver-related morbidity and mortality (nonalcoholic steatohepatitis, cirrhosis or hepatocellular carcinoma) and an increased risk of developing fatal and nonfatal cardiovascular disease, chronic kidney disease and certain types of extrahepatic cancers (for example, colorectal cancer and breast cancer). Additionally, there is now accumulating evidence that NAFLD adversely affects not only the coronary arteries (promoting accelerated coronary atherosclerosis) but also all other anatomical structures of the heart, conferring an increased risk of cardiomyopathy (mainly left ventricular diastolic dysfunction and hypertrophy, leading to the development of congestive heart failure), cardiac valvular calcification (mainly aortic-valve sclerosis), cardiac arrhythmias (mainly atrial fibrillation) and some cardiac conduction defects. This Review focuses on the association between NAFLD and non-ischaemia-related cardiac disease, discusses the putative pathophysiological mechanisms and briefly summarizes current treatment options for NAFLD that might also beneficially affect cardiac disease.

Association of non-alcoholic steatohepatitis with subclinical myocardial dysfunction in non-cirrhotic patients

BACKGROUND & AIMS

Non-alcoholic fatty liver disease (NAFLD) is associated with increased cardiovascular risk. Among categories of NAFLD, hepatic fibrosis is most likely to affect mortality. Myocardial function and its energy metabolism are tightly linked, which might be altered by an insulin resistant condition such as NAFLD. We investigated whether hepatic steatosis and fibrosis were associated with myocardial dysfunction relative to myocardial glucose uptake.

METHODS

A total of 308 patients (190 without NAFLD, 118 with NAFLD) were studied in a tertiary care hospital. Myocardial glucose uptake was evaluated at fasted state using [¹⁸F]-fluorodeoxyglucose-positron emission tomography (¹⁸FDG-PET). Hepatic steatosis and fibrosis were assessed by transient liver elastography (Fibroscan®) with controlled attenuation parameter, which quantifies hepatic fat and by surrogate indices (fatty liver index and NAFLD fibrosis score). Cardiac structure and function were examined by echocardiogram.

RESULTS

Compared to those without NAFLD, patients with NAFLD had alterations in cardiac remodeling, manifested by increased left ventricular mass index, left ventricular end-diastolic diameter, and left atrial volume index (all p <0.05). Hepatic steatosis was significantly associated with left ventricular filling pressure (E/e' ratio), which reflects diastolic dysfunction (p for trend <0.05). Those without NAFLD were more likely to have higher myocardial glucose uptake compared to those with NAFLD. Significant hepatic fibrosis was also correlated with diastolic dysfunction and impaired myocardial glucose uptake. Using multivariable linear regression, E/e' ratio was independently associated with hepatic fibrosis (standardized β = 0.12 to 0.27; all p <0.05). Association between hepatic steatosis and E/e' ratio was also significant (standardized β = 0.10 to 0.15; all p <0.05 excluding the model adjusted for adiposity).

CONCLUSIONS

Hepatic steatosis and fibrosis are significantly associated with diastolic heart dysfunction. This association is linked with myocardial glucose uptake evaluated by ¹⁸FDG-PET.

LAY SUMMARY

Non-alcoholic fatty liver disease is associated with an increased risk of cardiovascular disease. More severe forms of non-alcoholic fatty liver disease, where hepatic fibrosis occurs, are linked to increased mortality. In this study, we have shown that hepatic steatosis and fibrosis are associated with subclinical myocardial dysfunction. This association is linked to altered myocardial glucose uptake.

The Role of Nonalcoholic Fatty Liver Disease on Cardiovascular Manifestations and Outcomes

Cardiovascular disease has been postulated as the leading cause of mortality among patients with nonalcoholic fatty liver disease (NAFLD), rather than from sequalae of liver disease specifically. While there is ample evidence validating the association between NAFLD and increased cardiovascular comorbidities, events, and mortality, current data presents a challenge in attributing this effect solely due to NAFLD given the rampant presence of insulin resistance and type 2 diabetes mellitus (T2DM). Endpoints of increased cardiovascular risk remains tightly linked to the concomitant presence of insulin resistance and T2DM. Prospective studies accentuating early detection of NAFLD are imperative to institute early intervention and prevent future cardiovascular events.

The influence of NAFLD on the risk of atherosclerosis and cardiovascular diseases

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in developed countries and is associated with obesity, dyslipidaemia, diabetes, and metabolic syndrome. Atherosclerosis and cardiovascular diseases are also highly prevalent in this group of patients, due to the presence of shared risk factors. The incidences of coronary artery calcification, hypertension, aortic valve sclerosis, diastolic dysfunction, atherosclerotic plaques, and increased carotid intima-media thickness were more common in patients with NAFLD than in those without. The present paper reviews the medical literature concerning the association between NAFLD and cardiovascular events.

Non-Alcoholic Fatty Liver Disease: The Emerging Burden in Cardiometabolic and Renal Diseases

As the number of individuals with non-alcoholic fatty liver disease (NAFLD) has increased, the influence of NAFLD on other metabolic diseases has been highlighted. Accumulating epidemiologic evidence indicates that NAFLD not only affects the liver but also increases the risk of extra-hepatic diseases such as type 2 diabetes mellitus, metabolic syndrome, dyslipidemia, hypertension, cardiovascular or cerebrovascular diseases, and chronic kidney disease. Non-alcoholic steatohepatitis, an advanced type of NAFLD, can aggravate these inter-organ relationships and lead to poorer outcomes. NAFLD induces insulin resistance and exacerbates systemic chronic inflammation and oxidative stress, which leads to organ dysfunction in extra-hepatic tissues. Although more research is needed to identify the pathophysiological mechanisms and causal relationship between NAFLD and cardiometabolic and renal diseases, screening for heart, brain, and kidney diseases, risk assessment for diabetes, and a multidisciplinary approach for managing these patients should be highly encouraged.

A High-Fat and High-Cholesterol Diet Induces Cardiac Fibrosis, Vascular Endothelial, and Left Ventricular Diastolic Dysfunction in SHRSP5/Dmcr Rats

AIM

Non-alcoholic steatohepatitis (NASH) increases cardiovascular risk regardless of risk factors in metabolic syndrome. However, the intermediary factors between NASH and vascular disease are still unknown because a suitable animal model has never been established. The stroke-prone (SP) spontaneously hypertensive rat, SHRSP5/Dmcr, simultaneously develops hypertension, acute arterial lipid deposits in mesenteric arteries, and NASH when feed with a high-fat and high-cholesterol (HFC) diet. We investigated whether SHRSP5/Dmcr affected with NASH aggravates the cardiac or vascular dysfunction.

METHOD

Wister Kyoto and SHRSP5/Dmcr rats were divided into 4 groups of 5 rats each, and fed with a SP or HFC diet. After 8 weeks of HFC or SP diet feeding, glucose and insulin resistance, echocardiography, blood biochemistry, histopathological staining, and endothelial function in aorta were evaluated.

RESULTS

We demonstrate that SHRSP5/Dmcr rats fed with a HFC diet presented with cardiac and vascular dysfunction caused by cardiac fibrosis, endothelial dysfunction, and left ventricular diastolic dysfunction, in association with NASH and hypertension. These cardiac and vascular dysfunctions were aggravated and not associated with the presence of hypertension, glucose metabolism disorder, and/or obesity.

CONCLUSIONS

SHRSP5/Dmcr rats may be a suitable animal model for elucidating the organ interaction between NASH and cardiac or vascular dysfunction.

Nonalcoholic fatty liver disease as a predictor of atrial fibrillation: a systematic review and meta-analysis

INTRODUCTION

Numerous epidemiologic studies have investigated the link between nonalcoholic fatty liver disease (NAFLD) and long-term atrial fibrillation (AF) risk, but the results are surprisingly conflicting.

AIM

Therefore, we systematically reviewed all published studies assessing the risk of AF in patients with NAFLD and conducted a meta-analysis.

MATERIAL AND METHODS

We performed a literature search using PubMed, EMBASE and Cochrane Library databases in February 2017 with no restrictions. Two cohort studies and two cross-sectional studies were identified, involving a total of 5150 subjects (NAFLD: 1655; controls: 3495) in this meta-analysis. Data from selected studies were extracted and a meta-analysis was performed using a random effects model.

RESULTS

Nonalcoholic fatty liver disease patients had a significantly higher risk of AF compared to controls (relative risk (RR): 2.61; 95% confidence interval (CI): 1.34-5.06, p = 0.00; I² = 52.5%, p = 0.097). In a further analysis stratified by presence of type 2 diabetes, the increased risk was present predominantly in patients with type 2 diabetes (RR = 5.10; 95% CI: 2.43-10.7, p < 0.001; I² = 0, p = 0.958). However, subjects without type 2 diabetes were at slightly increased risk of AF but the relative risk did not reach statistical significance (RR = 1.68; 95% CI: 0.99-2.82, p = 0.05; I² = 0, p = 0.461).

CONCLUSIONS

Our meta-analysis suggested that ultrasound-diagnosed NAFLD patients have a significantly higher risk for AF after adjustment for numerous important clinical risk factors for AF. These results need to be confirmed in large prospective studies.

Is hepatic steatosis associated with left ventricular mass index increase in the general population?

AIM

To investigate the association between hepatic steatosis and change in left ventricular mass index (LVMI) over five years, and examine whether systolic and diastolic blood pressures are mediators of the association between hepatic steatosis and LVMI using a general population sample.

METHODS

We analyzed data from the Study of Health in Pomerania. The study population comprised 1298 individuals aged 45 to 81 years. Hepatic steatosis was defined as the presence of a hyperechogenic pattern of the liver together with elevated serum alanine transferase levels. Left ventricular mass was determined echocardiographically and indexed to height^2.7. Path analyses were conducted to differentiate direct and indirect paths from hepatic steatosis to LVMI encompassing systolic and diastolic blood pressure as potential mediating variables.

RESULTS

Hepatic steatosis was a significant predictor for all measured echocardiographic characteristics at baseline. Path analyses revealed that the association of hepatic steatosis with LVMI change after five years was negligibly small (β = -0.12, s.e. = 0.21, P = 0.55). Systolic blood pressure at baseline was inversely associated with LVMI change (β = -0.09, s.e. = 0.03, P < 0.01), while no association between diastolic blood pressure at baseline and LVMI change was evident (β = 0.03, s.e. = 0.05, P = 0.56). The effect of the indirect path from hepatic steatosis to LVMI via systolic baseline blood pressure was small (β = -0.20, s.e. = 0.10, P = 0.07). No indirect effect was observed for the path via diastolic baseline blood pressure (β = 0.03, s.e. = 0.06, P = 0.60). Similar associations were observed in the subgroup of individuals not receiving beta-blockers, calcium channel blockers, or drugs acting on the renin-angiotensin system.

CONCLUSION

Baseline associations between hepatic steatosis and LVMI do not extend to associations with LVMI change after five years. More studies are needed to study the longitudinal effects of hepatic steatosis on LVMI.

Non-alcoholic fatty liver disease and its relationship with cardiovascular disease and other extrahepatic diseases

Key physiological functions of the liver, including glucose and lipid metabolism, become disturbed in the setting of non-alcoholic fatty liver disease (NAFLD) and may be associated with a systemic inflammatory 'milieu' initiated in part by liver-secreted cytokines and molecules. Consequently, the pathophysiological effects of NAFLD extend beyond the liver with a large body of clinical evidence demonstrating NAFLD to be independently associated with both prevalent and incident cardiovascular disease (CVD), chronic kidney disease (CKD) and type 2 diabetes mellitus (T2DM). The magnitude of risk of developing these extrahepatic diseases parallels the underlying severity of NAFLD, such that patients with non-alcoholic steatohepatitis (NASH) appear to be at greater risk of incident CVD, CKD and T2DM than those with simple steatosis. Other modifiers of risk may include genetic variants (eg, patatin-like phospholipase domain-containing 3 and trans-membrane 6 superfamily member 2 polymorphisms), visceral adipose tissue accumulation, dietary intake and the gut microbiome. Emerging data also suggest that NAFLD may be a risk factor for colonic neoplasia and reduced bone mineral density, especially among men. Importantly, improvement/resolution of NAFLD is associated with a reduced incidence of T2DM and improved kidney function, adding weight to causality and suggesting liver focused treatments may reduce risk of extrahepatic complications. Awareness of these associations is important for the clinicians such that CVD risk factor management, screening for T2DM and CKD are part of the routine management of patients with NAFLD.

Relations of Liver Fat With Prevalent and Incident Atrial Fibrillation in the Framingham Heart Study

Background

Obesity is an important risk factor for nonalcoholic fatty liver disease and atrial fibrillation (AF). Less is known about the relations between nonalcoholic fatty liver disease and AF. We sought to evaluate the association between fatty liver and prevalent and incident AF in the community.

Methods and Results

We examined Framingham Heart Study participants who underwent a study‐directed computed tomography scan, had hepatic steatosis (HS) evaluated, and did not report heavy alcohol use between 2002 and 2005. We evaluated cross‐sectional associations between liver fat and prevalent AF with logistic regression models. We assessed the relations between liver fat and incident AF during 12‐year follow‐up with Cox proportional hazards models. Of 2122 participants (53% women; mean age, 59.0±9.6 years), 20% had HS. AF prevalence (n=62) among individuals with HS was 4% compared to 3% among those without HS. There was no significant association between HS (measured as continuous or dichotomous variables) and prevalent AF in age‐ and sex‐adjusted or multivariable‐adjusted models. Incidence of AF (n=153) among participants with and without HS was 8.7 cases and 7.8 cases per 1000 person‐years, respectively. In age‐ and sex‐adjusted and multivariable‐adjusted models, there were no significant associations between continuous or dichotomous measures of HS and incident AF.

Conclusions

In our community‐based, longitudinal cohort study, liver fat by computed tomography scan was not significantly associated with increased prevalence or incidence of AF over 12 years of follow‐up.

Non-Alcoholic Fatty Liver Disease Association with Cardiac Arrhythmias

Non-alcoholic fatty liver disease (NAFLD) has become a public health burden all over the world. A significant percentage of the patients with NAFLD have a co-existing metabolic syndrome that is a risk factor for cardiovascular disease. Clinical as well as epidemiological research shows that NAFLD is not simply related to liver-related morbidity and mortality but is also associated with an elevated risk of coronary heart disease (CHD), irregularities of cardiac function as well as cardiac structure, valvular heart disease, and arrhythmias. Animal studies suggest that NAFLD by itself exacerbates systemic/hepatic insulin resistance, leads to atherogenic dyslipidemia and generates a number of pro-inflammatory, pro-coagulant and profibrogenic mediators which play an essential role in the pathophysiology of cardiac abnormalities including arrhythmias. Hence, it is suggested that the patients with NAFLD may derive benefit from intensive monitoring and treatment methods to reduce the risk of CHD along with other cardiac/arrhythmic complications. The intent of this clinical review is to sum up the quickly increasing body of evidence that provides support for a robust relationship between NAFLD and cardiac arrhythmias and to present the putative biological mechanisms underlying this correlation.

Diagnostic accuracy of serum alanine aminotransferase as biomarker for nonalcoholic fatty liver disease and insulin resistance in healthy subjects, using 3T MR spectroscopy

Recognition of the close relationship of nonalcoholic fatty liver disease (NAFLD) with diabetes mellitus 2, obesity, metabolic syndrome, and cardiovascular disease has stimulated growing interest in NAFLD as a public health problem. Serum alanine aminotransferase (ALT) has been proposed as a marker of NAFLD, but levels are within the range currently considered "normal" in a large proportion of NAFLD subjects.The aim of the study was to determine the diagnostic accuracy of serum ALT for identifying individuals with NAFLD, using 3-Tesla (T) magnetic resonance spectroscopy (H-MRS).A cross-sectional study was conducted in 129 healthy subjects. Liver triglyceride content was quantified by H-MRS. NAFLD was defined as liver triglyceride content greater than 5.56%.Liver triglyceride content was >5.56% in 79 participants (NAFLD) and lower in the remaining 50 (normal). Serum ALT levels correlated positively with liver triglyceride content (r = 0.58, P < .001), Homeostatic Model Assessment for Insulin Resistance (r = 0.32, P < .01), and fasting insulin (r = 0.31, P < .01), and inversely correlated with adiponectin (r = 0.35, P < .01) and high-density lipoprotein cholesterol (r = 0.32, P < .01). Regression analysis showed that serum ALT was the best predictor of NAFLD (P < .01). Optimal serum ALT cut-off to predict NAFLD was 23 IU/L (area under receiver-operating characteristic curve: 0.93; sensitivity: 0.94; specificity: 0.72).This study shows that serum ALT is a sensitive and accurate biomarker of NAFLD if the "normal" ALT value is revised and established at a lower level. An ALT threshold of 23 IU/L identified 94% of individuals with NAFLD in the present series, using 3-T H-MRS for liver triglyceride quantification.