From Left Ventricular Hypertrophy to Congestive Heart Failure: Management of Hypertensive Heart Disease

3D echocardiography derived reference values and determinants of left ventricular twist and torsion from the population-based STAAB cohort study

Left ventricular (LV) rotational function parameters provide in-depth information about LV mechanical function as well as prognostic information. Using three-dimensional (3D) echocardiography, we identified determinants of LV "twist" and "torsion", and established reference values using a large population-based cohort. 3D echocardiography images were recorded in n = 2803 subjects within the prospective STAAB cohort study investigating a representative age- and sex-stratified sample of residents of the city of Würzburg, aged 30-79 years, without history of heart failure. Valid 3D image analysis was performed in n = 1831 (65.3%) subjects (mean age 57 ± 11 years, 49.3% women). Using general linear models, we identified determinants of LV twist and torsion: there was a positive association between LV rotational parameters and age, female sex, and blood pressure but a negative association with body weight. From a subset of 479 apparently healthy individuals exhibiting no cardiovascular (CV) risk factors or CV disease (mean age 52 ± 10 years, 56.4% women), we derived reference percentiles for twist and torsion. LV rotation is determined by a complex interplay of sub-endocardial and sub-epicardial fibers which might be affected differentially by potential risk factors. We found a differential association with respective determinants as LV rotational parameters increased with age and with higher blood pressure but decreased with higher body weight. Further research is needed to elucidate these associations in more detail and to determine the additional information contributed by twist and torsion. To facilitate respective attempts and to set an individual's results in relation to a population-based reference, we derived normal values for twist and torsion from a sub-collective of healthy individuals.

Association Between Longitudinal Changes in Left Ventricular Structure and Function and 24-Hour Urinary Free Cortisol in Essential Hypertension

This study aimed to investigate the associations between 24-hour urinary cortisol levels (24 h-UFC) and alterations in left ventricular (LV) structure and function in patients with essential hypertension. A prospective cohort study was conducted, including 315 patients with essential hypertension who underwent baseline 24 h-UFC measurement and echocardiographic evaluation of left ventricular mass (LVM), left ventricular ejection fraction (LVEF), and the E/e' ratio. Over a mean follow-up period of 28.54 ± 14.21 months, patients were grouped into tertiles based on baseline 24 h-UFC levels. Higher baseline 24 h-UFC levels were significantly associated with greater increases in LVM and E/e', reflecting adverse LV remodeling and diastolic dysfunction. These associations persisted after adjusting for potential confounders, including age, gender, baseline blood pressure, and their changes during follow-up. Moreover, patients in the highest 24 h-UFC tertile showed an increased prevalence of LV hypertrophy, contrasting with a reduction observed in the lower tertiles. These findings underscore the independent role of elevated 24 h-UFC levels in driving adverse cardiac structural and functional changes in essential hypertension.

The Role of NT-proBNP Levels in the Diagnosis of Hypertensive Heart Disease

Hypertension is a major risk factor of various cardiac complications, including hypertensive heart disease (HHD). This condition can lead to a number of structural and functional changes in the heart, such as left ventricular hypertrophy, diastolic dysfunction, and, eventually, systolic dysfunction. In the management of hypertensive heart disease, early diagnosis and appropriate treatment are crucial for preventing the progression to congestive heart failure. One potential diagnostic marker that has gained attention in recent years is the N-terminal pro-brain natriuretic peptide (NT-proBNP). The natriuretic peptides, including the brain natriuretic peptide (BNP) and its inactive N-terminal fragment, are secreted by the myocardium in response to increased wall stress and volume overload. In patients with hypertensive heart disease, increased NT-proBNP levels may reflect the structural and functional changes occurring in the myocardium as a result of chronic pressure overload. Several studies have investigated the diagnostic utility of NT-proBNP in hypertensive heart disease. NT-proBNP levels can be a useful adjunct in the diagnosis of hypertensive heart disease, particularly in the assessment of diastolic dysfunction and left ventricular hypertrophy. This review paper explores the role of NT-proBNP levels in the diagnosis of hypertensive heart disease.

SARS-CoV-2 pathogenesis in an angiotensin II-induced heart-on-a-chip disease model and extracellular vesicle screening

Adverse cardiac outcomes in COVID-19 patients, particularly those with preexisting cardiac disease, motivate the development of human cell-based organ-on-a-chip models to recapitulate cardiac injury and dysfunction and for screening of cardioprotective therapeutics. Here, we developed a heart-on-a-chip model to study the pathogenesis of SARS-CoV-2 in healthy myocardium established from human induced pluripotent stem cell (iPSC)-derived cardiomyocytes and a cardiac dysfunction model, mimicking aspects of preexisting hypertensive disease induced by angiotensin II (Ang II). We recapitulated cytopathic features of SARS-CoV-2-induced cardiac damage, including progressively impaired contractile function and calcium handling, apoptosis, and sarcomere disarray. SARS-CoV-2 presence in Ang II-treated hearts-on-a-chip decreased contractile force with earlier onset of contractile dysfunction and profoundly enhanced inflammatory cytokines compared to SARS-CoV-2 alone. Toward the development of potential therapeutics, we evaluated the cardioprotective effects of extracellular vesicles (EVs) from human iPSC which alleviated the impairment of contractile force, decreased apoptosis, reduced the disruption of sarcomeric proteins, and enhanced beta-oxidation gene expression. Viral load was not affected by either Ang II or EV treatment. We identified MicroRNAs miR-20a-5p and miR-19a-3p as potential mediators of cardioprotective effects of these EVs.

A study on the application of radiomics based on cardiac MR non-enhanced cine sequence in the early diagnosis of hypertensive heart disease

BACKGROUND

The prevalence of hypertensive heart disease (HHD) is high and there is currently no easy way to detect early HHD. Explore the application of radiomics using cardiac magnetic resonance (CMR) non-enhanced cine sequences in diagnosing HHD and latent cardiac changes caused by hypertension.

METHODS

132 patients who underwent CMR scanning were divided into groups: HHD (42), hypertension with normal cardiac structure and function (HWN) group (46), and normal control (NOR) group (44). Myocardial regions of the end-diastolic (ED) and end-systolic (ES) phases of the CMR short-axis cine sequence images were segmented into regions of interest (ROI). Three feature subsets (ED, ES, and ED combined with ES) were established after radiomic least absolute shrinkage and selection operator feature selection. Nine radiomic models were built using random forest (RF), support vector machine (SVM), and naive Bayes. Model performance was analyzed using receiver operating characteristic curves, and metrics like accuracy, area under the curve (AUC), precision, recall, and specificity.

RESULTS

The feature subsets included first-order, shape, and texture features. SVM of ED combined with ES achieved the highest accuracy (0.833), with a macro-average AUC of 0.941. AUCs for HHD, HWN, and NOR identification were 0.967, 0.876, and 0.963, respectively. Precisions were 0.972, 0.740, and 0.826; recalls were 0.833, 0.804, and 0.863, respectively; and specificities were 0.989, 0.863, and 0.909, respectively.

CONCLUSIONS

Radiomics technology using CMR non-enhanced cine sequences can detect early cardiac changes due to hypertension. It holds promise for future use in screening for latent cardiac damage in early HHD.

Importance of B-Type Natriuretic Peptide in the Detection of Patients With Structural Heart Disease in a Primary Care Setting

BACKGROUND

Early detection and intervention for preclinical heart failure (HF) are crucial for restraining the potential increase in patients with HF. Thus, we designed and conducted a single-center retrospective cohort study to confirm the efficacy of B-type natriuretic peptide (BNP) for the early detection of preclinical HF in a primary care setting.

METHODS AND RESULTS

We investigated 477 patients with no prior diagnosis of HF who were under the care of general practitioners. These patients were categorized into 4 groups based on BNP concentrations: Category 1, 0 pg/mL≤BNP≤35 pg/mL; Category 2, 35 pg/mL200 pg/mL. There was a marked and statistically significant increase in the prevalence of preclinical HF with increasing BNP categories: 19.9%, 57.9%, 87.5%, and 96.0% in Categories 1, 2, 3, and 4, respectively. Compared with Category 1, the odds ratio of preclinical HF in Categories 2, 3, and 4 was determined to be 5.56 (95% confidence interval [CI] 3.57-8.67), 23.70 (95% CI 8.91-63.11), and 171.77 (95% CI 10.31-2,861.93), respectively.

CONCLUSIONS

Measuring BNP is a valuable tool for the early detection of preclinical HF in primary care settings. Proactive testing in patients at high risk of HF could play a crucial role in addressing the impending HF pandemic.

Relationship of Left Ventricular Mass to Lean Body Mass in the Obese Pediatric Population

Our primary aim was to investigate the relationship between LVM and anthropometric measures including lean body mass (LBM) in obese pediatric subjects compared to normal weight controls. A retrospective chart review identified subjects 2-18 years old who were normotensive and had normal echocardiograms between 1995 and 2020 at Boston Children's Hospital. LVM was calculated with the 5/6 area length rule from 2D echocardiograms. LBM was calculated with equations derived from dual-energy X-ray absorptiometry. Of the 2217 subjects who met inclusion criteria, 203 were obese and 2014 had normal weight. The median age was 11.9 (2.0-18.9); 46% were female. The median LVM was 94.5 g (59.3-134.3) in obese subjects vs. 78.0 g (51.5-107.7) in controls. The median LBM was 37.2 kg (18.9-50.6) in obese subjects vs. 30.5 kg (17.6-40.8) in controls. In control and obese subjects, LBM had the strongest correlation to LVM (R2 0.86, P < 0.001) and (R2 0.87, P < 0.001), respectively. There was at most a modest correlation between tissue Doppler velocity z-scores and LV mass, and the largest was Septal E' z-score in obese subjects (r = - 0.31, P = 0.006). In this cohort, LBM was found to have the strongest relationship to LVM in obese subjects. The largest correlation between tissue Doppler velocity z-scores and LV mass was Septal E' z-score. Future studies will evaluate which measurements are more closely aligned with clinical outcomes in obese children.

Association between obesity and new-onset heart failure among patients with hypertension in Thailand

BACKGROUND

In Thailand, the epidemiological data on the relationship between obesity and heart failure (HF) among high-risk populations was limited. We assessed the association between body mass index (BMI) and the new-onset HF among people with hypertension (HTN), and also assessed the effect modifier of uncontrolled HTN on this association.

METHODS

We analyzed the data obtained from the 2018 Thailand DM/HT study database. Thai people with HTN aged 20 years and older receiving continuous care at outpatient clinics in hospitals nationwide were included. The new-onset HF was defined regarding the ICD-10 as I50 in the medical records within 12 months. Obesity was defined as BMI ≥ 25 kg/m2. Multivariable log-binomial regression analysis was used to determine the association between BMI and new-onset HF and presented as the adjusted risk ratio (aRR) and 95% confidence interval (CI).

RESULTS

A total of 35,756 participants were included in the analysis. In all, 50.0% of the participants had BP control for the last two consecutive visits. The mean BMI was 25.1 ± 4.7 kg/m2. New-onset HF occurred in 75 participants (0.21%; 95% CI 0.17-0.26). After adjusting for potential confounders, an elevated BMI was associated with new-onset HF (p value for quadratic trend < 0.001). In comparison with participants with normal BMI (18.5-22.9 kg/m2), the aRR for new-onset HF was 1.57 (95% CI 0.80-3.07) and 3.97 (95% CI 1.95-8.10) in those with BMI 25.0-29.9, and ≥ 30.0 kg/m2. For participants with obesity, aRR for new-onset HF was 2.05 (95% CI 1.24-3.39) compared to non-obese participants. The study found that among patients with control BP, obesity was associated with a higher risk of new-onset HF with an adjusted RR of 2.33 (95% CI 1.12-4.83). For those with uncontrolled BP, the adjusted RR was 1.83 (95% CI 0.93-3.58), but there was no heterogeneity with p value = 0.642.

CONCLUSION

An increased BMI had a higher risk for new-onset HF among Thai people with HTN. Obesity was independently associated with new-onset HF among people with HTN, regardless of uncontrolled HTN. Our findings highlight that weight reduction is crucial for mitigating the risk of HF development in HTN patients, regardless of their BP control status.

High left ventricular mass associated with increased risk of incident diabetes

Evidence for the role of electrocardiography or echocardiography in determining left ventricular hypertrophy for the risk of diabetes is still controversial. We aimed to explore whether left ventricular mass, as measured by these methods, is associated with the risk of diabetes in a community population. We recruited 2696 participants aged 35 years or older without diabetes who had undergone screening with electrocardiography and echocardiography. Left ventricular mass index (LVMI) was calculated using a formula, and participants were divided into tertiles based on their LVMI tertiles. During a median follow-up period of median, 8.9 years, a total of 405 participants developed diabetes. The incidence and risk of diabetes significantly increased with higher LVMI tertiles. Multivariate Cox regression analysis demonstrated that individuals in the highest LVMI tertile had a greater likelihood of developing incident diabetes, with a hazard ratio of 1.40 (95% CI 1.06-1.91), even after adjusting related covariates. The highest risk of diabetes was observed in the presence of both the uppermost LVMI tertile and electrocardiographically determined left ventricular hypertrophy for the Chinese population. Left ventricular hypertrophy identified by either electrocardiography or echo may serve as a surrogate marker for identifying the risk of diabetes in clinical practice.

The Seattle Heart Failure Model in Kidney Transplant Recipients

Cardiovascular disease is the leading cause of mortality following kidney transplantation. Heart failure affects 17-21% of patients with chronic kidney disease and increases along with time receiving dialysis. The Seattle Heart Failure Model (SHFM) is a validated mortality risk model for heart failure patients that incorporates clinical, therapeutic, and laboratory parameters but does not include measures of kidney function. We applied the SHFM to patients with end-stage renal disease (ESRD) who were being evaluated for kidney transplantation to determine if the model was associated with post-transplant mortality. This retrospective single-center study analyzed survival among 360 adult deceased-donor kidney transplant recipients. Cox regression was used to model post-transplant patient survival. Our findings indicated that a 1.0-point increase in the adapted SHFM score was significantly associated with post-transplant mortality (HR 1.76, 95% CI = 1.10-2.83, p = 0.02), independently of the Kidney Donor Profile Index and Estimated Post-Transplant Survival. Individual covariates of the SHFM were evaluated in univariate analyses, and age, sodium, cholesterol, and lymphocyte count were significantly related to mortality. This study provides preliminary evidence that an adapted SHFM score could be a useful tool in evaluating mortality risk post-transplant in patients with ESRD.

Early reverse remodeling of left heart morphology and function evaluated by cardiac magnetic resonance in hypertrophic obstructive cardiomyopathy after transapical beating-heart septal myectomy

PURPOSE

This study aimed to evaluate the early morphology and function of the left heart in hypertrophic obstructive cardiomyopathy (HOCM) after transapical beating-heart septal myectomy (TA-BSM) using cardiovascular magnetic resonance (CMR).

MATERIALS AND METHODS

Between April 2022 and January 2023, HOCM patients who underwent CMR before and 3 months after TA-BSM were prospectively and consecutively enrolled in the study. Preoperative and postoperative cardiac morphological and functional parameters, including those for the left atrium (LA) and left ventricle (LV), were compared. The left ventricular remodeling index (LVRI) was defined as the ratio between left ventricular mass (LVM) and left ventricular end-diastolic volume (LVEDV). Healthy participants with a similar age and sex distribution were enrolled for comparison. Pearson or Spearman correlation analysis was used to investigate the relationships between the parameters and LVRI. Last, univariate and multivariate linear regression identified variables associated with the LVM index (LVMI) and LVRI.

RESULTS

Forty-one patients (mean age ± standard deviation, 46 ± 2 years; 27 males) and 41 healthy control participants were evaluated. Eighteen (44%) HOCM patients were classified as having a sigmoid septum, and 23 patients had a reverse septal curvature. LA volume, diameter and function were significantly improved postoperatively, but still worse than healthy controls (all p < 0.001). Compared to before the operation, left ventricular wall thickness, left ventricular ejection fraction (LVEF), LVMI, and LVRI decreased after TA-BSM (all p < 0.001). The left ventricular end-diastolic volume index (LVEDVI) and left ventricular end-diastolic diameter (LVEDD) decreased in patients with a sigmoid septum. However, LVEDVI and LVEDD increased in those with a reverse septal curvature (both p < 0.001). In addition, both preoperative and postoperative LVRI was positively correlated with LVMI (r = 0.734 and 0.853, both p < 0.001) and maximum wall thickness (r = 0.679 and 0.676, both p < 0.001), respectively. In the multivariable analysis, the weight of the resected myocardium (adjusted β = 0.476, p = 0.005) and △mitral regurgitation degree (adjusted β = - 0.245, p = 0.040) were associated with △LVRI. Last, the △LVOTG (adjusted β = 0.436, p = 0.018) and baseline LVMI (adjusted β = 0.323, p = 0.040) were independently associated with greater left ventricular mass regression after TA-BSM.

CONCLUSION

CMR confirmed early reverse remodeling of left heart morphology and function in HOCM patients following TA-BSM.

The Left Atrial Area Derived Cardiovascular Magnetic Resonance Left Ventricular Filling Pressure Equation Shows Superiority over Integrated Echocardiography

Background and objectives: Evaluating left ventricular filling pressure (LVFP) plays a crucial role in diagnosing and managing heart failure (HF). While traditional assessment methods involve multi-parametric transthoracic echocardiography (TTE) or right heart catheterisation (RHC), cardiovascular magnetic resonance (CMR) has emerged as a valuable diagnostic tool in HF. This study aimed to assess a simple CMR-derived model to estimate pulmonary capillary wedge pressure (PCWP) in a cohort of patients with suspected or proven heart failure and to investigate its performance in risk-stratifying patients. Materials and methods: A total of 835 patients with breathlessness were evaluated using RHC and CMR and split into derivation (85%) and validation cohorts (15%). Uni-variate and multi-variate linear regression analyses were used to derive a model for PCWP estimation using CMR. The model's performance was evaluated by comparing CMR-derived PCWP with PCWP obtained from RHC. Results: A CMR-derived PCWP incorporating left ventricular mass and the left atrial area (LAA) demonstrated good diagnostic accuracy. The model correctly reclassified 66% of participants whose TTE was 'indeterminate' or 'incorrect' in identifying raised filling pressures. On survival analysis, the CMR-derived PCWP model was predictive for mortality (HR 1.15, 95% CI 1.04-1.28, p = 0.005), which was not the case for PCWP obtained using RHC or TTE. Conclusions: The simplified CMR-derived PCWP model provides an accurate and practical tool for estimating PCWP in patients with suspected or proven heart failure. Its predictive value for mortality suggests the ability to play a valuable adjunctive role in echocardiography, especially in cases with unclear echocardiographic assessment.

Virtual drug screen reveals context-dependent inhibition of cardiomyocyte hypertrophy

BACKGROUND AND PURPOSE

Pathological cardiomyocyte hypertrophy is a response to cardiac stress that typically leads to heart failure. Despite being a primary contributor to pathological cardiac remodelling, the therapeutic space that targets hypertrophy is limited. Here, we apply a network model to virtually screen for FDA-approved drugs that induce or suppress cardiomyocyte hypertrophy.

EXPERIMENTAL APPROACH

A logic-based differential equation model of cardiomyocyte signalling was used to predict drugs that modulate hypertrophy. These predictions were validated against curated experiments from the prior literature. The actions of midostaurin were validated in new experiments using TGFβ- and noradrenaline (NE)-induced hypertrophy in neonatal rat cardiomyocytes.

KEY RESULTS

Model predictions were validated in 60 out of 70 independent experiments from the literature and identify 38 inhibitors of hypertrophy. We additionally predict that the efficacy of drugs that inhibit cardiomyocyte hypertrophy is often context dependent. We predicted that midostaurin inhibits cardiomyocyte hypertrophy induced by TGFβ, but not noradrenaline, exhibiting context dependence. We further validated this prediction by cellular experiments. Network analysis predicted critical roles for the PI3K and RAS pathways in the activity of celecoxib and midostaurin, respectively. We further investigated the polypharmacology and combinatorial pharmacology of drugs. Brigatinib and irbesartan in combination were predicted to synergistically inhibit cardiomyocyte hypertrophy.

CONCLUSION AND IMPLICATIONS

This study provides a well-validated platform for investigating the efficacy of drugs on cardiomyocyte hypertrophy and identifies midostaurin for consideration as an antihypertrophic drug.

Hypertensive heart disease: risk factors, complications and mechanisms

Hypertensive heart disease constitutes functional and structural dysfunction and pathogenesis occurring primarily in the left ventricle, the left atrium and the coronary arteries due to chronic uncontrolled hypertension. Hypertensive heart disease is underreported and the mechanisms underlying its correlates and complications are not well elaborated. In this review, we summarize the current understanding of hypertensive heart disease, we discuss in detail the mechanisms associated with development and complications of hypertensive heart disease especially left ventricular hypertrophy, atrial fibrillation, heart failure and coronary artery disease. We also briefly highlight the role of dietary salt, immunity and genetic predisposition in hypertensive heart disease pathogenesis.

Association between Aldosterone Synthase (CYP11B2) Gene Polymorphism and Hypertension in Pashtun Ethnic Population of Khyber Pakhtunkwha, Pakistan

Genome-wide association studies significantly increased the number of hypertension risk variants; however, most of them focused on European societies. There is lack of such studies in developing countries, including Pakistan. The lack of research studies and the high prevalence of hypertension in the Pakistani community prompted us to design this study. Aldosterone synthase (CYP11B2) was thoroughly studied in different ethnic groups; however, no such study has been conducted in the Pashtun population of Khyber Pakhtunkhwa, Pakistan. In essential hypertension, the aldosterone synthase gene (CYP11B2) plays a significant role. Aldosterone synthesis is affected by both hereditary and environmental factors. Aldosterone synthase (encoded by the CYP11B2 gene) controls the conversion of deoxycorticosterone to aldosterone and, thus, has genetic influences. Polymorphisms in the CYP11B2 gene are linked to an increased risk of hypertension. Previous research on the polymorphism of the aldosterone synthase (CYP11B2) gene and its relationship to hypertension produced inconclusive results. The present study investigates the relationship between CYP11B2 gene polymorphism and hypertension in Pakistan's Pashtun population. We used the nascent exome sequencing method to identify variants associated with hypertension. The research was divided into two phases. In phase one, DNA samples from 200 adult hypertension patients (of age ≥ 30 years) and 200 controls were pooled (n = 200/pool) and subjected to Exome Sequencing. In the second phase, the WES reported SNPs were genotyped using the Mass ARRAY technique to verify and confirm the association between WES-identified SNPs and hypertension. WES identified a total of eight genetic variants in the CYP11B2 gene. The chi-square test and logistic regression analysis were used to estimate the minor allele frequencies (MAFs) and chosen SNPs relationships with hypertension. The frequency of minor allele T was found to be higher in cases compared to the control (42% vs. 30%: p = 0.001) for rs1799998 of CYP11B2 gene, while no significant results (p > 0.05) were observed for the remaining SNPs; rs4536, rs4537, rs4545, rs4543, rs4539, rs4546 and rs6418 showed no positive association with HTN in the studied population (all p > 0.05). Our study findings suggest that rs1799998 increases susceptibly to HTN in the Pashtun population of KP, Pakistan.

Effect of the structural modification of Candesartan with Zinc on hypertension and left ventricular hypertrophy

Hypertension is the most common cause of left ventricular hypertrophy, contributing to heart failure progression. Candesartan (Cand) is an angiotensin receptor antagonist widely used for hypertension treatment. Structural modifications were previously performed by our group using Zinc (ZnCand) as a strategy for improving its pharmacological properties. The measurements showed that ZnCand exerts a stronger interaction with the angiotensin II receptor, type 1 (AT1 receptor), reducing oxidative stress and intracellular calcium flux, a mechanism implied in cell contraction. These results were accompanied by the reduction of the contractile capacity of mesangial cells. In vivo experiments showed that the complex causes a significant decrease in systolic blood pressure after 8 weeks of treatment in spontaneously hypertensive rats (SHR). The reduction of heart hypertrophy was evidenced by echocardiography, the histologic cross-sectional area of cardiomyocytes, collagen content, the B-type natriuretic peptide (BNP) marker and connective tissue growth factor (CTGF) and the matrix metalloproteinase 2 (MMP-2) expression. Besides, the complex restored the redox status. In this study, we demonstrated that the complexation with Zn(II) improves the antihypertensive and cardiac effects of the parental drug.

Hypertensive Heart Disease: A Narrative Review Series-Part 1: Pathophysiology and Microstructural Changes

Sustained hypertension causes structural, functional, and neurohumoral abnormalities in the heart, a disease commonly termed hypertensive heart disease (HHD). Modern concepts of HHD, including processes of remodeling leading to the development of various LVH patterns, HF patterns accompanied by micro- and macrovasculopathies, and heart rhythm and conduction disturbances, are missing in the available definitions, despite copious studies being devoted to the roles of myocardial and vascular fibrosis, and neurohumoral and sympathetic regulation, in HHD development and progression. No comprehensive and generally accepted universal definition and classification of HHD is available to date, implementing diagnostic criteria that incorporate all the possible changes and adaptions to the heart. The aim of this review series is to summarize the relevant literature and data, leading to a proposal of a definition and classification of HHD. This first article reviews the processes of initial myocardial remodeling, and myocardial and vascular fibrosis, occurring in HHD. We discuss important pathophysiological and microstructural changes, the different patterns of fibrosis, and the biomarkers and imaging used to detect fibrosis in HHD. Furthermore, we review the possible methods of targeting myocardial fibrosis in HHD, and highlight areas for further research.

Artificial Intelligence Enabled Classification of Hypertrophic Heart Diseases Using Electrocardiograms

Background

Differentiating among cardiac diseases associated with left ventricular hypertrophy (LVH) informs diagnosis and clinical care.

Objective

To evaluate if artificial intelligence-enabled analysis of the 12-lead electrocardiogram (ECG) facilitates automated detection and classification of LVH.

Methods

We used a pretrained convolutional neural network to derive numerical representations of 12-lead ECG waveforms from patients in a multi-institutional healthcare system who had cardiac diseases associated with LVH (n = 50,709), including cardiac amyloidosis (n = 304), hypertrophic cardiomyopathy (n = 1056), hypertension (n = 20,802), aortic stenosis (n = 446), and other causes (n = 4766). We then regressed LVH etiologies relative to no LVH on age, sex, and the numerical 12-lead representations using logistic regression ("LVH-Net"). To assess deep learning model performance on single-lead data analogous to mobile ECGs, we also developed 2 single-lead deep learning models by training models on lead I ("LVH-Net Lead I") or lead II ("LVH-Net Lead II") from the 12-lead ECG. We compared the performance of the LVH-Net models to alternative models fit on (1) age, sex, and standard ECG measures, and (2) clinical ECG-based rules for diagnosing LVH.

Results

The areas under the receiver operator characteristic curve of LVH-Net by specific LVH etiology were cardiac amyloidosis 0.95 [95% CI, 0.93-0.97], hypertrophic cardiomyopathy 0.92 [95% CI, 0.90-0.94], aortic stenosis LVH 0.90 [95% CI, 0.88-0.92], hypertensive LVH 0.76 [95% CI, 0.76-0.77], and other LVH 0.69 [95% CI 0.68-0.71]. The single-lead models also discriminated LVH etiologies well.

Conclusion

An artificial intelligence-enabled ECG model is favorable for detection and classification of LVH and outperforms clinical ECG-based rules.

Proteinuria, Body Mass Index, and the Risk of New-Onset Heart Failure: A Prospective Cohort Study in Northern China

Some studies have reported that body-mass index (BMI) and proteinuria are risk factors for heart failure (HF). However, the combined effect of BMI and proteinuria on HF is still unclear. We aimed to investigate the association of BMI and proteinuria levels with the risk of HF in a large community-based population. A total of 61, 113 individuals aged ≥18 years from the prospective Kailuan cohort (recruited during 2006-2007) without preexisting heart failure were included. Each participant was categorized into 4 groups according to BMI (< 25 kg/m2 or ≥ 25 kg/m2) and the urine dipstick test results (negative or positive). The primary outcome was HF. We performed multivariable Cox regression analyses to identify the association between BMI and proteinuria category and incident HF. Over a mean follow-up of 9.97±0.75 years, a total of 987 individuals developed incident HF, 1.62 per 1000 person-years. Compared to BMI < 25 kg/m2 and absence of proteinuria, the risk of HF was higher for BMI ≥ 25 kg/m2 and positive proteinuria (HR 2.630, 95% CI 1.982-3.490, P < 0.0001) (P for trend < 0.0001). Degree of proteinuria in participants was associated with a significantly higher rate of incident HF in dose dependent manner. Compared to consistently negative proteinuria, the risk of HF increased by 75.0% (HR 1.750, 95% CI 1.368-2.239, P < 0.0001) and 127.0% (HR 2.270, 95% CI 1.540-3.347, P < 0.0001) in the proteinuria aggravated group and persistent positive group, respectively. Proteinuria combined with a high BMI level is associated with an increased risk for HF in the Chinese population. However, the mechanism is unknown and awaits further study.

Serial blood pressure measurements, left ventricular remodelling and cardiovascular outcomes

BACKGROUND

Hypertension is a risk factor for the development of cardiovascular disease. Whether serial blood pressure (BP) measurements are more closely associated with subclinical left ventricular (LV) remodelling and better predict risk of cardiovascular events over individual BP measurements are not known.

METHODS

We assessed systolic BP, diastolic BP and pulse pressure at several time points during adulthood in 1333 women and 1211 men participating in the Akershus Cardiac Examination 1950 Study. We defined serial BP measurements as the sum of averaged BPs from adjacent consecutive visits indexed to total exposure time between measurements. We assessed the associations between serial and individual BP measurements and (1) LV structure, function and volumes and (2) incident myocardial infarction, ischemic stroke, heart failure and cardiovascular death.

RESULTS

All indices of higher serial BP measurements were associated with increased indexed LV mass, and the associations were stronger than those of individual BP measurements. Serial diastolic BP pressure was strongly and inversely associated with LV systolic function, while higher serial systolic BP was primarily associated with higher LV volumes. Both serial systolic (incidence rate ratio [IRR] 1.10, 95% CI 1.03 to 1.17) and diastolic BPs (IRR 1.14, 95% CI 1.02 to 1.27) were associated with increased incidence of clinical events.

CONCLUSION

In healthy community dwellers without established cardiovascular disease, different serial BP indices associate strongly with LV remodelling and cardiovascular outcomes. Whether the use of serial BP indices for guiding treatment is superior to individual measurements should be explored in additional prospective studies.

Pre-diagnostic predictors of mortality in patients with heart failure: The multi-ethnic study of atherosclerosis

Background

There are multiple predictive factors for cardiovascular (CV) mortality measured at, or after heart failure (HF) diagnosis. However, the predictive role of long-term exposure to these predictors prior to HF diagnosis is unknown.

Objectives

We aim to identify predictive factors of CV mortality in participants with HF, using cumulative exposure to risk factors before HF development.

Methods

Participants of Multi-Ethnic Study of Atherosclerosis (MESA) with incident HF were included. We used stepwise Akaike Information Criterion to select CV mortality predictors among clinical, biochemical, and imaging markers collected prior to HF. Using the AUC of B-spline-corrected curves, we estimated cumulative exposure to predictive factors from baseline to the last exam before HF. The prognostic performance for CV mortality after HF was evaluated using competing risk regression with non-CV mortality as the competing risk.

Results

Overall, 375 participants had new HF events (42.9% female, mean age: 74). Over an average follow-up of 4.7 years, there was no difference in the hazard of CV death for HF with reduced versus preserved ejection fraction (HR = 1.27, p = 0.23). The selected predictors of CV mortality in models with the least prediction error were age, cardiac arrest, myocardial infarction, and diabetes, QRS duration, HDL, cumulative exposure to total cholesterol and glucose, NT-proBNP, left ventricular mass, and statin use. The AUC of the models were 0.72 when including the latest exposure to predictive factors and 0.79 when including cumulative prior exposure to predictive factors (p = 0.20).

Conclusion

In HF patients, besides age and diagnosed diabetes or CVD, prior lipid profile, NT-proBNP, LV mass, and QRS duration available at the diagnosis time strongly predict CV mortality. Implementing cumulative exposure to cholesterol and glucose, instead of latest measures, improves predictive accuracy for HF mortality, though not reaching statistical significance.

Nonalcoholic Fatty Liver Disease Is Related to Abnormal Corrected QT Interval and Left Ventricular Hypertrophy in Chinese Male Steelworkers

OBJECTIVES

Nonalcoholic fatty liver disease (NAFLD) has been associated with an increased risks of corrected QT (QTc) prolongation and left ventricular hypertrophy (LVH), both of which are associated with the development of cardiovascular disease. Rotating night shift work and a higher risk of incident NAFLD have been reported in male steelworkers. This study aimed to investigate the association of the severity of NAFLD with a prolonged QTc interval and LVH in a large cohort of Chinese male steelworkers.

METHODS

We examined baseline data of 2998 male steel workers aged 26 to 71 years at two plants. All workers at both plants received regular health assessments, including 12-lead ECG and echocardiography. Abdominal ultrasonography was performed to evaluate the severity of NAFLD. QTc prolongation was defined as follows: normal ≤ 430 ms, borderline 431-450 ms, and abnormal ≥ 451 ms. LVH was defined as a left ventricular mass index (LVMI) >131 g/m2. Associations of NAFLD with an abnormal QTc interval and LVH were examined using univariate and multivariate analyses.

RESULTS

The QTc interval and the LVMI were significantly correlated with the NAFLD fibrosis score, and the severity of NAFLD was correlated with an abnormal QTc interval and LVH (p for trend < 0.05). Multivariate analysis showed that in comparison to the workers without NAFLD, the odds ratios of having an abnormal QTc interval and LVH were 2.54 (95% CI: 1.22-5.39, p = 0.013) times and 2.23 (95% CI: 1.02-5.01, p = 0.044) times higher in the workers with moderate/severe NAFLD.

CONCLUSIONS

NAFLD may be closely associated with the risks of an abnormal QTc interval and LVH, suggesting that regular electrocardiogram and echocardiogram monitoring could be used to evaluate the risk of arrhythmia and LVH in male steelworkers with NAFLD.

In situ diagnosis and simultaneous treatment of cardiac diseases using a single-device platform

The in situ diagnosis of cardiac activities with simultaneous therapeutic electrical stimulation of the heart is key to preventing cardiac arrhythmia. Here, we present an unconventional single-device platform that enables in situ monitoring even in a wet condition and control of beating heart motions without interferences to the recording signal. This platform consists of the active-matrix array of pressure-sensitive transistors for detecting cardiac beatings, biocompatible, low-impedance electrodes for cardiac stimulations, and an alginate-based hydrogel adhesive for attaching this platform conformally to the epicardium. In contrast to conventional electrophysiological sensing using electrodes, the pressure-sensitive transistors measured mechanophysiological characteristics by monitoring the spatiotemporal distributions of cardiac pressures during heart beating motions. In vivo tests show mechanophysiological readings having good correlation with electrocardiography and negligible interference with the electrical artifacts caused during cardiac stimulations. This platform can therapeutically synchronize the rhythm of abnormal heartbeats through efficient pacing of cardiac arrhythmia.

miR-21 upregulation exacerbates pressure overload-induced cardiac hypertrophy in aged hearts

Young and aging hearts undergo different remodeling post pressure overload, but the regulator that determines responses to pressure overload at different ages remains unknown. With an angiotensin II (Ang II)-induced hypertensive model, miR-21 knockout mice (miR-21^−/−) were observed regarding the effects of miR-21 on hypertension-induced cardiac remodeling in young (12 week-old) and old (50 week-old) mice. Although the aged heart represented a more significant hypertrophy and was associated with a higher expression of miR-21, Ang II-induced cardiac hypertrophy was attenuated in miR-21^−/− mice. Upon results of cardiac-specific arrays in miR-21-overexpressing cardiomyocytes, we found a significant downregulation of S100a8. In both in vitro and in vivo models, miR-21/S100a8/NF-κB/NFAT pathway was observed to be associated with pressure overload-induced hypertrophic remodeling in aged hearts. To further investigate whether circulating miR-21 could be a biomarker reflecting the aged associated cardiac remodeling, we prospectively collected clinical and echocardiographic information of patients at young (<65 y/o) and old ages (≥65 y/o) with and without hypertension. Among 108 patients, aged subjects presented with a significantly higher expression of circulating miR-21, which was positively correlated with left ventricular wall thickness. Collectively, miR-21 was associated with a prominently hypertrophic response in aged hearts under pressure overload. Further studies should focus on therapeutic potentials of miR-21.

Clinical Phenotypes of Heart Failure across the spectrum of Ejection Fraction: A Cluster Analysis

INTRODUCTION

Heart failure (HF), and especially HF with preserved ejection fraction (HFpEF), remains a challenging condition to define. The heterogenous nature of this population may be related to a variety of underlying etiologies interacting myocardial dysfunction.

METHOD

Alberta HEART study was a prospective, observational cohort that enrolled participants along the spectrum of heart failure including: healthy controls, people at risk of HF, and patients with HF and preserved (HFpEF) or reduced ejection fraction (HFrEF). We aimed to explore phenotypes of patients with HF and at-risk of developing HF. Utilising 27 detailed clinical, echocardiographic and biomarker variables, latent class analysis with and without multiple imputation was undertaken to identify distinct clinical phenotypes.

RESULTS

Of 621 participants, 191 (30.8%) and 169 (27.2%) were adjudicated by cardiologists to have HFpEF and HFrEF respectively. In the overall cohort, latent class analysis identified four distinct phenotypes. Phenotype A (n=152, 24.5%) was a healthy and low risk group. Phenotype B (n=129, 20.8%) demonstrated increased left ventricular mass and end-diastolic volumes, with elevated natriuretic peptides and clinical features of congestion. Phenotype C (n=128, 20.6%) was primarily characterised by obesity (80%) and normal indexed cardiac chamber sizes, low natriuretic peptide levels and minimal features of congestion. Phenotype D (n=212, 34.1%) consisted of elderly patients with clinical features of congestions. Phenotypes B and D demonstrated the highest risk of mortality and hospitalization over a median follow-up of 3.7 years.

CONCLUSION

Phenotypes with congestive features demonstrated increased risk profiles. Heart failure is a heterogenous classification which requires further work to appropriately categorise patients based on the underlying etiology or mechanism of impairment.

Diabesity in Elderly Cardiovascular Disease Patients: Mechanisms and Regulators

Cardiovascular disease (CVD) is the leading cause of death in the world. In 2019, 550 million people were suffering from CVD and 18 million of them died as a result. Most of them had associated risk factors such as high fasting glucose, which caused 134 million deaths, and obesity, which accounted for 5.02 million deaths. Diabesity, a combination of type 2 diabetes and obesity, contributes to cardiac, metabolic, inflammation and neurohumoral changes that determine cardiac dysfunction (diabesity-related cardiomyopathy). Epicardial adipose tissue (EAT) is distributed around the myocardium, promoting myocardial inflammation and fibrosis, and is associated with an increased risk of heart failure, particularly with preserved systolic function, atrial fibrillation and coronary atherosclerosis. In fact, several hypoglycaemic drugs have demonstrated a volume reduction of EAT and effects on its metabolic and inflammation profile. However, it is necessary to improve knowledge of the diabesity pathophysiologic mechanisms involved in the development and progression of cardiovascular diseases for comprehensive patient management including drugs to optimize glucometabolic control. This review presents the mechanisms of diabesity associated with cardiovascular disease and their therapeutic implications.

Differences in Regulation of Cortisol Secretion Contribute to Left Ventricular Abnormalities in Patients With Essential Hypertension

BACKGROUND

Left ventricular (LV) abnormalities were reported in patients with overt and subclinical Cushing syndrome. The aim of this study was to investigate the relationships of daily plasma cortisol profile and cortisol response to an overnight suppression test with cardiac changes in patients with hypertension.

METHODS

In a cross-sectional study, we included 136 nondiabetic, patients with essential hypertension who were free of cardiovascular and renal complications. Plasma cortisol was measured at 8 am, 3 pm, and 12 am and at 8 am after overnight suppression with 1 mg dexamethasone (dexamethasone suppression test [DST]). Echocardiography was performed with standard B-mode and tissue-Doppler imaging.

RESULTS

LV hypertrophy was present in 30% and LV diastolic dysfunction in 51% of patients who were older and had significantly higher body mass index, systolic blood pressure, duration of hypertension, and 12 am and DST cortisol. LV mass index and relative wall thickness increased progressively across tertiles of DST cortisol, together with progressive worsening of diastolic function. LV mass index was directly related to age, systolic blood pressure, duration of hypertension, and 12 am and DST cortisol, and inversely to creatinine clearance. Multivariate regression analysis showed independent correlation of LV mass index with body mass index, systolic blood pressure, and 12 am and DST cortisol. Logistic regression showed that DST cortisol independently predicted LV hypertrophy.

CONCLUSIONS

Midnight and DST plasma cortisol levels are independent determinants of LV mass and geometry in patients with essential hypertension suggesting that even minor changes in regulation of cortisol secretion could contribute to cardiac abnormalities in these patients.

Atrial fibrillation in heart failure patients: An update on renin-angiotensin-aldosterone system pathway blockade as a therapeutic and prevention target

Heart failure (HF) and atrial fibrillation (AF) are two cardiovascular (CV) entities that affect millions of individuals worldwide and their prevalence is translated into a significant impact on health care systems. The common pathophysiological pathways that these two share have created an important clinical interrelation, as the coexistence of HF and AF is associated with worse prognosis and treatment challenges. Renin-angiotensin-aldosterone system (RAAS), a critical mechanism in blood pressure (BP) control, was proved to be involved in the pathogenesis of both conditions contributing to their further coexistence. Successful control of BP is of great importance to the management of HF, crucial for the prevention of arrhythmiogenic substrates, while RAAS antagonists may possibly affect the development of new-onset AF as well. There are numerous studies that evaluated the effectiveness of RAAS blockade in AF/HF population and despite comparable or modest results, there is a well-established suggestion that RAAS blockers may contribute to a reduction of HF, CV events and recurrence of AF, along with their potential effective role in the new-onset AF prophylaxis. Angiotensin receptor blockers, according to the evidence, are more effective in that direction, followed by angiotensin converting enzyme inhibitors, whereas the data on aldosterone antagonists are not encouraging, yet do have the potential of significant CV disease modificators regardless of their effects on BP.

Epoxyeicosatrienoic acid: A potential therapeutic target of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) reduces the quality of life, costs substantial medical resources, and has a high mortality. However, we lack an effective therapy for HFpEF due to our limited knowledge of its mechanism. Therefore, it is crucial to explore novel therapeutics, such as those with endogenous protective roles, and seek new targeted therapies. Epoxyeicosatrienoic acids (EETs) are endogenous bioactive metabolites of arachidonic acids produced by cytochrome P450 (CYP) epoxygenases. EETs can function as endogenous cardioprotective factors with potent inhibitory roles in inflammation, endothelial dysfunction, cardiac remodeling, and fibrosis, which are the fundamental mechanisms of HFpEF. This suggests that EETs have the potential function to protect against HFpEF. Therefore, we present an overview of the ever-expanding world of EETs and how they might help alleviate the pathophysiology underlying HFpEF to provide new insights for research in this field.

Clinical Data, Chest Radiograph and Electrocardiography in the Screening for Left Ventricular Hypertrophy: The CAR2E2 Score

Left ventricular hypertrophy (LVH) is associated with adverse clinical outcomes and implicates clinical decision-making. The aim of our study was to assess the importance of different approaches in the screening for LVH. We included patients who underwent cardiac magnetic resonance (CMR) imaging and had available chest radiograph in medical documentation. Cardiothoracic ratio (CTR), transverse cardiac diameter (TCD), clinical and selected electrocardiographic (ECG)-LVH data, including the Peguero-Lo Presti criterion, were assessed. CMR−LVH was defined based on indexed left ventricular mass-to-body surface area. Receiver operating characteristics analyses showed that both the CTR and TCD (CTR: area under the curve: [AUC] = 0.857, p < 0.001; TCD: AUC = 0.788, p = 0.001) were predictors for CMR−LVH. However, analyses have shown that diagnoses made with TCD, but not CTR, were consistent with CMR−LVH. From the analyzed ECG−LVH criteria, the Peguero-Lo Presti criterion was the best predictor of LVH. The best sensitivity for screening for LVH was observed when the presence of heart failure, ≥40 years in age (each is assigned 1 point), increased TCD and positive Peguero-Lo Presti criterion (each is assigned 2 points) were combined (CAR2E2 score ≥ 3 points). CAR2E2 score may improve prediction of LVH compared to other approaches. Therefore, it may be useful in the screening for LVH in everyday clinical practice in patients with prevalent cardiovascular diseases.

Targeting Microtubules for the Treatment of Heart Disease

Heart disease remains the leading cause of morbidity and mortality worldwide. With the advancement of modern technology, the role(s) of microtubules in the pathogenesis of heart disease has become increasingly apparent, though currently there are limited treatments targeting microtubule-relevant mechanisms. Here, we review the functions of microtubules in the cardiovascular system and their specific adaptive and pathological phenotypes in cardiac disorders. We further explore the use of microtubule-targeting drugs and highlight promising druggable therapeutic targets for the future treatment of heart diseases.

Loss of talin in cardiac fibroblasts results in augmented ventricular cardiomyocyte hypertrophy in response to pressure overload

Pressure overload of the heart is characterized by concentric hypertrophy and interstitial fibrosis. Cardiac fibroblasts (CFs) in the ventricular wall become activated during injury and synthesize and compact the extracellular matrix, which causes interstitial fibrosis and stiffening of the ventricular heart walls. Talin1 (Tln1) and Talin2 (Tln2) are mechanosensitive proteins that participate in focal adhesion transmission of signals from the extracellular environment to the actin cytoskeleton of CFs. The aim of the present study was to determine whether the removal of Tln1 and Tln2 from CFs would reduce interstitial fibrosis and cardiac hypertrophy. Twelve-week-old male and female Tln2-null (Tln2-/-) and Tln2-null, CF-specific Tln1 knockout (Tln2-/-;Tln1CF-/-) mice were given angiotensin-II (ANG II) (1.5 mg/kg/day) or saline through osmotic pumps for 8 wk. Cardiomyocyte area and measures of heart thickness were increased in the male ANG II-infused Tln2-/-;Tln1CF-/- mice, whereas there was no increase in interstitial fibrosis. Systolic blood pressure was increased in the female Tln2-/-;Tln1CF-/- mice after ANG II infusion compared with the Tln2-/- mice. However, there was no increase in cardiac hypertrophy in the Tln2-/-;Tln1CF-/- mice, which was seen in the Tln2-/- mice. Collectively, these data indicate that in male mice, the absence of Tln1 and Tln2 in CFs leads to cardiomyocyte hypertrophy in response to ANG II, whereas it results in a hypertrophy-resistant phenotype in female mice. These findings have important implications for the role of mechanosensitive proteins in CFs and their impact on cardiomyocyte function in the pathogenesis of hypertension and cardiac hypertrophy.NEW & NOTEWORTHY The role of talins has been previously studied in cardiomyocytes; however, these mechanotransductive proteins that are members of the focal adhesion complex have not been examined in cardiac fibroblasts previously. We hypothesized that loss of talins in cardiac fibroblasts would reduce interstitial fibrosis in the heart with a pressure overload model. However, we found that although loss of talins did not alter fibrosis, it did result in cardiomyocyte and ventricular hypertrophy.

Mitochondrial Sirtuin-3 (SIRT3) Prevents Doxorubicin-Induced Dilated Cardiomyopathy by Modulating Protein Acetylation and Oxidative Stress

BACKGROUND

High doses of doxorubicin put cancer patients at risk for developing dilated cardiomyopathy. Previously, we showed that doxorubicin treatment decreases SIRT3 (sirtuin 3), the main mitochondrial deacetylase and increases protein acetylation in rat cardiomyocytes. Here, we hypothesize that SIRT3 expression can attenuate doxorubicin induced dilated cardiomyopathy in vivo by preventing the acetylation of mitochondrial proteins.

METHODS

Nontransgenic, M3-SIRT3 (truncated SIRT3; short isoform), and M1-SIRT3 (full-length SIRT3; mitochondrial localized) transgenic mice were treated with doxorubicin for 4 weeks (8 mg/kg body weight per week). Echocardiography was performed to assess cardiac structure and function and validated by immunohistochemistry and immunofluorescence (n=4-10). Mass spectrometry was performed on cardiac mitochondrial peptides in saline (n=6) and doxorubicin (n=5) treated hearts. Validation was performed in doxorubicin treated primary rat and human induced stem cell derived cardiomyocytes transduced with adenoviruses for M3-SIRT3 and M1-SIRT3 and deacetylase deficient mutants (n=4-10).

RESULTS

Echocardiography revealed that M3-SIRT3 transgenic mice were partially resistant to doxorubicin induced changes to cardiac structure and function whereas M1-SIRT3 expression prevented cardiac remodeling and dysfunction. In doxorubicin hearts, 37 unique acetylation sites on mitochondrial proteins were altered. Pathway analysis revealed these proteins are involved in energy production, fatty acid metabolism, and oxidative stress resistance. Increased M1-SIRT3 expression in primary rat and human cardiomyocytes attenuated doxorubicin-induced superoxide formation, whereas deacetylase deficient mutants were unable to prevent oxidative stress.

CONCLUSIONS

Doxorubicin reduced SIRT3 expression and markedly affected the cardiac mitochondrial acetylome. Increased M1-SIRT3 expression in vivo prevented doxorubicin-induced cardiac dysfunction, suggesting that SIRT3 could be a potential therapeutic target for mitigating doxorubicin-induced dilated cardiomyopathy.

O-ring-induced transverse aortic constriction (OTAC) is a new simple method to develop cardiac hypertrophy and heart failure in mice

Suture-based transverse aortic constriction (TAC) in mice is one of the most frequently used experimental models for cardiac pressure overload-induced heart failure. However, the incidence of heart failure in the conventional TAC depends on the operator's skill. To optimize and simplify this method, we proposed O-ring-induced transverse aortic constriction (OTAC) in mice. C57BL/6J mice were subjected to OTAC, in which an o-ring was applied to the transverse aorta (between the brachiocephalic artery and the left common carotid artery) and tied with a triple knot. We used different inner diameters of o-rings were 0.50 and 0.45 mm. Pressure overload by OTAC promoted left ventricular (LV) hypertrophy. OTAC also increased lung weight, indicating severe pulmonary congestion. Echocardiographic findings revealed that both OTAC groups developed LV hypertrophy within one week after the procedure and gradually reduced LV fractional shortening. In addition, significant elevations in gene expression related to heart failure, LV hypertrophy, and LV fibrosis were observed in the LV of OTAC mice. We demonstrated the OTAC method, which is a simple and effective cardiac pressure overload method in mice. This method will efficiently help us understand heart failure (HF) mechanisms with reduced LV ejection fraction (HFrEF) and cardiac hypertrophy.

Lp-PLA2 inhibition prevents Ang II-induced cardiac inflammation and fibrosis by blocking macrophage NLRP3 inflammasome activation

Macrophage-mediated inflammation plays an important role in hypertensive cardiac remodeling, whereas effective pharmacological treatments targeting cardiac inflammation remain unclear. Lipoprotein-associated phospholipase A2 (Lp-PLA2) contributes to vascular inflammation-related diseases by mediating macrophage migration and activation. Darapladib, the most advanced Lp-PLA2 inhibitor, has been evaluated in phase III trials in atherosclerosis patients. However, the role of darapladib in inhibiting hypertensive cardiac fibrosis remains unknown. Using a murine angiotensin II (Ang II) infusion-induced hypertension model, we found that Pla2g7 (the gene of Lp-PLA2) was the only upregulated PLA2 gene detected in hypertensive cardiac tissue, and it was primarily localized in heart-infiltrating macrophages. As expected, darapladib significantly prevented Ang II-induced cardiac fibrosis, ventricular hypertrophy, and cardiac dysfunction, with potent abatement of macrophage infiltration and inflammatory response. RNA sequencing revealed that darapladib strongly downregulated the expression of genes and signaling pathways related to inflammation, extracellular matrix, and proliferation. Moreover, darapladib substantially reduced the Ang II infusion-induced expression of nucleotide-binding oligomerization domain-like receptor with pyrin domain 3 (NLRP3) and interleukin (IL)-1β and markedly attenuated caspase-1 activation in cardiac tissues. Furthermore, darapladib ameliorated Ang II-stimulated macrophage migration and IL-1β secretion in macrophages by blocking NLRP3 inflammasome activation. Darapladib also effectively blocked macrophage-mediated transformation of fibroblasts into myofibroblasts by inhibiting the activation of the NLRP3 inflammasome in macrophages. Overall, our study identifies a novel anti-inflammatory and anti-cardiac fibrosis role of darapladib in Lp-PLA2 inhibition, elucidating the protective effects of suppressing NLRP3 inflammasome activation. Lp-PLA2 inhibition by darapladib represents a novel therapeutic strategy for hypertensive cardiac damage treatment.

The Mechanism Actions of Astragaloside IV Prevents the Progression of Hypertensive Heart Disease Based on Network Pharmacology and Experimental Pharmacology

Astragaloside IV (AS-IV) has been used to treat cardiovascular disease. However, whether AS-IV exerts a protective effect against hypertensive heart disease has not been investigated. This study aimed to investigate the antihypertensive and cardioprotective effects of AS-IV on L-NAME-induced hypertensive rats via network pharmacology and experimental pharmacology. The network pharmacology and bioinformatics analyses were performed to obtain the potential targets of AS-IV and hypertensive heart disease. The rat hypertension model was established by administrated 50 mg/kg/day of L-NAME for 5 weeks. Meanwhile, hypertension rats were intragastrically administrated with vehicle or AS-IV or fosinopril for 5 weeks. Cardiovascular parameters (systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rates, and body weight), cardiac function parameters (LVEDd, LVEDs, and fractional shortening), cardiac marker enzymes (creatine kinase, CK-MB, and lactate dehydrogenase), cardiac hypertrophy markers (atrial natriuretic peptide and brain natriuretic peptide), endothelial function biomarkers (nitric oxide and eNOS), inflammation biomarkers (IL-6 and TNF-α) and oxidative stress biomarkers (SOD, MDA, and GSH) were measured and cardiac tissue histology performed. Network pharmacological analysis screened the top 20 key genes in the treatment of hypertensive heart disease treated with AS-IV. Besides, AS-IV exerted a beneficial effect on cardiovascular and cardiac function parameters. Moreover, AS-IV alleviated cardiac hypertrophy via down-regulating the expression of ANP and BNP and improved histopathology changes of cardiac tissue. AS-IV improved endothelial function via the up-regulation of eNOS expression, alleviated oxidative stress via increasing antioxidant enzymes activities, and inhibited cardiac inflammation via down-regulating IL-6 and TNF-α expression. Our findings suggested that AS-IV is a potential therapeutic drug to improve L-NAME-induced hypertensive heart disease partly mediated via modulation of eNOS and oxidative stress.

Association Between the Angiotensin II/Angiotensin (1-7) Imbalance and Left Ventricular Hypertrophy in Patients with Heart Failure

Introduction: Angiotensin II (AngII) and angiotensin-(1-7) [Ang-(1-7)] are key components of the renin angiotensin system (RAS). They exhibit counter-regulatory effects in the systemic circulation, as well as in tissues important for cardiovascular regulation.

Aim: To investigate the association between the AngII/Ang-(1-7) balance and left ventricular hypertrophy (LVH) in patients with heart failure and mid-range ejection fraction (HFmrEF).

Material and methods: 56 patients with HFmrEF were included, with a mean age of 65.62 ± 9.69 years and 22 age- and sex-matched healthy subjects, their mean age - 56.4 ± 5.53 years. The patients were divided in two subgroups: subjects with left ventricular hypertrophy (n = 32); (HFmrEF+LVH) and subjects without left ventricular hypertrophy (n = 24); (HFmrEFLVH). AngII and Ang-(1-7) levels were measured with an ELISA kit.

Results: Patients with HFmrEF+LVH showed significantly higher levels of AngII: 8.53 pg/mL (1.47 ÷ 13.0) than HFmrEF-LVH – 1.33 pg/mL (0.47 ÷ 6.93) and healthy controls – 1.53 pg/mL (0.27 ÷ 5.21); (KW = 3.48; p = 0.04). There was no significant difference between Ang-(1-7) levels in all patients compared to controls (p > 0.05). AngII/Ang-(1-7) ratio was significantly higher in all patients than controls: 3.81 (2.03 ÷ 6.66) vs. 1.5 (0.93 ÷ 2.06) (KW = 18.68; p < 0.001). Patients with HFmrEF+LVH showed statistically higher AngII/Ang-(1-7) ratio compared with controls (4.7 vs. 1.5). Moreover, subjects with LVH showed the highest AngII/Ang-(1-7) ratio among all particpants in the study. The AngII/Ang-(1-7) ratio correlated with LVH (r = -0.39; p = 0.03), DBP (r = 0.25; p = 0.04), HDL (r = 0.33; p = 0.01), SBP (r = 0.34; p = 0.01).

Conclusion: Our study showed an association between AngII/Ang-(1-7) ratio, blood pressure and LVH. The imbalance between Ang-II and Ang-(1-7) could contribute to the mechanisms determining LVH in HFmrEF. Further studies are warranted to clarify whether evaluation of serum Ang-II/Ang-(1-7) ratio could predict LVH development in patients with HFmrEF.

Between Inflammation and Autophagy: The Role of Leptin-Adiponectin Axis in Cardiac Remodeling

Cardiac remodeling is the process by which the heart adapts to stressful stimuli, such as hypertension and ischemia/reperfusion; it ultimately leads to heart failure upon long-term exposure. Autophagy, a cellular catabolic process that was originally considered as a mechanism of cell death in response to detrimental stimuli, is thought to be one of the main mechanisms that controls cardiac remodeling and induces heart failure. Dysregulation of the adipokines leptin and adiponectin, which plays essential roles in lipid and glucose metabolism, and in the pathophysiology of the neuroendocrine and cardiovascular systems, has been shown to affect the autophagic response in the heart and to contribute to accelerate cardiac remodeling. The obesity-associated protein leptin is a pro-inflammatory, tumor-promoting adipocytokine whose elevated levels in obesity are associated with acute cardiovascular events, and obesity-related hypertension. Adiponectin exerts anti-inflammatory and anti-tumor effects, and its reduced levels in obesity correlate with the pathogenesis of obesity-associated cardiovascular diseases. Leptin- and adiponectin-induced changes in autophagic flux have been linked to cardiac remodeling and heart failure. In this review, we describe the different molecular mechanisms of hyperleptinemia- and hypoadiponectinemia-mediated pathogenesis of cardiac remodeling and the involvement of autophagy in this process. A better understanding of the roles of leptin, adiponectin, and autophagy in cardiac functions and remodeling, and the exact signal transduction pathways by which they contribute to cardiac diseases may well lead to discovery of new therapeutic agents for the treatment of cardiovascular remodeling.

Correlation of Coronary Artery Disease and Left Ventricular Hypertrophy

Ischemic heart disease (IHD) is the leading cause of death worldwide, and it is defined as an imbalance between myocardial oxygen supply and demand. Coronary artery disease (CAD) and left ventricular hypertrophy (LVH) are two common causes of IHD that independently result in myocardial ischemia. CAD decreases myocardial blood and oxygen supply whereas LVH increases myocardial oxygen demand. The coexistence of both CAD and LVH results in a significant increase in oxygen demand while simultaneously lowering oxygen supply.

Since hypertension is a shared predisposing condition for both CAD and LVH, the left ventricular (LV) mass on noninvasive echocardiography can reflect on the severity of coronary artery stenosis. In clinical practice, it can help physicians decide whether to perform invasive cardiac catheterization to visualize the extent of the coronary block. Although, both CAD and LVH are directly proportional to mortality risk, the addition of eccentric LVH can further increase morbidity and mortality due to myocardial infarction. Therefore, the latest management of both the acute and chronic phases of CAD places an increased emphasis on controlling the predisposing factors to prevent or reverse LVH. For example, angiotensin-converting enzyme inhibitors and diuretics reduce LV mass by lowering the cardiac preload and afterload. This article aims to investigate the deleterious effects of the collaboration between CAD and LVH, establish a causal relationship, and explore the new prevention and management strategies.

Decorin Induces Cardiac Hypertrophy by Regulating the CaMKII/MEF-2 Signaling Pathway In Vivo

OBJECTIVE

Cardiac hypertrophy is an adaptive reaction of the heart against cardiac overloading, but continuous cardiac hypertrophy can lead to cardiac remodeling and heart failure. Cardiac hypertrophy is mostly considered reversible, and recent studies have indicated that decorin not only prevents cardiac fibrosis associated with hypertension, but also achieves therapeutic effects by blocking fibrosis-related signaling pathways. However, the mechanism of action of decorin remains unknown and unconfirmed.

METHODS

We determined the degree of myocardial hypertrophy by measuring the ratios of the heart weight/body weight and left ventricular weight/body weight, histological analysis and immunohistochemistry. Western blotting was performed to detect the expression levels of CaMKII, p-CaMKII and MEF-2 in the heart.

RESULTS

Our results confirmed that decorin can regulate the CaMKII/MEF-2 signaling pathway, with inhibition thereof being similar to that of decorin in reducing cardiac hypertrophy.

CONCLUSION

Taken together, the results of the present study showed that decorin induced cardiac hypertrophy by regulating the CaMKII/MEF-2 signaling pathway in vivo, revealing a new therapeutic approach for the prevention of cardiac hypertrophy.

Pharmacotherapy for hypertension-induced left ventricular hypertrophy

BACKGROUND

Hypertension is the leading preventable risk factor for cardiovascular disease and premature death worldwide. One of the clinical effects of hypertension is left ventricular hypertrophy (LVH), a process of cardiac remodelling. It is estimated that over 30% of people with hypertension also suffer from LVH, although the prevalence rates vary according to the LVH diagnostic criteria. Severity of LVH is associated with a higher prevalence of cardiovascular disease and an increased risk of death. The role of antihypertensives in the regression of left ventricular mass has been extensively studied. However, uncertainty exists regarding the role of antihypertensive therapy compared to placebo in the morbidity and mortality of individuals with hypertension-induced LVH.

OBJECTIVES

To assess the effect of antihypertensive pharmacotherapy compared to placebo or no treatment on morbidity and mortality of adults with hypertension-induced LVH.

SEARCH METHODS

Cochrane Hypertension's Information Specialist searched the following databases for studies: Cochrane Hypertension Specialised Register (to 26 September 2020), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library; 2020, Issue 9), Ovid MEDLINE (1946 to 22 September 2020), and Ovid Embase (1974 to 22 September 2020). We searched the World Health Organization International Clinical Trials Registry Platform and the ClinicalTrials.gov for ongoing trials. We also searched Epistemonikos (to 19 February 2021), LILACS BIREME (to 19 February 2021), and Clarivate Web of Science (to 26 February 2021), and contacted authors and funders of the identified trials to obtain additional information and individual participant data. There were no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) with at least 12 months' follow-up comparing antihypertensive pharmacological therapy (monotherapy or in combination) with placebo or no treatment in adults (18 years of age or older) with hypertension-induced LVH were eligible for inclusion. The trials must have analysed at least one primary outcome (all-cause mortality, cardiovascular events, or total serious adverse events) to be considered for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors screened the search results, with any disagreements resolved by consensus amongst all review authors. Two review authors carried out the data extraction and analyses. We assessed risk of bias of the included studies following Cochrane methodology. We used the GRADE approach to assess the certainty of the body of evidence.

MAIN RESULTS

We included three multicentre RCTs. We selected 930 participants from the included studies for the analyses, with a mean follow-up of 3.8 years (range 3.5 to 4.3 years). All of the included trials performed an intention-to-treat analysis. We obtained evidence for the review by identifying the population of interest from the trials' total samples. None of the trials provided information on the cause of LVH. The intervention varied amongst the included trials: hydrochlorothiazide plus triamterene with the possibility of adding alpha methyldopa, spironolactone, or olmesartan. Placebo was administered to participants in the control arm in two trials, whereas participants in the control arm of the remaining trial did not receive any add-on treatment. The evidence is very uncertain regarding the effect of additional antihypertensive pharmacological therapy compared to placebo or no treatment on mortality (14.3% intervention versus 13.6% control; risk ratio (RR) 1.02, 95% confidence interval (CI) 0.74 to 1.40; 3 studies; 930 participants; very low-certainty evidence); cardiovascular events (12.6% intervention versus 11.5% control; RR 1.09, 95% CI 0.77 to 1.55; 3 studies; 930 participants; very low-certainty evidence); and hospitalisation for heart failure (10.7% intervention versus 12.5% control; RR 0.82, 95% CI 0.57 to 1.17; 2 studies; 915 participants; very low-certainty evidence). Although both arms yielded similar results for total serious adverse events (48.9% intervention versus 48.1% control; RR 1.02, 95% CI 0.89 to 1.16; 3 studies; 930 participants; very low-certainty evidence) and total adverse events (68.3% intervention versus 67.2% control; RR 1.07, 95% CI 0.86 to 1.34; 2 studies; 915 participants), the incidence of withdrawal due to adverse events may be significantly higher with antihypertensive drug therapy (15.2% intervention versus 4.9% control; RR 3.09, 95% CI 1.69 to 5.66; 1 study; 522 participants; very low-certainty evidence). Sensitivity analyses limited to blinded trials, trials with low risk of bias in core domains, and trials with no funding from the pharmaceutical industry did not change the results of the main analyses. Limited evidence on the change in left ventricular mass index prevented us from drawing any firm conclusions.

AUTHORS' CONCLUSIONS

We are uncertain about the effects of adding additional antihypertensive drug therapy on the morbidity and mortality of participants with LVH and hypertension compared to placebo. Although the incidence of serious adverse events was similar between study arms, additional antihypertensive therapy may be associated with more withdrawals due to adverse events. Limited and low-certainty evidence requires that caution be used when interpreting the findings. High-quality clinical trials addressing the effect of antihypertensives on clinically relevant variables and carried out specifically in individuals with hypertension-induced LVH are warranted.

Multi-omic Analysis of Non-human Primate Heart after Partial-body Radiation with Minimal Bone Marrow Sparing

ABSTRACT

High-dose radiation exposure results in hematopoietic and gastrointestinal acute radiation syndromes followed by delayed effects of acute radiation exposure, which encompasses multiple organs, including heart, kidney, and lung. Here we sought to further characterize the natural history of radiation-induced heart injury via determination of differential protein and metabolite expression in the heart. We quantitatively profiled the proteome and metabolome of left and right ventricle from non-human primates following 12 Gy partial body irradiation with 2.5% bone marrow sparing over a time period of 3 wk. Global proteome profiling identified more than 2,200 unique proteins, with 220 and 286 in the left and right ventricles, respectively, showing significant responses across at least three time points compared to baseline levels. High-throughput targeted metabolomics analyzed a total of 229 metabolites and metabolite combinations, with 18 and 22 in the left and right ventricles, respectively, showing significant responses compared to baseline levels. Bioinformatic analysis performed on metabolomic and proteomic data revealed pathways related to inflammation, energy metabolism, and myocardial remodeling were dysregulated. Additionally, we observed dysregulation of the retinoid homeostasis pathway, including significant post-radiation decreases in retinoic acid, an active metabolite of vitamin A. Significant differences between left and right ventricles in the pathology of radiation-induced injury were identified. This multi-omic study characterizes the natural history and molecular mechanisms of radiation-induced heart injury in NHP exposed to PBI with minimal bone marrow sparing.

Therapeutic potential and recent advances on targeting mitochondrial dynamics in cardiac hypertrophy: A concise review

Pathological cardiac hypertrophy begins as an adaptive response to increased workload; however, sustained hemodynamic stress will lead it to maladaptation and eventually cardiac failure. Mitochondria, being the powerhouse of the cells, can regulate cardiac hypertrophy in both adaptive and maladaptive phases; they are dynamic organelles that can adjust their number, size, and shape through a process called mitochondrial dynamics. Recently, several studies indicate that promoting mitochondrial fusion along with preventing mitochondrial fission could improve cardiac function during cardiac hypertrophy and avert its progression toward heart failure. However, some studies also indicate that either hyperfusion or hypo-fission could induce apoptosis and cardiac dysfunction. In this review, we summarize the recent knowledge regarding the effects of mitochondrial dynamics on the development and progression of cardiac hypertrophy with particular emphasis on the regulatory role of mitochondrial dynamics proteins through the genetic, epigenetic, and post-translational mechanisms, followed by discussing the novel therapeutic strategies targeting mitochondrial dynamic pathways.

Performance of a novel ECG criterion for improving detection of left ventricular hypertrophy: a cross-sectional study in a general Chinese population

OBJECTIVES

The sensitivity of ECG for detecting left ventricular hypertrophy (LVH) is low. The aim of this study was to explore a better ECG criterion for screening LVH in a large general Chinese population.

DESIGN

Case-control study.

SETTING

China Medical University in Shenyang, China.

PARTICIPANTS

All permanent residents in Dawa, Zhangwu and Liaoyang aged 35 years or older were invited. Participants with unqualified data, pacemaker rhythm, frequent premature ventricular beats, Wolff-Parkinson-White syndrome, complete bundle branch block, myocardial infarction or hypertrophic cardiomyopathy were excluded. A total of 10 360 subjects (4630 males) were recruited.

INTERVENTIONS

A novel ECG criterion (Northeast China Rural Cardiovascular Health Study (NCRCHS)) composed of different ratios of maximum R wave in lead V₅ or V₆ (R_V5/V6), S wave in lead V₃ (S_V3) and R wave in lead aVL (R_aVL) was proposed and validated using multiple linear regression. Receiver-operating characteristic curves were used to compare the NCRCHS criterion with traditional criteria for LVH detection.

RESULTS

An optimised model (15^*R_aVL+8^*S_V3+7^*R_V5/V6) was constructed (R² 0.192, p<0.001) with the cut-off values of 36.8 mV for males and 26.1 mV for females. The maximum area under the curve was obtained using the NCRCHS criterion (male 0.74, 95% CI 0.73 to 0.75; female 0.73, 95% CI 0.72 to 0.75), followed by Cornell voltage criterion, Sokolow-Lyon criterion, Peguero-Lo Presti criterion, multi-ethnic study of atherosclerosis (MESA)-specific criterion and Syst-Eur voltage criterion. Compared with the Cornell voltage criterion, the NCRCHS criterion had a significantly higher sensitivity for detecting LVH at the same level of specificity (p<0.05).

CONCLUSIONS

The NCRCHS criterion significantly improved sensitivity for LVH detection in a general Chinese population, with cut-off values of 36.8 and 26.1 mV for males and females, respectively. This criterion can detect LVH earlier and better and may prevent subsequent cardiovascular diseases.

Cardiovascular dysfunction risk in young adults with congenital adrenal hyperplasia caused by 21-hydroxylase enzyme deficiency

BACKGROUND

The association of congenital adrenal hyperplasia (CAH) caused by 21-hydroxylase enzyme (21OHase) deficiency, duration of treatment and dosage with cardiovascular dysfunction in young adults remains unclear. We aimed to evaluate myocardial function, vascular structures and epicardial fat thickness in young adults with CAH as a result of 21OHase deficiency. Correlations between the duration and dose of glucocorticoid therapy and cardiovascular parameters were analysed.

METHODS

This case-control study of young adults (18-31 years old) included 20 patients (5 men and 15 women) and 16 control subjects (8 men and 8 women). Echocardiographic analysis was performed using high-resolution ultrasound.

RESULTS

No ultrasonographic changes in any indices of myocardial function, vascular structures and epicardial fat thickness were found in patients, except for an impaired left ventricular end-diastolic diameter in female patients (28.1 ± 1.6 vs 26.0 ± 2.4 mm/m² , P = .021), compared with those in individuals in the control group. Nevertheless, the individual patient values were within the normal range. Multiple linear regression analysis in female patients demonstrated that an elevated daily dose of glucocorticoids correlated with increased indices of left ventricular posterior wall thickness (Partial r = 0.68, P = .007), left ventricular end-diastolic diameter (Partial r = 0.62, P = .017), aortic diameter (Partial r = 0.60, P = .022) and left carotid artery intima-media thickness (Partial r = 0.61, P = .021), independently of treatment duration.

CONCLUSION

No signs of cardiovascular dysfunction were observed in any patient. The daily dose of glucocorticoids may play a role in the mechanisms of some markers of cardiac hypertrophy, left ventricular and aortic dilation and subclinical atherosclerosis.

Epidemiological and clinical boundaries of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is highly prevalent and is associated with relevant morbidity and mortality. However, an evidence-based treatment is still absent. The heterogeneous definitions, differences in aetiology/pathophysiology, and diagnostic challenges of HFpEF made it difficult to define its epidemiological landmarks so far. Several large registries and observational studies have recently disclosed an increasing incidence/prevalence, as well as its prognostic significance. An accurate definition of HFpEF epidemiological boundaries and phenotypes is mandatory to develop novel effective and rational therapeutic approaches.

Piperlongumine attenuates angiotensin-II-induced cardiac hypertrophy and fibrosis by inhibiting Akt-FoxO1 signalling

BACKGROUND

Cardiac hypertrophy and fibrosis are closely related to cardiac dysfunction, especially diastolic dysfunction. Limited medications can be used to simultaneously delay cardiac hypertrophy and fibrosis in clinical practice. Piperlongumine (PLG) is an amide alkaloid extracted from Piper longum and has been shown to have multiple biological effects, including anticancer and antioxidant effects. However, the role of PLG in cardiac hypertrophy and fibrosis is not clear.

PURPOSE

The aim of this study was to reveal the role of PLG in cardiac hypertrophy and fibrosis and the associated mechanism.

METHODS

Cardiac hypertrophy and fibrosis were induced by angiotensin II (Ang II) in vivo and in vitro. The effect of PLG in vivo, in vitro and its mechanism were investigated by proliferation and apoptosis assays, western blot, real-time PCR, immunofluorescence, histochemistry, echocardiography, flow cytometry and chromatin immunoprecipitation.

RESULTS

Proliferation and apoptosis assays showed that 2.5 μM PLG slightly inhibited proliferation and did not promote apoptosis. Treatment with 5 mg/kg PLG obviously inhibited Ang II-induced cardiac hypertrophy and fibrosis in vivo. In vitro studies of neonatal rat cardiomyocytes (NRCMs) showed that the anti-hypertrophic effect of PLG was mediated by reducing the phosphorylation of Akt and thereby preserving the level of Forkhead box transcription factor O1 (FoxO1), since knockdown of FoxO1 by siRNA reversed the protective effect of PLG on NRCMs. In addition, PLG significantly decreased the Ang II-induced expression of profibrotic proteins in neonatal cardiac fibroblasts by reducing the expression of Krüppel-like factor 4 (KLF4) and the recruitment of KLF4 to the promoter regions of transforming growth factor-β and connective tissue growth factor.

CONCLUSION

We demonstrate the cardioprotective effects of PLG in both cardiac hypertrophy and fibrosis and the potential value of PLG for developing novel medications for pathological cardiac hypertrophy and heart failure.

Possible value of galectin-3 on follow-up of cardiac remodeling during glucocorticoid treatment

Glucocorticoids are among the most prescribed drugs globally due to their potent anti-inflammatory and immunosuppressive properties. Although they have positive effects on the treatment of various disease states; long-term administration is associated with high blood pressure, insulin resistance, and susceptibility to type 2 diabetes. The heart attempts to cope with increased blood pressure and a decrease in glucose utilization by developing pathological cardiac remodeling. However, in this process, cardiac fibrosis formation and deterioration in heart structure and functions occur. Galectin-3, a member of the β-galactoside binding lectins, is consistently associated with inflammation and fibrosis in the pathogenesis of various disease states including insulin resistance and heart failure. Galectin-3 expression is markedly increased in activated macrophages and a subset of activated fibroblasts and vascular cells. Also, failing and remodeling myocardium show increased Gal-3 expression and elevated Gal-3 levels are related to heart failure severity and prognosis. Furthermore, Gal-3-related pathways are recently suggested as therapeutic targets both pharmacologically and genetically to increase insulin sensitivity in vivo. The objective of this review is to provide a summary of our current understanding of the role of glucocorticoid-associated insulin resistance, which is important for some cardiac events, and the potential role of galectin in this pathophysiological process.