Atrial Fibrillation and Heart Failure With Preserved Ejection Fraction in Patients With Nonalcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease and heart failure: A comprehensive bioinformatics and Mendelian randomization analysis

AIMS

Heart failure (HF) and non-alcoholic fatty liver disease (NAFLD) are significant global health issues with a complex interrelationship. This study investigates their shared biomarkers and causal relationships using bioinformatics and Mendelian randomization (MR) approaches.

METHODS

We analysed NAFLD and HF datasets from the Gene Expression Omnibus (GEO). The GSE126848 dataset included 57 liver biopsy samples [14 healthy individuals, 12 obese subjects, 15 NAFL patients and 16 non-alcoholic steatohepatitis (NASH) patients]. The GSE24807 dataset comprised 12 NASH samples and 5 healthy controls. The GSE57338 dataset included 313 cardiac muscle samples [177 HF patients (95 ischaemic heart disease patients and 82 idiopathic dilated cardiomyopathy patients) and 136 healthy controls]. The GSE84796 dataset consisted of 10 end-stage HF patients and 7 healthy hearts procured from organ donors. We identified differentially expressed genes (DEGs) and constructed a protein-protein interaction (PPI) network. Functional pathways were elucidated through enrichment analyses using Gene Ontology (GO), the Kyoto Encyclopedia of Genes and Genomes (KEGG) and GeneMANIA annotation. Single nucleotide polymorphism (SNP) data for HF and NAFLD were sourced from genome-wide association studies (GWAS). The HF dataset included 486 160 samples (14 262 experimental and 471 898 control), and the NAFLD dataset comprised 377 988 samples (4761 experimental and 373 227 control). MR analysis investigates the causal interrelations.

RESULTS

Our analysis revealed 4032 DEGs from GSE126848 and 286 DEGs from GSE57338. The top 10 hub genes (CD163, VSIG4, CXCL10, FCER1G, FPR1, C1QB, CCR1, C1orf162, MRC1 and CD38) were significantly enriched in immune response, calcium ion concentration regulation and positive regulation of monocyte chemotaxis. CIBERSORT analysis indicated associations between these hub genes and natural killer (NK) cells and macrophages. Transcription factor (TF) target prediction for CD38, CXCL10 and CCR1 highlighted related TFs. A two-sample MR analysis confirmed a bidirectional causal relationship between NAFLD and HF. The main method [inverse variance weighted (IVW)] demonstrated a significant positive causal relationship between NAFLD and HF [P = 0.037; odds ratio (OR) = 1.024; 95% confidence interval (CI): 1.001 to 1.048]. Similarly, HF was associated with an increase in the risk of NAFLD (P < 0.001; OR = 1.117; 95% CI: 1.053 to 1.185).

CONCLUSIONS

Our findings reveal novel molecular signatures common to NAFLD and HF and confirm their bidirectional causality, highlighting the potential for targeted therapeutic interventions and prompting further investigation into their intricate relationship.

Rapid Uptitration of Guideline-Directed Medical Therapies in Acute Heart Failure With and Without Atrial Fibrillation

BACKGROUND

Rapid uptitration of guideline-directed medical therapy (GDMT) before and after discharge in hospitalized heart failure (HF) patients is feasible, is safe, and improves outcomes; whether this is also true in patients with coexistent atrial fibrillation/flutter (AF/AFL) is not known.

OBJECTIVES

This study sought to investigate whether rapid GDMT uptitration before and after discharge for HF is feasible, safe and beneficial in patients with and without AF/AFL.

METHODS

In this secondary analysis of the STRONG-HF (Safety, Tolerability, and Efficacy of Rapid Optimization, Helped by NT-proBNP Testing, of Heart Failure Therapies) trial, GDMT uptitration and patient outcomes were analyzed by AF/AFL status and type (permanent, persistent, paroxysmal).

RESULTS

Among 1,078 patients enrolled in STRONG-HF, 496 (46%) had a history of AF, including 238 assigned to high-intensity care (HIC) and 258 to usual care (UC), and 581 did not have a history of AF/AFL, including 304 assigned to HIC and 277 to UC. By day 90, the average percent optimal dose of neurohormonal inhibitors achieved in the HIC arm was similar in patients with and without AF/AFL, reaching approximately 80% of the optimal dose (average absolute difference between AF/AFL and non-AF/AFL groups: -0.81%; 95% CI: -3.51 to 1.89). All-cause death or HF readmission by day 180 occurred less frequently in the HIC than the UC arm, both in patients with and without AF (adjusted HR: 0.75 [95% CI: 0.48-1.19] in AF vs adjusted HR: 0.50 [95% CI: 0.31-0.79] in non-AF/AFL patients; P for interaction = 0.2107). Adverse event rates were similar in patients with and without AF/AFL. AF/AFL type did not affect either uptitration or patient outcomes.

CONCLUSIONS

Nearly half of acute HF patients have AF/AFL history. Rapid GDMT uptitration before and early after discharge is feasible, is safe, and may improve outcomes regardless of AF presence or type. (Safety, Tolerability, and Efficacy of Rapid Optimization, Helped by NT-proBNP Testing, of Heart Failure Therapies [STRONG-HF]; NCT03412201).

Liver Fibrosis Assessed Via Noninvasive Tests Is Associated With Incident Heart Failure in a General Population Cohort

BACKGROUND & AIMS

The aim of this study was to determine whether liver fibrosis is associated with heart failure in a general population cohort, and if genetic polymorphisms (PNPLA3 rs738409; TM6SF2 rs58542926), linked to increased risk of liver fibrosis and decreased risk of coronary artery disease, modify this association.

METHODS

Using UK Biobank data, we prospectively examined the relationship between noninvasive fibrosis markers (nonalcoholic fatty liver disease [NAFLD] fibrosis score [NFS], Fibrosis-4 [FIB-4] and aspartate transaminase [AST] to platelet ratio index [APRI]) and incident hospitalization/death from heart failure (n = 413,860). Cox-regression estimated hazard ratios (HRs) for incident heart failure. Effects of PNPLA3 and TM6SF2 on the association between liver fibrosis and heart failure were estimated by stratifying for genotype and testing for an interaction between genotype and liver fibrosis using a likelihood ratio test.

RESULTS

A total of 12,527 incident cases of heart failure occurred over a median of 10.7 years. Liver fibrosis was associated with an increased risk of hospitalization or death from heart failure (multivariable adjusted high-risk NFS score HR, 1.59; 95% confidence interval [CI],1.47-1.76; P < .0001; FIB-4 HR, 1.69; 95% CI, 1.55-1.84; P < .0001; APRI HR, 1.85; 95% CI, 1.56-2.19; P < .0001; combined fibrosis scores HR, 1.90; 95% CI, 1.44-2.49; P < .0001). These associations persisted for people with metabolic dysfunction-associated steatotic liver disease (MASLD), MASLD with alcohol consumption (Met-ALD), and harmful alcohol consumption. PNPLA3 rs738409 GG and TM6SF2 rs58542926 TT did not attenuate the positive association between fibrosis markers and heart failure. For PNPLA3, a statistically significant interaction was found between PNPLA3 rs738409, FIB-4, APRI score, and heart failure.

CONCLUSION

In the general population, serum markers of liver fibrosis are associated with increased hospitalization/death from heart failure. Genetic polymorphisms associated with liver fibrosis were not positively associated with elevated heart failure risk.

High-Sensitivity C-Reactive Protein Is Associated With Heart Failure Hospitalization in Patients With Metabolic Dysfunction-Associated Fatty Liver Disease and Normal Left Ventricular Ejection Fraction Undergoing Coronary Angiography

BACKGROUND

Systemic chronic inflammation plays a role in the pathophysiology of both heart failure with preserved ejection fraction (HFpEF) and metabolic dysfunction-associated fatty liver disease. This study aimed to investigate whether serum hs-CRP (high-sensitivity C-reactive protein) levels were associated with the future risk of heart failure (HF) hospitalization in patients with metabolic dysfunction-associated fatty liver disease and a normal left ventricular ejection fraction.

METHODS AND RESULTS

The study enrolled consecutive individuals with metabolic dysfunction-associated fatty liver disease and normal left ventricular ejection fraction who underwent coronary angiography for suspected coronary heart disease. The study population was subdivided into non-HF, pre-HFpEF, and HFpEF groups at baseline. The study outcome was time to the first hospitalization for HF. In 10 019 middle-aged individuals (mean age, 63.3±10.6 years; 38.5% women), the prevalence rates of HFpEF and pre-HFpEF were 34.2% and 34.5%, with a median serum hs-CRP level of 4.5 mg/L (interquartile range, 1.9-10 mg/L) and 5.0 mg/L (interquartile range, 2.1-10.1 mg/L), respectively. Serum hs-CRP levels were significantly higher in the pre-HFpEF and HFpEF groups than in the non-HF group. HF hospitalizations occurred in 1942 (19.4%) patients over a median of 3.2 years, with rates of 3.7% in non-HF, 20.8% in pre-HFpEF, and 32.1% in HFpEF, respectively. Cox regression analyses showed that patients in the highest hs-CRP quartile had a ≈4.5-fold increased risk of being hospitalized for HF compared with those in the lowest hs-CRP quartile (adjusted-hazard ratio, 4.42 [95% CI, 3.72-5.25]).

CONCLUSIONS

There was a high prevalence of baseline pre-HFpEF and HFpEF in patients with metabolic dysfunction-associated fatty liver disease and suspected coronary heart disease. There was an increased risk of HF hospitalization in those with elevated hs-CRP levels.

The liver-heart axis in patients with severe obesity: The association between liver fibrosis and chronic myocardial injury may be explained by shared risk factors of cardiovascular disease

BACKGROUND

Severe obesity is associated with increased risk of non-alcoholic fatty liver disease and cardiovascular disease. We hypothesized that liver fibrosis as quantified by the Enhanced Liver Fibrosis (ELF) test would be predictive of myocardial injury and fibrosis, expressed by higher concentrations of cardiac troponin T and I measured by high-sensitivity assays (hs-cTnT and hs-cTnI, respectively).

MATERIAL AND METHODS

We performed cross-sectional analyses of baseline data from 136 patients (mean age 45 years, 38 % male) with severe obesity participating in the non-randomized clinical trial Prevention of Coronary Heart Disease in Morbidly Obese Patients (ClinicalTrials.gov NCT00626964). Associations between ELF scores, hs-cTnT, and hs-cTnI concentrations were assessed using linear regression analysis.

RESULTS

ELF scores were associated with hs-cTnT in the unadjusted model (B 0.381, 95 % Confidence Interval [CI] 0.247, 0.514), but the association was attenuated upon adjustment for potential confounders (B -0.031, 95 % CI -0.155, 0.093). Similarly, for hs-cTnI, an observed association with ELF scores in the unadjusted model was attenuated upon adjustment for potential confounders ((B 0.432, 95 % CI 0.179, 0.685) and (B 0.069, 95 % CI -0.230, 0.367), respectively). Age, sex, hypertension, and estimated glomerular filtration rate were amongst the shared predictors of ELF score, hs-cTnT, and hs-cTnI that provided the univariable models with the highest R-squared and lowest Akaike Information Criterion values.

CONCLUSIONS

Contrary to our hypothesis, ELF score did not predict myocardial injury and fibrosis, but we rather demonstrated an association between liver fibrosis and myocardial injury and fibrosis may be explained by shared risk factors of cardiovascular disease.

A comparison between patients with various etiologies of cirrhosis and examination of cardiac risk factors limiting survival to liver transplantation

BACKGROUND & AIMS

Objectives of this retrospective cohort study were to assess differences in patient survival between etiologies of cirrhosis while on the waitlist for liver transplantation (LT), and to identify cardiac risk factors that predict survival failure while on the waitlist for LT.

METHODS

This single-center retrospective cohort design included adult patients who were listed for LT at a tertiary academic hospital with a high-volume liver transplant center.

RESULTS

Of the 653 patients listed for LT during the study period, 507 (77.6%) survived to transplant and 146 (22.4%) died or clinically deteriorated prior to transplant. Cumulative incidence of death or clinical deterioration did not differ statistically between patient groups (log rank p = .11). In multivariate analysis, compared to patients with NAFLD, there were no significant differences between patients with alcoholic cirrhosis (HR .95, 95%, CI, .62-1.45), cryptogenic cirrhosis (HR 1.31, 95%, CI, .77-2.23), or hepatitis C cirrhosis (HR 1.12, 95%, CI, .66-1.90). However, higher MELD scores (HR = 1.52, 95% CI, 1.12-1.19), severe coronary artery disease (HR = 2.09 95% CI, 1.23-3.55), and tricuspid regurgitation (HR = 2.62, 95% CI, 1.31-5.26) were independently associated with increased risk for survival failure to LT.

CONCLUSIONS

The presence of severe coronary artery disease and tricuspid regurgitation at the time of listing for transplant are associated with survival failure while on the LT waitlist across etiologies of liver disease. Diagnostic assessment of coronary and valvular disease should be considered in all patients undergoing evaluation for LT, such as cardiac catheterization and/or stress echocardiogram.

Epigenetics in Heart Failure: Role of DNA Methylation in Potential Pathways Leading to Heart Failure with Preserved Ejection Fraction

This review will focus on epigenetic modifications utilizing the DNA methylation mechanism, which is potentially involved in the pathogenesis of heart failure with preserved ejection fraction (HFpEF). The putative pathways of HFpEF will be discussed, specifically myocardial fibrosis, myocardial inflammation, sarcoplasmic reticulum Ca2+-ATPase, oxidative-nitrosative stress, mitochondrial and metabolic defects, as well as obesity. The relationship of HFpEF to aging and atrial fibrillation will be examined from the perspective of DNA methylation.

The impact of non-alcoholic fatty liver disease and liver fibrosis on adverse clinical outcomes and mortality in patients with chronic kidney disease: a prospective cohort study using the UK Biobank

BACKGROUND

Chronic kidney disease (CKD) and non-alcoholic fatty liver disease (NAFLD) frequently co-exist. We assess the impact of having NAFLD on adverse clinical outcomes and all-cause mortality for people with CKD.

METHODS

A total of 18,073 UK Biobank participants identified to have CKD (eGFR < 60 ml/min/1.73 m² or albuminuria > 3 mg/mmol) were prospectively followed up by electronic linkage to hospital and death records. Cox-regression estimated the hazard ratios (HR) associated with having NAFLD (elevated hepatic steatosis index or ICD-code) and NAFLD fibrosis (elevated fibrosis-4 (FIB-4) score or NAFLD fibrosis score (NFS)) on cardiovascular events (CVE), progression to end-stage renal disease (ESRD) and all-cause mortality.

RESULTS

56.2% of individuals with CKD had NAFLD at baseline, and 3.0% and 7.7% had NAFLD fibrosis according to a FIB-4 > 2.67 and NFS ≥ 0.676, respectively. The median follow-up was 13 years. In univariate analysis, NAFLD was associated with an increased risk of CVE (HR 1.49 [1.38-1.60]), all-cause mortality (HR 1.22 [1.14-1.31]) and ESRD (HR 1.26 [1.02-1.54]). Following multivariable adjustment, NAFLD remained an independent risk factor for CVE overall (HR 1.20 [1.11-1.30], p < 0.0001), but not ACM or ESRD. In univariate analysis, elevated NFS and FIB-4 scores were associated with increased risk of CVE (HR 2.42 [2.09-2.80] and 1.64 [1.30-2.08]) and all-cause mortality (HR 2.82 [2.48-3.21] and 1.82 [1.47-2.24]); the NFS score was also associated with ESRD (HR 5.15 [3.52-7.52]). Following full adjustment, the NFS remained associated with an increased incidence of CVE (HR 1.19 [1.01-1.40]) and all-cause mortality (HR 1.31 [1.13-1.52]).

CONCLUSIONS

In people with CKD, NAFLD is associated with an increased risk of CVE, and the NAFLD fibrosis score is associated with an elevated risk of CVE and worse survival.

Comparison of liver fibrosis scores for predicting mortality and morbidity in heart failure with preserved ejection fraction

AIMS

Liver fibrosis scores (LFSs) are non-invasive and effective tools for estimating cardiovascular risks. To better understand the advantages and limitations of currently available LFSs, we determined to compare the predictive values of LFSs in heart failure with preserved ejection fraction (HFpEF) for primary composite outcome, atrial fibrillation (AF), and other clinical outcomes.

METHODS AND RESULTS

This was a secondary analysis of the TOPCAT trial, and 3212 HFpEF patients were enrolled. Five LFSs, namely, non-alcoholic fatty liver disease fibrosis score (NFS), fibrosis-4 score (FIB-4), BARD, aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ratio, and Health Utilities Index (HUI) scores were adopted. Cox proportional hazard model and competing risk regression model were performed to assess the associations between LFSs and outcomes. The discriminatory power of each LFS was evaluated by calculating the area under the curves (AUCs). During a median follow-up of 3.3 years, a 1-point increase in the NFS [hazard ratio (HR) 1.10; 95% confidence interval (CI) 1.04-1.17], BARD (HR 1.19; 95% CI 1.10-1.30), and HUI (HR 1.44; 95% CI 1.09-1.89) scores was associated with an increased risk of primary outcome. Patients with high levels of NFS (HR 1.63; 95% CI 1.26-2.13), BARD (HR 1.64; 95% CI 1.25-2.15), AST/ALT ratio (HR 1.30; 95% CI 1.05-1.60), and HUI (HR 1.25; 95% CI 1.02-1.53) were at an increased risk of primary outcome. Subjects who developed AF were more likely to have high NFS (HR 2.21; 95% CI 1.13-4.32). High levels of NFS and HUI scores were a significant predictor of any hospitalization and hospitalization for heart failure. The AUCs for the NFS in predicting primary outcome (0.672; 95% CI 0.642-0.702) and incident of AF (0.678; 95% CI 0.622-0.734) were higher than other LFSs.

CONCLUSIONS

In light of these findings, NFS appears to have superior predictive and prognostic utility compared with AST/ALT ratio, FIB-4, BARD, and HUI scores.

CLINICAL TRIAL REGISTRATION

(https://clinicaltrials.gov). Unique identifier: NCT00094302.

Effects of treatment of non-alcoholic fatty liver disease on heart failure with preserved ejection fraction

In the past few decades, non-alcoholic fatty liver disease (NAFLD) and heart failure with preserved ejection fraction (HFpEF) have become the most common chronic liver disease and the main form of heart failure (HF), respectively. NAFLD is closely associated with HFpEF by sharing common risk factors and/or by boosting systemic inflammation, releasing other secretory factors, and having an expansion of epicardial adipose tissue (EAT). Therefore, the treatments of NAFLD may also affect the development and prognosis of HFpEF. However, no specific drugs for NAFLD have been approved by the Food and Drug Administration (FDA) and some non-specific treatments for NAFLD are applied in the clinic. Currently, the treatments of NAFLD can be divided into non-pharmacological and pharmacological treatments. Non-pharmacological treatments mainly include dietary intervention, weight loss by exercise, caloric restriction, and bariatric surgery. Pharmacological treatments mainly include administering statins, thiazolidinediones, glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter 2 inhibitors, and metformin. This review will mainly focus on analyzing how these treatments may affect the development and prognosis of HFpEF.

Non-alcoholic fatty liver disease is associated with a worse prognosis in patients with heart failure: A pool analysis

Background and aims

Non-alcoholic fatty liver disease (NAFLD) is associated with a higher risk of heart failure (HF) than those without NAFLD. However, the prognostic impact of NAFLD in HF is still controversial. This meta-analysis aimed to explore the association between NAFLD and the risk of adverse outcomes in patients with HF.

Methods

We searched multiple electronic databases (Embase, PubMed, and Google Scholar) for potentially related studies up to June 30, 2022. Cohort studies reported multivariable adjusted relative risks and 95% confidence intervals (CIs) of adverse outcomes in HF patients with NAFLD comparing those without NAFLD were included for analysis.

Results

A total of six studies involving 12,374 patients with HF were included for analysis, with a median follow-up duration of 2.5 years. The pooled analysis showed that HF patients with NAFLD were associated with a significantly increased risk of major composite adverse outcomes (HR 1.61, 95% CI 1.25-2.07), all-cause mortality (HR 1.66, 95% CI 1.39-1.98), and HF hospitalization or re-hospitalization (HR 1.71, 95% CI 1.03-2.86).

Conclusion

NAFLD is associated with a worse prognosis in patients with HF. Effective screening and treatment strategies are needed to improve the prognosis in HF patients with NAFLD.

Comprehensive Review of Cardiovascular Disease Risk in Nonalcoholic Fatty Liver Disease

Nonalcoholic Fatty Liver Disease (NAFLD) is a growing global phenomenon, and its damaging effects in terms of cardiovascular disease (CVD) risk are becoming more apparent. NAFLD is estimated to affect around one quarter of the world population and is often comorbid with other metabolic disorders including diabetes mellitus, hypertension, coronary artery disease, and metabolic syndrome. In this review, we examine the current evidence describing the many ways that NAFLD itself increases CVD risk. We also discuss the emerging and complex biochemical relationship between NAFLD and its common comorbid conditions, and how they coalesce to increase CVD risk. With NAFLD's rising prevalence and deleterious effects on the cardiovascular system, a complete understanding of the disease must be undertaken, as well as effective strategies to prevent and treat its common comorbid conditions.

Liver-heart cross-talk mediated by coagulation factor XI protects against heart failure

Tissue-tissue communication by endocrine factors is a vital mechanism for physiologic homeostasis. A systems genetics analysis of transcriptomic and functional data from a cohort of diverse, inbred strains of mice predicted that coagulation factor XI (FXI), a liver-derived protein, protects against diastolic dysfunction, a key trait of heart failure with preserved ejection fraction. This was confirmed using gain- and loss-of-function studies, and FXI was found to activate the bone morphogenetic protein (BMP)-SMAD1/5 pathway in the heart. The proteolytic activity of FXI is required for the cleavage and activation of extracellular matrix-associated BMP7 in the heart, thus inhibiting genes involved in inflammation and fibrosis. Our results reveal a protective role of FXI in heart injury that is distinct from its role in coagulation.

Cardiac risk factors limiting survival to liver transplantation in patients with nonalcoholic fatty liver disease

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) describes the hepatic manifestations of metabolic syndrome, which is estimated to affect 25% of adults, and currently represents the second most common indication for liver transplant in the United States. Studies have shown that patients with NAFLD are at an increased risk for heart failure, arrhythmia, and coronary artery disease (CAD), which may impact outcomes of liver transplantation. However, it remains unclear whether the presence of cardiac disease affects survival prior to liver transplant. If so, this would represent an important opportunity to optimize cardiac status and improve outcomes before liver transplant.

AIM

To identify cardiac factors that impact survival to liver transplantation in patients with NAFLD and on the transplant waitlist.

METHODS

The aim of this study was to identify cardiac risk factors that limit survival to transplant in patients with NAFLD. We performed a retrospective analysis of patients with NAFLD listed for liver transplant at a tertiary academic medical center in the United States from January 2015 to January 2021, identified through United Network of Organ Sharing registry. Exclusion criteria included a concurrent etiology of liver disease and removal from the transplant list due to chemical dependency, lack of social support, improvement in liver disease, or being lost to follow-up. We manually reviewed patient charts including electrocardiogram, echocardiogram, and cardiac catheterization reports as well as physician notes to identify cardiac disease states (i.e., heart failure, arrhythmia, valvular disease and CAD) and other related diagnoses. We performed a survival analysis by Cox proportional hazards regression model to analyze the association between cardiac factors at the time listed for transplant and death or clinical deterioration prior to transplant.

RESULTS

Between January 2015 and January 2021, 265 patients with nonalcoholic fatty liver disease were listed for liver transplant at our institution. Our patient sample had a median age of 63 and an even distribution between sexes. The median Model for End-Stage Liver Disease (MELD) score was 17 and the median body mass index was 31.6. Of these 265 patients, 197 (74.3%) survived to transplant and 68 (25.7%) died or clinically deteriorated prior to transplant. The presence of mild or moderate CAD represented a hazard ratio of 2.013 (95%CI 1.078-3.759, P = 0.029) for death or clinical deterioration when compared to patients without CAD, after adjustment for age, sex, and MELD. MELD represented an adjusted hazard ratio of 1.188.

CONCLUSION

Mild or moderate CAD represents a hazard for waitlist mortality prior to liver transplant in patients with NAFLD. Aggressive management of CAD may be needed to improve patient outcomes.

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.

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 Defined by Fatty Liver Index and Incidence of Heart Failure in the Korean Population: A Nationwide Cohort Study

Fatty liver index (FLI) is a simple and useful index that evaluates non-alcoholic fatty liver disease (NAFLD), particularly in large epidemiologic studies. Heart failure (HF) is becoming a burden to public health as the global trend toward an aging society continues. Thus, we investigated the effect of FLI on the incidence of HF using large cohort data from the Korean National Health Insurance health database. Methods and Results: A total of 7,958,538 subjects aged over 19 years without baseline HF (men = 4,142,264 and women = 3,816,274) were included. Anthropometric and biochemical measurements were evaluated. FLI scores were calculated and FLI ≥ 60 was considered as having NAFLD. Hazard ratios (HRs) and 95% confidence intervals (CIs) for HF incidence were analysed using multivariable time-dependent Cox proportional hazard models. During a mean follow up of 8.26 years, 17,104 participants developed HF. The FLI components associated with the incidence of HF and FLI showed a causal relationship with HF; the FLI ≥ 60 group had a higher HR for HF (HR 1.493; 95% CIs 1.41−1.581) than the FLI < 30 group. Subgroup analysis showed that fatty liver (FLI ≥ 60) with age ≥ 65 years or women displayed higher HR for HF than fatty liver with age < 65 or men, respectively. An increase in FLI score significantly increased the HR for HF except for those with a FLI score change from <30 to 30−60. Conclusion: NAFLD defined by FLI and increase in FLI score were associated with the incidence of HF. Further detailed prospective studies are needed.

The National Consensus statement on the management of adult patients with non-alcoholic fatty liver disease and main comorbidities

The National Consensus was prepared with the participation of the National Medical Association for the Study of the Multimorbidity, Russian Scientific Liver Society, Russian Association of Endocrinologists, Russian Association of Gerontologists and Geriatricians, National Society for Preventive Cardiology, Professional Foundation for the Promotion of Medicine Fund PROFMEDFORUM. The aim of the multidisciplinary consensus is a detailed analysis of the course of non-alcoholic fatty liver disease (NAFLD) and the main associated conditions. The definition of NAFLD is given, its prevalence is described, methods for diagnosing its components such as steatosis, inflammation and fibrosis are described. The association of NAFLD with a number of cardio-metabolic diseases (arterial hypertension, atherosclerosis, thrombotic complications, type 2 diabetes mellitus (T2DM), obesity, dyslipidemia, etc.), chronic kidney disease (CKD) and the risk of developing hepatocellular cancer (HCC) were analyzed. The review of non-drug methods of treatment of NAFLD and modern opportunities of pharmacotherapy are presented. The possibilities of new molecules in the treatment of NAFLD are considered: agonists of nuclear receptors, antagonists of pro-inflammatory molecules, etc. The positive properties and disadvantages of currently used drugs (vitamin E, thiazolidinediones, etc.) are described. Special attention is paid to the multi-target ursodeoxycholic acid (UDCA) molecule in the complex treatment of NAFLD as a multifactorial disease. Its anti-inflammatory, anti-oxidant and cytoprotective properties, the ability to reduce steatosis an independent risk factor for the development of cardiovascular pathology, reduce inflammation and hepatic fibrosis through the modulation of autophagy are considered. The ability of UDCA to influence glucose and lipid homeostasis and to have an anticarcinogenic effect has been demonstrated. The Consensus statement has advanced provisions for practitioners to optimize the diagnosis and treatment of NAFLD and related common pathogenetic links of cardio-metabolic diseases.

Non-alcoholic fatty liver disease-related risk of cardiovascular disease and other cardiac complications

BACKGROUND/AIM

Non-alcoholic fatty liver disease (NAFLD) affects approximately 25% of the global adult population. The aim of this narrative review is to describe the associations between NAFLD and cardiovascular disease (CVD), arrhythmias, cardiac conduction defects, myocardial remodelling and heart failure. We also discuss the potential mechanisms that mediate or attenuate the strength of these associations, and briefly summarize the effect of treatments that both ameliorate NAFLD and decrease risk of CVD.

METHODS

Searches of PubMed were performed by the two authors using the terms listed in Appendix. We limited the timeframe to the last decade due to the vast amount of research in the field (up to April 2021) for meta-analyses, reviews and original papers. Only articles published in English were considered.

RESULTS

NAFLD is associated with an increased risk of fatal/non-fatal CVD events and other cardiac and arrhythmic complications (left ventricular hypertrophy, aortic-valve sclerosis and certain arrhythmias), independently of common CVD risk factors. There are probably several underlying mechanisms, including hepatic/systemic insulin resistance, atherogenic dyslipidaemia, hypertension and pro-atherogenic, pro-coagulant and pro-inflammatory mediators released from the steatotic/inflamed liver that may be involved. Some genetic polymorphisms, such as PNPLA3 (rs738409 C>G) and TM6SF2 (rs58542926 C>T), may worsen the liver disease, but also attenuate the strength of the association between NAFLD and CVD, possibly via their effects on lipoprotein metabolism. Of the currently tested drugs for treating NAFLD that also benefit the vasculature, pioglitazone and GLP-1 receptor agonists are the most promising.

CONCLUSIONS

The complex interplay between the liver and cardiometabolic risk factors contributes to CVD, arrhythmias and cardiac disease in NAFLD. There is an urgent need for a multidisciplinary approach to manage both liver disease and cardiometabolic risk, and to test the cardiovascular and cardiac effects of new drugs for NAFLD.

Risk of Heart Failure in Patients With Nonalcoholic Fatty Liver Disease: JACC Review Topic of the Week

Heart failure (HF) and nonalcoholic fatty liver disease (NAFLD) are 2 conditions that have become important global public health problems. Emerging evidence supports a strong and independent association between NAFLD and the risk of new-onset HF, and there are multiple potential pathophysiological mechanisms by which NAFLD may increase risk of new-onset HF. The magnitude of this risk parallels the underlying severity of NAFLD, especially the level of liver fibrosis. Patients with NAFLD develop accelerated coronary atherosclerosis, myocardial alterations (mainly cardiac remodeling and hypertrophy), and certain arrhythmias (mainly atrial fibrillation), which may precede and promote the development of new-onset HF. This brief narrative review aims to provide an overview of the association between NAFLD and increased risk of new-onset HF, discuss the underlying mechanisms that link these 2 diseases, and summarize targeted pharmacological treatments for NAFLD that might also reduce the risk of HF.

Comprehensive Transcriptome Profiling of NAFLD- and NASH-Induced Skeletal Muscle Dysfunction

Nonalcoholic fatty liver disease (NAFLD), characterized by extensive triglyceride accumulation in hepatocytes, may progress to nonalcoholic steatohepatitis (NASH) with liver fibrosis and inflammation and increase the risk of cirrhosis, cancer, and death. It has been reported that physical exercise is effective in ameliorating NAFLD and NASH, while skeletal muscle dysfunctions, including lipid deposition and weakness, are accompanied with NAFLD and NASH. However, the molecular characteristics and alterations in skeletal muscle in the progress of NAFLD and NASH remain unclear. In the present study, we provide a comprehensive analysis on the similarity and heterogeneity of quadriceps muscle in NAFLD and NASH mice models by RNA sequencing. Importantly, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway functional enrichment analysis revealed that NAFLD and NASH led to impaired glucose and lipid metabolism and deteriorated functionality in skeletal muscle. Besides this, we identified that myokines possibly mediate the crosstalk between muscles and other metabolic organs in pathological conditions. Overall, our analysis revealed a comprehensive understanding of the molecular signature of skeletal muscles in NAFLD and NASH, thus providing a basis for physical exercise as an intervention against liver diseases.

Heart Failure with Preserved Ejection Fraction and Obstructive Sleep Apnea: A Novel Paradigm for Additional Cardiovascular Benefit of SGLT2 Inhibitors in Subjects With or Without Type 2 Diabetes

After examining the complex interplay between heart failure (HF) in its various clinical forms, metabolic disorders like nonalcoholic fatty liver disease (NAFLD), and obstructive sleep apnea (OSA) syndrome, in this mini-review we described possible favorable effects of sodium-glucose cotransporter 2 inhibitors (SGLT2is) on HF with preserved (i.e., ≥ 50%) ejection fraction (HFpEF) through enhanced cardiorenal function and visceral-subcutaneous body fat redistribution. In greater detail, on the basis of pathophysiological mechanisms underlying OSA onset and the direct positive SGLT2i effect on renal function benefiting chronic kidney disease, we emphasized the promising role of SGLT2is in prevention, rehabilitation, and treatment of patients with OSA regardless of coexisting type 2 diabetes (T2DM). Indeed, SGLT2is enhance lipolysis and fatty acid beta-oxidation. These phenomena might prevent OSA by reducing the size of visceral and subcutaneous adipose tissue and, as proven in humans and animals with T2DM, counteract NAFLD onset and progression. The aforementioned mechanisms may represent an additional SGLT2i cardioprotective effect in terms of HFpEF prevention in patients with OSA, whose NAFLD prevalence is estimated to be over 50%.

The association of hepatic steatosis and fibrosis with heart failure and mortality

Background

Nonalcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic disease and independently affects the development of cardiovascular (CV) disease. We investigated whether hepatic steatosis and/or fibrosis are associated with the development of incident heart failure (iHF), hospitalized HF (hHF), mortality, and CV death in both the general population and HF patients.

Methods

We analyzed 778,739 individuals without HF and 7445 patients with pre-existing HF aged 40 to 80 years who underwent a national health check-up from January 2009 to December 2012. The presence of hepatic steatosis and advanced hepatic fibrosis was determined using cutoff values for fatty liver index (FLI) and BARD score. We evaluated the association of FLI or BARD score with the development of iHF, hHF, mortality and CV death using multivariable-adjusted Cox regression models.

Results

A total of 28,524 (3.7%) individuals in the general population and 1422 (19.1%) pre-existing HF patients developed iHF and hHF respectively. In the multivariable-adjusted model, participants with an FLI ≥ 60 were at increased risk for iHF (hazard ratio [HR], 95% confidence interval [CI], 1.30, 1.24–1.36), hHF (HR 1.54, 95% CI 1.44–1.66), all-cause mortality (HR 1.62, 95% CI 1.54–1.70), and CV mortality (HR 1.41 95% CI 1.22–1.63) in the general population and hHF (HR 1.26, 95% CI 1.21–1.54) and all-cause mortality (HR 1.54 95% CI 1.24–1.92) in the HF patient group compared with an FLI < 20. Among participants with NAFLD, advanced liver fibrosis was associated with increased risk for iHF, hHF, and all-cause mortality in the general population and all-cause mortality and CV mortality in the HF patient group (all p < 0.05).

Conclusion

Hepatic steatosis and/or advanced fibrosis as assessed by FLI and BARD score was significantly associated with the risk of HF and mortality.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01374-8.

Nonalcoholic Fatty Liver Disease: An Emerging Driver of Cardiac Arrhythmia

Cardiac arrhythmias and the resulting sudden cardiac death are significant cardiovascular complications that continue to impose a heavy burden on patients and society. An emerging body of evidence indicates that nonalcoholic fatty liver disease (NAFLD) is closely associated with the risk of cardiac arrhythmias, independent of other conventional cardiometabolic comorbidities. Although most studies focus on the relationship between NAFLD and atrial fibrillation, associations with ventricular arrhythmias and cardiac conduction defects have also been reported. Mechanistic investigations suggest that a number of NAFLD-related pathophysiological alterations may potentially elicit structural, electrical, and autonomic remodeling in the heart, contributing to arrhythmogenic substrates in the heart. NAFLD is now the most common liver and metabolic disease in the world. However, the upsurge in the prevalence of NAFLD as an emerging risk factor for cardiac arrhythmias has received little attention. In this review, we summarize the clinical evidence and putative pathophysiological mechanisms for the emerging roles of NAFLD in cardiac arrhythmias, with the purpose of highlighting the notion that NAFLD may serve as an independent risk factor and a potential driving force in the development and progression of cardiac arrhythmias.

Visceral adiposity, muscle composition, and exercise tolerance in heart failure with preserved ejection fraction

Aims

Visceral adipose tissue (AT) promotes inflammation and may be associated with disease progression in heart failure with preserved ejection fraction (HFpEF). We characterized regional AT distribution in HFpEF patients and controls and analysed associations with co‐morbidities and exercise tolerance.

Methods and results

Magnetic resonance imaging was performed to quantify epicardial, liver, abdominal, and thigh skeletal muscle AT. We assessed New York Heart Association (NYHA) class, 6 min walk distance, and global well‐being score. Multivariable linear regression models adjusting for body surface area were used. We studied 55 HFpEF patients (41 women, mean age 67 ± 11 years) and 33 controls (21 women, mean age 57 ± 10 years). Epicardial AT (median [interquartile range] 4.6 [2.0] vs. 3.2 [1.4] mm, P < 0.001), thigh intermuscular fat (11.0 [11.5] vs. 5.0 [2.7] cm², P < 0.001) and liver fat fraction (6.4% [6.1] vs. 4.1% [5.5], P = 0.001) were higher in HFpEF patients than controls. Women with HFpEF had higher abdominal and thigh subcutaneous AT than men. Greater thigh intermuscular fat was associated with higher blood pressure (β [SE] 0.73 [0.17], P < 0.001) and diabetes (odds ratio [95% confidence interval] 1.2 [1.0–1.5], P = 0.03). Greater thigh intramuscular fat was associated with both worse NYHA class (β [SE] 2.7 [1.0], P = 0.01) and shorter 6 min walk distance (β [SE] −4.1 [1.9], P = 0.03), and greater epicardial AT (β [SE] −0.2 [0.1], P < 0.001) and liver fat fraction (β [SE] −0.4 [0.2], P = 0.04) were associated with lower global well‐being score.

Conclusions

Heart failure with preserved ejection fraction patients have increased epicardial, liver, and skeletal muscle fat compared with controls out of proportion to their increased body size, and adiposity was associated with worse NYHA class and exercise tolerance in HFpEF. These results provide the basis for further investigation into the effect of interventions to reduce regional AT distribution in relation to HFpEF symptoms and pathophysiology.

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.

Elafibranor improves diet-induced nonalcoholic steatohepatitis associated with heart failure with preserved ejection fraction in Golden Syrian hamsters

BACKGROUND

Cardiovascular disease is the leading cause of deaths in nonalcoholic steatohepatitis (NASH) patients. Mouse models, while widely used for drug development, do not fully replicate human NASH nor integrate the associated cardiac dysfunction, i.e. heart failure with preserved ejection fraction (HFpEF). To overcome these limitations, we established a nutritional hamster model developing both NASH and HFpEF. We then evaluated the effects of the dual peroxisome proliferator activated receptor alpha/delta agonist elafibranor developed for the treatment of NASH patients.

METHODS

Male Golden Syrian hamsters were fed for 10 to 20 weeks with a free choice diet, which presents hamsters with a choice between control chow diet with normal drinking water or a high fat/high cholesterol diet with 10% fructose enriched drinking water. Biochemistry, histology and echocardiography analysis were performed to characterize NASH and HFpEF. Once the model was validated, elafibranor was evaluated at 15 mg/kg/day orally QD for 5 weeks.

RESULTS

Hamsters fed a free choice diet for up to 20 weeks developed NASH, including hepatocyte ballooning (as confirmed with cytokeratin-18 immunostaining), bridging fibrosis, and a severe diastolic dysfunction with restrictive profile, but preserved ejection fraction. Elafibranor resolved NASH, with significant reduction in ballooning and fibrosis scores, and improved diastolic dysfunction with significant reduction in E/A and E/E' ratios.

CONCLUSION

Our data demonstrate that the free choice diet induced NASH hamster model replicates the human phenotype and will be useful for validating novel drug candidates for the treatment of NASH and associated HFpEF.

NAFLD and Cardiovascular Diseases: Epidemiological, Mechanistic and Therapeutic Considerations

Overwhelming evidence suggests an association of cardiovascular disease (CVD) with non-alcoholic fatty liver disease (NAFLD); however, the underlying mechanisms remain largely speculative. It is, however, likely that common mechanisms contribute to the development of CVD and NAFLD, with lifestyle factors such as smoking, sedentary lifestyle with poor nutrition habits and physical inactivity being major candidates. These behavioral factors, on a predisposing genetic background, trigger changes in gut microbiota, inflammation, dyslipidemia and oxidative stress, leading to metabolic syndrome, diabetes and obesity as well as atherosclerosis. Treatment options to counteract both the progression and development of CVD and NAFLD include lifestyle interventions, optimal medical therapy of comorbid conditions and, as final possibility, bariatric surgery. As no causal pharmacotherapy of NAFLD is available, further research is urgently needed to address the unmet need of a growing population with NAFLD and CVD.

The functional medicine approach to atrial fibrillation: can a cure for atrial fibrillation be found in the gut?

PURPOSE OF REVIEW

The importance of addressing the proximal causes of atrial fibrillation is recognized, yet frustration with the currently applied preventive measures is high. This review describes the functional medicine model (FMM), which identifies the proximal causes of atrial fibrillation at the level of gene-environment interaction.

RECENT FINDINGS

The pathological processes leading to atrial fibrillation sustaining disorder have been elucidated in translational studies and are described as 'nodal points.' Examples are inflammation, oxidative stress, autoimmune mechanisms, and visceral adiposity. These same nodal points also cause disorder that results in atrial fibrillation-related complications and the development of atrial fibrillation-associated diseases. These nodal points vary from patient to patient and can be identified by careful evaluation of the patients clinical phenotype.

SUMMARY

The application of the FMM identifies the gene--environment interactions that facilitate the patients nodal points and corrects them with emphasis on personalized diet, nutrition, and lifestyle changes.

NAFLD and cardiovascular diseases: a clinical review

Non-alcoholic fatty liver DISEASE (NAFLD) is the most common chronic liver disease in Western countries and affects approximately 25% of the adult population. Since NAFLD is frequently associated with further metabolic comorbidities such as obesity, type 2 diabetes mellitus, or dyslipidemia, it is generally considered as the hepatic manifestation of the metabolic syndrome. In addition to its potential to cause liver-related morbidity and mortality, NAFLD is also associated with subclinical and clinical cardiovascular disease (CVD). Growing evidence indicates that patients with NAFLD are at substantial risk for the development of hypertension, coronary heart disease, cardiomyopathy, and cardiac arrhythmias, which clinically result in increased cardiovascular morbidity and mortality. The natural history of NAFLD is variable and the vast majority of patients will not progress from simple steatosis to fibrosis and end stage liver disease. However, patients with progressive forms of NAFLD, including non-alcoholic steatohepatitis (NASH) and/or advanced fibrosis, as well as NAFLD patients with concomitant types 2 diabetes are at highest risk for CVD. This review describes the underlying pathophysiological mechanisms linking NAFLD and CVD, discusses the role of NAFLD as a metabolic dysfunction associated cardiovascular risk factor, and focuses on common cardiovascular manifestations in NAFLD patients.