Impaired Cardiac Function Research Articles

Abstract 4137935: Adipogenesis in Bone Marrow Niche under Cardiac Stress Worsens Cardiac Function

Background: We have recently reported that repetitive cardiac decompensation with multimorbidity often experienced by patients with heart failure (HF) is attributed to epigenetic modifications of hematopoietic stem cells (HSCs) in the bone marrow (BM). HF reprogrammed HSCs differentiation and altered tissue macrophage homeostasis. These findings demonstrate that the BM can carry an innate immune memory of cardiac stress that may exacerbate HF and predispose other organs to pathology. Aims: Because the stemness of HSCs is mainly regulated by mesenchymal stromal cells (MSCs) in the BM niche, we investigated phenotypic alterations of MSCs under cardiac stress. Methods&Results: Transcriptome analysis of MSCs showed preferential differentiation toward adipocytes in murine pressure overload models. In vitro assays and histological BM sections also support this finding. Furthermore, single-cell RNA sequencing of MSCs demonstrated that the percentage of adipocyte-primed MSCs increased in proportion to the severity of cardiac dysfunction, and also correlated with the frequency of myeloid-lineage progenitor cells. To investigate the influence of adipo-lineage MSCs on HSCs, we conducted BM transplantation supplemented with MSCs from control or HF mice. Recipient mice transplanted with HF-MSCs showed significant increases in myeloid-biased multipotent progenitors in BM and myeloid cells in peripheral blood. Additionally, the number of proinflammatory cardiac macrophages was significantly increased in the HF-MSCs group, promoting cardiac fibrosis and dysfunction. Conclusions: Our results demonstrated that the BM niche could perceive cardiac stress in the form of adipocytic skewing of MSCs in the setting of HF, which changed the differentiation behavior in HSCs and ultimately led to further deterioration of cardiac function through the impaired differentiation of circulating monocytes into cardiac macrophages. Therefore, suppressing the adipocytic differentiation of MSCs could have a novel therapeutic potential to avoid repeated HF events.

Abstract 4136452: Acute Cardiac Function Change After Catheter Ablation of Ventricular Arrhythmias in Patients with Arrhythmogenic Right Ventricular Cardiomyopathy

Introduction: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic disorder characterized by fibrofatty replacement of myocardial tissue, creating areas of electrical heterogeneity and increasing the risk of ventricular arrhythmias (VAs) and sudden cardiac death (SCD). Catheter ablation is commonly performed in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) for management of ventricular arrhythmias (VAs). Whether catheter ablation affects cardiac function post-procedurally is uncertain. Research Question: Does catheter ablation for ARVC result in acute change in cardiac function? Goals/Aims: To assess the impact of catheter ablation for VAs on cardiac function in the acute post-procedure setting. Methods: This retrospective study included patients with ARVC who underwent catheter ablation for VAs at Mayo Clinic. Cardiac function was assessed on pre- and post-procedure transthoracic echocardiograms (TTEs). Post-procedure TTEs were obtained within 4 weeks after the ablation procedure. Right ventricular (RV) enlargement and systolic dysfunction were evaluated as continuous variables (0=none, 1=mild, 2=mild-moderate, 3=moderate, 4=moderate-severe, 5=severe). Results: The study included 32 patients who underwent a total of 44 ablations. Mean age at the time of ablation was 49±16 years, and 24 (75%) were male. After a mean follow-up duration of 2.6±5.5 days, there was a significant worsening in mean RV dysfunction (1.6±1.5 to 2.0±1.4, P = 0.001). There were no significant changes in mean left ventricular ejection fraction (LVEF), left ventricular (LV) dimensions, and RV size. 6 (14%) patients had a >5% decline in LVEF, and 14 (32%) patients had worsening RV function. Transient inotropic support was required in 4 (9%) patients. Conclusion(s): This study is the first to assess the acute impact of catheter ablation for VAs on cardiac function in ARVC patients. These results underscore the importance of careful post-procedure monitoring and planning of the ablation target in these patients to avoid excessive ablation and therefore impairment in cardiac function.

IL1RAP Blockade With a Monoclonal Antibody Reduces Cardiac Inflammation and Preserves Heart Function in Viral and Autoimmune Myocarditis.

Currently, there are no therapies targeting specific pathogenic pathways in myocarditis. IL (interleukin)-1 blockade has shown promise in preclinical studies and case reports. We hypothesized that blockade of IL1RAP (IL-1 receptor accessory protein), a shared subunit of the IL-1, IL-33, and IL-36 receptors, could be more efficient than IL-1 blockade alone. We induced coxsackievirus B3 (CVB3)-mediated or experimental autoimmune myocarditis (EAM) in BALB/c mice, followed by treatment with an Fc (fragment crystallizable)-modified mIgG2a mouse anti-mouse IL1RAP monoclonal antibody (mCAN10). Myocarditis severity and immune infiltration were assessed by histology and flow cytometry. Cardiac function was measured by echocardiography. We used spatial transcriptomics (Visium 10× Genomics) to compare the gene expression landscape in the hearts of mCAN10-treated versus control mice. IL1RAP blockade reduced CVB3 and EAM severity. In EAM, the treatment prevented deterioration of cardiac function, measured on day 42 post-disease induction (left ventricular ejection fraction: 56.5% versus 51.0% in isotype controls [P=0.002] and versus 51.4% in mice treated with anti-IL-1β antibodies alone [P=0.003]; n=10-11 mice per group). In the CVB3 model, mCAN10 did not impede viral clearance from the heart and significantly lowered the numbers of CD4+ (cluster of differentiation 4) T cells (P=0.025), inflammatory Ly6C+CCR2+ (lymphocyte antigen 6 complex, locus C/C-C motif chemokine receptor 2) monocytes (P=0.038), neutrophils (P=0.001) and eosinophils (P<0.001) infiltrating the myocardium. The spatial transcriptomic analysis revealed reduced canonical IL-1 signaling and chemokine expression in cardiac immune foci in CVB3-infected mice treated with IL1RAP blockade. Blocking IL1RAP reduces acute CVB3 myocarditis and EAM severity and preserves cardiac function in EAM. We conclude that IL1RAP blockade is a potential therapeutic strategy in viral and autoimmune myocarditis.

Exploring the mechanism of Ling-Gui-Zhu-Gan decoction in metabolic cardiomyopathy via inhibiting ferroptosis

ObjectiveThis study was to investigate the mechanism of Ling-Gui-Zhu-Gan decoction (LGZGD) in regulating lipid metabolism and thus inhibiting ferroptosis. MethodsUPLC for the determination of the main chemical composition of LGZGD. A HF-induced rat model of metabolic cardiomyopathy was established. Echocardiography was used to detect cardiac function. Serum lipid levels, myocardial injury markers, and lipid peroxidation levels were detected. Pathological changes were detected. Lipid deposition was assessed by oil red O, and the mitochondrial ultrastructure was observed by electron microscopy. Mechanistically, PLIN5, CD36, ATGL, GPX4, ACSL4, FPN1, DRP1, MFF, FIS1, and OPA1 expressions were examined. After PA-induced H9c2 cells established, apoptosis, myocardial injury markers, and lipid peroxidation levels were detected and lipid deposition levels were assessed. The expressions of PLIN5, CD36, ATGL, GPX4, ACSL4 and FPN1 were detected. H9c2 cardiomyocytes with transient knockdown of PLIN5 and overexpression of PLIN5 were constructed and treated with drug administration and modeling, and the apoptosis level was detected by flow cytometry, the levels of lipid peroxidation and ROS were detected by fluorescence, and the protein and gene expressions of ACSL4 and GPX4 were detected. Results The main active components of LGZGD were liquiritin, isoliquiritin, cinnamic acid, cinnamaldehyde, glycyrrhizic acid, and atractylenolide III. LGZGD significantly improved cardiac dysfunction, lowered lipid level and lipid deposition, reduced CK, NT-proBNP and MDA levels, restored SOD levels, and improved inflammatory cell infiltration as well as collagen fiber deposition. LGZGD decreased the expression of PLIN5, CD36, ACSL4, and increased the expression of ATGL, GPX4, and FPN1. LGZGD also decreased the gene expression of DRP1, MFF, FIS1, and increased OPA1 expression. LGZGD significantly ameliorated PA-induced apoptosis, decreased lipid deposition, lowered lipid peroxidation levels and CK level, decreased PLIN5, CD36, and ACSL4 expressions, and increased ATGL, GPX4, and FPN1 expressions. LGZGD reversed cardiomyocyte injury aggravated by transient knockdown of PLIN5, decreased apoptosis levels, lipid peroxidation levels, ROS levels, and ACSL4 expressions, and increased GPX4 expression. LGZGD enhanced cardiomyocyte protection after overexpression of PLIN5, reduced apoptosis levels, lipid peroxidation level and ROS level, decreased ACSL4 expression, and increased GPX4 expression. ConclusionPLIN5 interferes with lipid peroxidation, regulates mitochondrial function, and inhibits HF-induced ferroptosis in cardiomyocytes. LGZGD ameliorates impairment of cardiac structural function in model rats through PLIN5-mediated ferroptosis pathway, and has the effect of preventing metabolic cardiomyopathy.

Disfunção Cardíaca Associada À Quimioterapia Em Paciente Pediátrico: Relato De Caso

Introduction: Due to advances in antineoplastic treatments, there has been a notable improvement in the outlook of cancer patients. However, it is crucial to highlight that the cardiotoxicity associated with these therapeutic approaches is recognized as one of the most significant adverse effects. This phenomenon is characterized by the ability of chemical agents or therapeutic procedures to induce damage to the heart muscle, resulting in compromised cardiac function. Objectives: To present a case report of a patient suffering from Non-Hodgkin's Lymphoma (NHL), with impaired cardiac function due to cardiotoxicity. Methods: This is a descriptive observational study, of the case report type, which describes the clinical manifestations and management of a patient with cardiac dysfunction associated with chemotherapy. The research data used were collected through medical records made available by the public health service reference in pediatric oncology in the city of João Pessoa-PB. Results: Report the case of an 18-year-old pediatric patient, diagnosed with non-Hodgkin's Lymphoma, presenting with underlying heart disease, who underwent chemotherapy treatment, developing cardiotoxicity that led to death. Conclusion: Therefore, it is essential that continuous monitoring is implemented throughout the entire cancer treatment. Additionally, it is necessary to ensure that patients have broad access to diagnostic tests and chemotherapy with a cardioprotective profile, aiming to minimize the risk of cardiotoxicity. These measures are essential to reduce the incidence of adverse effects on the myocardium and improve the safety and effectiveness of oncological treatment.

A comprehensive evaluation of available evidence of mavacamten in obstructive HCM: a meta-analysis of randomised controlled trials

Abstract Introduction Obstructive hypertrophic cardiomyopathy (HCM) poses a significant clinical challenge, characterized by left ventricular hypertrophy and impaired cardiac function. mavacamten, a novel medication targeting the sarcomere protein myosin, has emerged as a promising therapeutic option for patients with symptomatic obstructive HCM. Despite its potential efficacy, the comparative effectiveness and safety of Mavacamten remain uncertain, necessitating a comprehensive evaluation of available evidence. Purpose We aimed to give a comprehensive appraisal on mavacamten as a treatment option for patients with obstructive HCM informing clinical decision-making. Methods We systematically searched PubMed, Web of Science, Scopus, and Cochrane Central, and EMBASE from inception until February 2024. We included randomised controlled trials (RCTs) comparing mavacamten versus placebo in patients with obstructive HCM. The primary outcomes were improvement in NYHA class, Change from baseline in KCCQ-CSS, and the incidence of atrial fibrillation. All data were pooled as either Mean difference in the random effect model with the corresponding SD or pooled as RR and 95% CI for dichotomous data. Results Four randomised controlled trials involving 503 patients were included in the final analysis. the overall odds ratio demonstrated a substantial preference for Mavacamten in achieving more than a one-level improvement in NYHA functional class from baseline (OR: 3.83 (95% CI [2.54 to 5.77], P=0.0001). However, there was no significant difference in terms of KCCQ-CSS (MD= 1.06, 95% CI [ -0.03 to 2.15], P=0.06) or the incidence of atrial fibrillation (OR=1.27, 95% CI [0.51 to 3.14], P=0.60). Conclusion Mavacamten showed a significant improvement on NYHA functional class, with no observed significance in terms of reducing the incidence of AF, or improving the KCCQ-CSS score.KCCQ-CSSNYHA

ND15, subunit of the electron transport chain protein-complex I, age-dependently worsens cardiac performance in Drosophila melanogaster

Abstract Introduction In the natural aging process of the heart, aside others, mitochondrial dysfunction is an essential driver for the development of reduced cardiac performance. Previous analysis of protein expression levels in cardiomyocytes of aged mice and have found aberrancies in subunits of the mitochondrial Complexes I – IV of the electron transport chain. Especially, the complex I subunit ND15 was highly downregulated. To elucidate the functional effects of this gene on the cardiac performance, we generated cardiomyocyte specific ND15 knock-downs in Drosophila melanogaster. Methods We generated Drosophila with heart-specific (+/+; Hand4.2-GAL4/UAS-ND15; tdtK/+) (ND15-KD)knockdown of ND15 using the UAS/GAL4 system. The flies' cardiomyocytes endogenously express tdTomato, facilitating fluorescence-based live imaging of the heart by high-resolution video fluorescence microscopy. The recorded data was processed using a R-Script, resulting in Results We compared wild type (WT) flies to ND15-KD flies at age 3 weeks(young) and 7 weeks(old). Knockdown of ND15 resulted in impaired cardiac function. Most parameters deteriorated in aged flies in comparison to young flies. The heart frequency was significantly reduced (WT:6 beats/s – KD:4 beats/s – p&amp;lt;0.0001) in the 7 weeks old group, end-diastolic diameter of the heart tube increased significantly in 3 weeks old ND15KD flies compared to controls(WT:65µm – KD:74µm p&amp;lt;0,0001), resulting in a dilated heart tube Interestingly enough, this dilation in ND15-KD disappeared in 7 weeks old flies. The fractional shortening was significantly decreased in young(WT:33,5% - KD:30% p&amp;lt;0,01) and deteriorated in old flies (WT:35% - KD:22% p&amp;lt;0,0001), indicating a reduced contraction capability. For both 3 weeks and 7 weeks old groups, the heart-rate adjusted interbeat interval variance (WT:22% -KD: 40% p&amp;lt;0,0001) as well as the time of no cardiac action (WT: 22% - KD: 35% p&amp;lt;0,0001) increased and showed significant irregularities. The duration of systole and diastole combined also exhibited arrhythmic patterns (WT:15% - KD:20.5% p&amp;lt;0,0001). A general arrhythmia index (AI) increased significantly (WT: 0.25 – KD:0.5 p&amp;lt;0,0001) These arrhythmia parameters emphasize the arrhythmogenic potential of the ND15-knockdown. The relative relaxation capabilities drastically worsened with age, displaying a diastolic dysfunction in the 7 weeks old group. At half-time relaxation, the WT was at 60% relaxation, ND15KD at 46%). Conclusion This study demonstrates that heart-specific deletion of ND15 results in a marked impairment of systolic and diastolic cardiac function in Drosophila accompanied by pro-arrhythmogenic actions. We could identify ND15 as a new mitochondrial molecular target for the maintenance of regular cardiac function and rhythmicity, especially with increasing age. Further mechanistic studies and translation to mammalian organisms are ongoing.

The transcription factor foxo3 regulates cardiac remodeling after myocardial infarction

Abstract Background Myofibroblast and myeloid cell differentiation following acute myocardial infarction (MI) are important for myocardial fibrosis but also cause adverse remodeling leading to cardiac dysfunction and heart failure. The transcription factor forkhead box O 3 (Foxo3) inhibits hypertrophic cardiac remodeling. We hypothesized that Foxo3, a key regulator of cell differentiation and immunity might inhibit differentiation of fibroblasts and myoloid cells and therefore cardiac fibrosis after MI. Methods MI was induced in Foxo3-/- and wild-type mice by permanent LAD ligation. Cardiac function was determined by transthoracic echocardiography. Cell differentiation was investigated by single nucleus RNA-sequencing (snRNA-seq). Moreover, transdifferentiation assays ex vivo were performed. Results Foxo3-/- mice showed significantly improved survival post- MI (p&amp;lt;0.01) that was in part due to reduced cardiac ruptures (p&amp;lt;0.05). TTE showed reduced LV function, cardiac output, and global strain 4 days post-MI in both groups of animals. However, LV function was significantly attenuated in Foxo3-/- mice 14 d post-MI while diastolic parameters indicated enhanced wall stiffness. snRNA-seq on day 4 post-MI revealed significantly increased numbers of myofibroblasts (p&amp;lt;0.05) transdifferentiating from Progenitor-like state fibroblasts and epicardial derived fibroblasts in Foxo3-/- mice. Myofibroblasts upregulated genes important for extracellular matrix structure and cell migration. Moreover, an upregulation of pro-fibrotic genes was observed in other fibroblast clusters in Foxo3-/- mice and corroborated by significantly elevated collagen type 1 and 3 as well as periostin protein expression. Mechanistically, fibroblasts from Foxo3a-/- mice exhibited enhanced Smad3 dependent myofibroblast marker expression after TGF-ß stimulation. Cell chat analysis indicated enhanced number of interactions and interaction strength of myeloid cells with fibroblasts in Foxo3-/- animals. In line with these observations, differences in cardiac myeloid cell differentiation characterized by reduced center-log ratios of cardiac resident macrophages (Lyve1hiMHCIIlo and Lyve1loMHCIIhi) and increase in monocyte-derived macrophages (Ccr2hi MΦ and Trem2hi MΦ) on day 4 post-MI that was enhanced in Foxo3-/- mice were determined. Differential gene expression patterns on day 4 in pro-inflammatory macrophages (Ccr2hi MΦ) showed upregulation of genes in the interleukin-12 pathway while reparative macrophages (Trem2hi MΦ) revealed an increased expression of genes for extracellular matrix proteins and ECM-collagen interactions in Foxo3-/- mice. Conclusion Our data identify Foxo3 as a master regulator of cardiac remodeling inhibiting myofibroblast and myeloid cell differentiation after acute MI, and suggesting that deficiency of Foxo3 promotes early scar formation but also contributes to adverse matricellular remodeling resulting in impaired cardiac function and enhanced fibrosis.

Myocardial SGLT2 expression and cardiac remodeling in patients with severe aortic stenosis: the BIO-AS Study

Abstract Background Cardiac remodeling plays a major role in the prognosis of patients with aortic stenosis (AS) and could impact the benefits of aortic valve replacement. Blood and tissue biomarkers have a differential pattern and expression level in patients with AS, which may retain a pathophysiological role in cardiac remodeling and metabolism. However, the data available are limited and contradictory. Aim Our study aimed to evaluate the expression of sodium-glucose cotransporter 2 (SGLT2) gene and protein in patients with severe AS stratified in high gradient (HG) and low flow-low gradient (LF-LG) AS and its association with cardiac functional impairments. Methods Gene expression and protein levels of main biomarkers of cardiac fibrosis (Galectin-3, sST2, Serpin-4, PINP, PICP, Collagen, TGF-b), inflammation (GDF-15, IL-6, NF-kB), oxidative stress (SOD1, SOD2), and cardiac metabolism (NHE, PPAR-a, PPAR-g, GLUT1, and GLUT4) were evaluated in blood samples and heart biopsies of 45 patients with AS. Results Our study showed SGLT2 gene and protein hyper-expression in patients with LF-LG AS, compared to controls and HG AS (p&amp;lt;0.05). These differences remained significant even after adjusting for age, gender, body mass index, history of diabetes mellitus, arterial hypertension, and coronary artery disease. SGLT2 gene expression was positively correlated with: i) TGF-b (r=0.72, p&amp;lt;0.001) and collagen (r=0.73, p&amp;lt;0.001) as markers of fibrosis; ii) NF-kB (r=0.36, p&amp;lt;0.01) and myocardial IL-6 (r=0.68, p&amp;lt;0.001) as markers of inflammation: iii) SOD2 (r=-0.38, p&amp;lt;0.006) as a marker of oxidative stress; iv) GLUT4 (r= 0.33, p&amp;lt;0.02) and PPAR-a (r=0.36, p&amp;lt;0.01) as markers of cardiac metabolism (Figure 1). Conclusion In patients with LF-LG AS, SGLT2 gene and protein were hyper-expressed in cardiomyocytes and associated with myocardial fibrosis, inflammation, and oxidative stress. The hyper-expression of the SGLT2 gene and protein in patients with LF-LG might pave the way for using SGLT2-Is in this subset population, with the potential to improve the outcomes of AVR and reduce the likelihood of re-hospitalization within one year.Figure 1

Associations of different definitions of iron deficiency with cardiac structure and function, congestion, exercise capacity and prognosis in heart failure

Abstract Background It is uncertain how best to diagnose iron deficiency (ID) in patients with heart failure (HF) as different ID definitions have been proposed with discordant results. Objectives To assess the relationship of different ID definitions with cardiac structure and function, congestion, exercise capacity, and prognosis in outpatients with HF. Methods ID was defined according to guidelines (G-ID: ferritin &amp;lt;100 ng/mL or ferritin 100-299 ng/mL with transferrin saturation [TSAT] &amp;lt;20%) or as TSAT &amp;lt;20%. Alternative definitions (iron &amp;lt;13 ¼mol/L, ferritin &amp;lt;100 and &amp;lt;300 ng/mL) were explored. Relationship with rest and exercise ultrasound findings, cardiopulmonary exercise testing and a composite endpoint of cardiovascular hospitalisations or all-cause mortality were assessed. Results Of 1502 patients (72% with left ventricular ejection fraction [LVEF] ≥50%), 471 (31%) had TSAT &amp;lt;20%, while 728 (48%) had G-ID. Compared to those without ID, patients with TSAT &amp;lt;20% or G-ID showed impaired cardiac structure and function at rest and peak exercise and lower peak oxygen consumption; they were also more likely to display a discontinuous renal venous flow pattern and more lung B-lines. Only TSAT &amp;lt;20% was associated with significant inferior vena cava dilatation. Lower TSAT, iron and haemoglobin were associated with more severe effort intolerance and ultrasound signs of congestion, while ferritin and LVEF were not (Picture 1). During a median follow-up of 16 months, 62 (4%) patients died, and 244 (16%) were hospitalised for cardiovascular reasons. No patients were hospitalised immediately after the enrolment visit because of clinical findings. At Kaplan-Meier analyses, TSAT &amp;lt;20% was associated with a greater risk of adverse events, as were iron ≤13 ¼mol/L, ferritin ≥300 ng/mL and &amp;lt;100 ng/mL (p &amp;lt;0.01 vs ferritin 100-299 ng/mL) and G-ID (Picture 2). After adjusting for age, sex, diabetes, haemoglobin, estimated glomerular filtration rate (eGFR), NT-proBNP, rest LVEF and peak VO2 &amp;lt;16 mL/kg/min, TSAT &amp;lt;20% and iron ≤13 ¼mol/L were associated with worse outcomes (hazard ratio 2.41, 95% confidence interval 1.85-3.14 and 1.90, 1.46-2.47), while G-ID or ferritin &amp;lt;100 or &amp;lt;300 ng/mL were not (Picture 1). Conclusions In outpatients with HF, TSAT &amp;lt;20% is more consistently associated with echocardiographic signs of poorer functional capacity and multi-organ congestion than other ID definitions. TSAT &amp;lt;20% and iron ≤13 ¼mol/L, but not G-ID or ferritin-based ID, seem to predict a worse prognosis.Picture 1Picture 2

S-nitrosylation of aconitase-2 facilitates coronary microembolization-induced cardiac injury by suppressing iron-sulfur cluster assembly

Abstract Background Coronary microembolization (CME) is a common reason for periprocedural myocardial infarction after coronary interventions. S-nitrosylation (SNO), a prototypic redox-based posttranslational modification, is involved in the pathogenesis of several cardiovascular diseases. Purpose To explore the role of SNO of aconitase-2 (ACO2) in CME-induced cardiac injury, as well as the mechanism by which SNO-ACO2 modulates myocardial injury in response to CME. Methods CME models were established in C57BL/6J mice by injecting 300,000 polyethylene microspheres (diameter 9 µm) into the left ventricle chamber with the occlusion of the ascending aorta. Cardiac function was evaluated by echocardiography. Histological and serum analysis was performed to evaluate myocardial injury. Myocardial samples were scanned for S-nitrosylated proteins using biotin-switch procedures and liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis. SNO sites of ACO2 were further identified through LC-MS/MS. De-nitrosylation of ACO2 was achieved by the mutation of SNO site or overexpression of the de-nitrosylation enzyme thioredoxin 1 (TRX1). Interacting effectors of SNO- ACO2 were screened through LC-MS/MS and confirmed by coimmunoprecipitation. Neonatal rat ventricular myocytes (NRVMs) were used for in vitro study. The cellular ACO2 activity was analysed using an ACO2 enzyme activity assay kit. Mitochondrial morphology and function were assessed by fluorescent staining and mitochondrial stress testing. Results Cardiac injury was exacerbated by CME as demonstrated by impaired cardiac contractile function, morphological changes, and increased fibrosis, microinfarct size and serum troponin I level. We identified 789 S-nitrosylated proteins in CME mouse hearts, and ACO2 is one of the highly S-nitrosylated proteins. The increased level of SNO-ACO2 was verified by immunoblot assay in CME mouse hearts and hypoxia-stimulated NRVMs. SNO site of ACO2 at cysteine 126 was identified by LC-MS/MS and confirmed in NRVMs. De-nitrosylation of ACO2 by the mutation of cysteine 126 or overexpression of TRX1 both greatly improved the activity of ACO2 by 39.7% and 31.4% respectively, furthermore restored the mitochondrial function, and attenuated CME-induced cardiac injury. Mechanistically, SNO-ACO2 at cysteine 126 suppressed the interaction between ACO2 and NFU1, an iron-sulfur (Fe-S) cluster scaffold protein. The dissociation from NFU1 deprived ACO2 of the Fe-S cluster and the enzyme activity, thereby promoting the disruption of the mitochondrial tricarboxylic acid cycle and cardiac injury. Conclusions Our data defined a previously unrecognized role of SNO-ACO2 in CME-induced cardiac injury. We demonstrated that SNO-ACO2 at cysteine 126 disrupted ACO2/NFU1 interaction to exacerbate myocardial injury after CME. Our results suggested that de-nitrosylation of ACO2 may provide a new therapeutic target for the treatment of CME.

Chronic inflammation is associated with impaired cardiac structure and function in patients with inflammatory arthritis: the ARTCADIA Study

Abstract Background Inflammation as an underlying cause of cardiac dysfunction has been underscored in recent years. Patients with inflammatory arthritis (IA) are at risk of being exposed to a high degree of chronic and systemic inflammation. It is therefore important to investigate whether high inflammatory burden impacts cardiac structure and function in patients with IA. Purpose To examine the impact of long-term inflammation on measures of cardiac structure and function in individuals with rheumatoid arthritis (RA) and axial Spondyloarthritis (axSpA), collectively referred to as IA, in a large cohort. Methods In a prospective cohort study, outpatients with a diagnosis of IA were included over two years during their biannual rheumatological routine appointment. In total, 1,285 participants were included. Participants were evaluated at a cardiology research center where echocardiography was performed following a pre-defined protocol. To evaluate chronic inflammation, C-reactive protein (CRP) was averaged from clinical outpatient visits registered in a rheumatological database. Uni- and multivariable linear regressions were used to examine the relationship between echocardiographic measures and log-transformed CRP. Results Among the 1,285 participants, 903 (70%) were diagnosed with RA, 358 (28%) with axSpA, and 24 (2%) with other forms of IA. Mean age was 60 ± 13 years, 64% were female. The median number of outpatient visits was 30 (Interquartile range (IQR): 18 - 48), median disease duration was 12 (IQR: 6 - 20) years, and the median outpatient CRP was 5.7 (IQR: 3.7 – 9.8) mg/L. 519 (40%) patients had hypertension (HT), 113 (9%) diabetes mellitus (DM), 76 (5.9%) ischemic heart disease (IHD) and 35 (2.5%) heart failure (HF). Mean left ventricular (LV) ejection fraction was 54.6 ± 5.7%, mean numerical global longitudinal strain (GLS) was 17.8 ± 2.4%, mean LV mass index (LVMi) was 73 ± 18 g/m2 and mean tricuspid annular plane systolic excursion (TAPSE) was 2.5 ± 0.4 cm. In univariable analyses, higher levels of CRP were significantly associated with lower GLS, p &amp;lt; 0.001; higher E/e’, p = 0.001; higher LVMi, p &amp;lt; 0.001 and lower TAPSE, p = 0.005 (Figure). The associations remained significant after adjusting for clinical characteristics including disease duration, age, sex, blood pressure, body mass index, physical activity, pack-years of smoking, cholesterol, HT, DM, heart rate, atrial fibrillation, IHD and HF (p &amp;lt; 0.05 for all associations). We observed no significant interactions between the IA diagnosis and inflammation across the significant echocardiographic measures. Conclusion In a large cohort of patients with IA, increasing levels of chronic inflammation determined by outpatient CRP was associated with impaired measures of cardiac structure and function and remained significant after adjusting for clinical characteristics. The prognostic and clinical implication of these findings needs to be explored in future studies.Linear regression splines

Changes in peak oxygen consumption on excercise and cardiomyopathy disease stage in Fabry disease

Abstract Background Fabry disease (FD) is an X-linked lysosomal storage disorder manifesting as deficiency in the enzyme α-Galactosidase A (1) resulting in multi-organ accumulation of globotriaosylceramide (Gb3) (2) This causes predominantly cardiac, renal and cerebrovascular manifestations. Shortness of breath and exercise intolerance are common and can be related to multiple underlying mechanisms. Cardiopulmonary exercise testing (CPEX) quantifies aerobic fitness, functional capacity, chronotropic and haemodynamic response to exercise, and attributes effort intolerance to different aetiologies, including impaired cardiac and respiratory function. Purpose We hypothesise that there is progressive effort intolerance that reflects continual cardiac Gb3 accumulation, becoming common during myocardial hypertrophy and disabling in the fibrosis and inflammation stage. The aims of this study were to ascertain frequency and severity of exercise intolerance in FD by investigating the relationship between peak maximal oxygen uptake (VO2 max) and cardiac disease stage, quantified based on a four-point scale, as proposed in published literature (3). Methods This was a retrospective review of adults with FD and exercise intolerance attending a specialist clinic who had undergone either CPEX or six-minute walk testing (6MWT) in those less mobile. Biochemical, cardiac magnetic resonance (CMR) imaging and transthoracic echocardiographic (TTE) data were also collected. Results N=54 patients underwent CPEX and N=35 patient underwent 6MWT. Estimated peak VO2 max was calculated using 6MWD in those undergoing 6MWT. Median age was 54 (IQR 40-62) years and 53% were male. Patients were equally distributed across disease stage (1-4). There were significant trends in age (increasing) and gender (male predominance) from stage 1-4. Age/sex-normalised peak VO2 max values were calculated as per published literature due to the confounding effect of age and male gender. Mean normalised VO2 max was 35.5ml/kg/min for the cohort, an underperformance of 12.3 ± 8.0 ml/kg/min. The magnitude of underperformance began from stage 1 (no cardiomyopathy) and increased with each stage (Figure 1). Impairments in renal (creatinine and albumin: creatinine ratio) and cardiac biomarkers (troponin and N-terminal pro brain natriuretic peptide) was associated with reduced VO2 max (Table 1). Increased indexed left ventricular mass on CMR and impairments in atrial volume and function on TTE were also associated with a reduction in VO2 max (Table 1). Conclusion This study is the first of its kind to demonstrate impairments in peak aerobic capacity in adults with FD and no cardiomyopathy (stage 1) which impairs further with cardiac disease stage. Future work should focus on how disease-modifying therapy can target this using VO2 as an endpoint and marker of response.Normalised peak VO2 max + disease stageVO2 max and blood / imaging parameters

Relationships between 18-month kinetics and functional capacity and left ventricular remodeling and cardiac fibrosis in dilated cardiomyopathy

Abstract Introduction Myocardial fibrosis is a primary pathogenetic process in dilated cardiomyopathy (DCM) that is responsible for progressive cardiac remodeling and functional capacity impairment. We sought to verify whether there were differences between 18-month kinetics of functional capacity and left ventricular remodeling in DCM patients with different types and advancement of fibrosis who were up-titrated with guideline directed pharmacotherapy (GDMT). Methods Between May 2019 and September 2020, 99 DCM patients (88 male, mean age 45.2 ± 11.8 years, mean EF 29.7 ± 10%) underwent cardiac magnetic resonance with assessment of replacement fibrosis via late gadolinium enhancement (LGE) and interstitial fibrosis via extracellular volume (ECV). Each patient had serial (baseline, 6-, 12-, 18 month) functional assessment: NYHA class and 6- minute walking test (6-MWT) and follow-up echocardiography, including measurement of left ventricular end-diastolic volume (LVEDvol) and ejection fraction (EF). Patients were divided into LGE-negative and LGE-positive groups, whereas based on median ECV – they were divided into those with ECV below and above median values. Results Overall, LGE was identified in 44 (44%) of patients, whereas median ECV was 27.7%. NYHA class was significantly worse in patients with LGE (1.5±0.5 vs. 1.9±0.6) and with higher ECV (1.93±0.6 vs. 1.6±0.5) in comparison to those without LGE and lower ECV. However, NYHA class improved during observational period in all groups. There were no differences in 6-MWT distance in LGE positive and negative groups at all time points. Baseline 6-MWT distance in LGE positive group was 494.2±88.2 vs. 453.9±98.8 meters in LGE negative group. Baseline 6-MWT distance in upper median ECV group was (408.8±103.5 vs. 492.4±92.9 meter) was significantly lower ECV group (p=0.03). During 18 months 6-MWT distance increased only in LGE negative group but in both ECV groups (Figure 1 A-D). There were no differences in EF between patients with and without LGE and also with higher and lower ECV. Baseline EF in LGE positive group was 27.4±11.2% and 31.7±10.6% in LGE negative. Baseline indexed LVEDvol in LGE positive group was 107.7±40.7 vs. 91.8±37.8 ml/m2 (p=0.09) in LGE negative group. EF increased significantly in both groups, whereas indexed LVEDvol decreased only in LGE negative group (Figure 2 A-D). Conclusions Regardless of the presence of replacement and to some extent of interstitial fibrosis, functional and cardiac morphological improvement was observed during 18 months observation in DCM patients on GDMT. The greatest improvement occurred during the first 3 (occasionally 6) months which was associated with the greatest escalation of GDMT. Further dose escalation was not associated with a significant improvement in both functional and morphological parameters.

Exaggerated blood pressure response to submaximal exercise must be considered relative to fitness: strong associations with hypertensive target organ damage

Abstract Exaggerated systolic blood pressure (SBP) during submaximal exercise is associated with increased cardiovascular (CV) risk. However, findings are mixed and new evidence indicates that cardiorespiratory fitness should be considered for proper clinical interpretation of exercise SBP responses. This study aimed to determine the relationship between SBP response to submaximal effort corrected for fitness and abnormalities of cardiac structure and function. Methods Each of 231 participants (age 54±12 years; 53% females) with controlled clinic BP, no evidence for ischemic heart disease, valvular heart disease or heart failure underwent cardiopulmonary exercise testing (Bruce protocol), resting and exercise echocardiography and 24h ABPM. Submaximal exercise SBP (measured at the 2nd stage of Bruce protocol) was corrected for two fitness variables: 1) peak VO2 and 2) maximal workload in METs (SBP/peakVO2 and SBP/METs). Results There were no, or weak, associations with exercise SBP and target organ damage. However, there was a progressive deterioration of cardiac function and structure parameters across the exercise SBP tertiles corrected for fitness (Table 1). Both SBP/peakVO2 and SBP/METs significantly correlated with left ventricular (LV) mass, LV diastolic and systolic, and left atrial parameters (Table 2). ROC analysis revealed good performance of corrected SBP response to submaximal exercise in detection of LV hypertrophy and diastolic dysfunction (AUC 0.792 and 0.808, and 0.771 and 0.802 for SBP/peakVO2 and SBP/METs, respectively; Figure). Conclusions Fitness-corrected SBP responses to submaximal exercise can identify more profound target organ damage with respect to cardiac function and structure even among patients with controlled clinic BP. Exaggerated BP response to exercise must be considered relative to fitness for proper clinical interpretation of BP responses to exercise testing.Figure

METTL3 drives heart failure by regulating Spp1 and Fos m6A modification in myocardial infarction

Abstract Background While m6A modification has been reported in myocardial infarction (MI), the detailed mechanism by which METTL3 regulates the progression of the disease has not yet been elucidated, and it remains unclear why m6A modification increases after MI. Purpose To investigate the role and mechanism of METTL3 in regulating its targets through m6A methylation in MI. The research results will not only add new content to the basic mechanism of myocardial protection but also provide new ideas and new targets for the prevention and treatment of MI. Methods Through MeRIP-seq and extensive bioinformatics analysis, the target genes SPP1 and FOS with the most significant m6A modification and differential expression in MI were screened. We successfully constructed heart specific Mettl3 knockout mice (Mettl3CKO) to verify that METTL3 promotes the deterioration of cardiac function after MI. We performed complementary molecular methods to assess protein quantity and interactions to identify mechanisms regulating this response. We manipulated select molecular pathways using both genetic and pharmacological methods to validate these mechanisms. Results Here, we showed that METTL3 exerted methyltransferase activity-dependent functions in gene regulation in MI, and a significant transcription factor HuR assisted the function of METTL3. and demonstrated that METTL3 was critical for the promotion of heart failure after MI. More specifically, METTL3 directly interacted with HuR through its nuclear localization domain in the cell nucleus under normoxia condition. When hypoxia developed, METTL3 separated from HuR and deposited m6A into 5’UTR of Spp1 and Fos mRNA to maintain their stability. In contrast, HuR bound to the ARE domain of 3’UTR of Spp1 and Fos mRNA to take them to the cytosol, maintaining their stability. Moreover, HIF-1α directly interacted with the HRE domain of Mettl3 to promote its transcription, and HuR bound to the ARE domain of 3’UTR of Mettl3 mRNA to maintain its stability to promote following translation. Conclusions Collectively, our studies revealed previously unappreciated functions of METTL3 with the help of HuR, and a direct target of HIF-1α under normoxia condition, which together contribute to its essential function in MI, suggesting therapeutic potential for targeting the METTL3/HuR/Spp1(Fos) mRNA axis.Figure1

Heritable heart failure traits in mice undergoing early life stress

Abstract Introduction Adverse childhood experiences, known as early life stress (ELS), are associated with increased cardiovascular disease risk in later life, yet the underlying mechanisms remain elusive. Recent evidence indicates that parental life experiences can be transmitted to the offspring. Whether ELS exerts transgenerational effects on the heart is unknown. Purpose To investigate the effects of ELS on cardiac structure and function in exposed parents and in their offspring, across 3 generations. Methods We used a mouse model of ELS (MSUS) that mimics the exposure to traumatic experiences during childhood in humans. Mouse pups (F1) were separated from their mother (F0) unpredictably each day for 3 hours from postnatal day 1 (PND1) to PND14. During separation, dams were exposed to an additional unpredictable stressor by being subjected to either, a forced swim (18°C water for 5 minutes) or a 20-minute physical tube restraint, anytime (unpredictably) during the 3 hours. From PND15, mice are left undisturbed with their mother until PND21, are then raised normally until adulthood. Control litters were raised normally. A high-resolution Micro-Ultrasound System (Vevo 3100, Visualsonics) was used for the echocardiographic assessment at 6, 12 and 18 months both in the exposed animals (F0) as well as in their offspring (F1) and grandoffspring (F2). Both male and female mice were studied. Heart weight/tibia length and left ventricle weight/tibia length were used to assess cardiac mass while myocardial fibrosis was assessed by Masson's Trichrome and Picriosirius Red stainings. Lung congestion was assessed as lung wet/dry weight ratio. Single cell RNA sequencing (scRNAseq) was used in LV specimens from MSUS mice to unveil cell-specific transcriptional changes. Finally, MSUS mice underwent environmental enrichment (cages containing running wheels, maze) to investigate any rescuing effect on cardiac function. Results F1 mice displayed increased LV mass, impaired diastolic function, myocardial fibrosis and lung congestion. A time-dependent worsening of cardiac performance was observed from 6 to 18 months, both in males and females. ScRNAseq unveiled dysregulation of transcriptional programs underlying inflammation and lipotoxicity in the cardiomyocyte and endothelial cell clusters. The MSUS offspring did not show changes of cardiac function at 6 months, however diastolic dysfunction and lung congestion were observed at 12 and 18 months. A similar impairment of cardiac function was observed in the MSUS grandoffspring (F3). Of interest, 6-week exposure to an environmental enrichment protocol was able to improve LV mass, diastolic function and lung congestion in 12 months-old MSUS mice. Conclusions ELS induces a transgenerational transmission of cardiac phenotypic alterations which can be rescued by EE. Our results shed light on the potential role of ELS on heart failure development and potential mitigation strategies.

Clinical profile of patients undergoing percutaneous stellate ganglion block for electrical storm and association with antiarrhythmic efficacy

Abstract Background Percutaneous stellate ganglion block (PSGB) usage for patients with refractory ventricular arrhythmias (VAs) in form of electrical storm (ES) is in quickly expanding. The clinical profile of patients and the potential association with the antiarrhythmic efficacy of the procedure are mostly unexplored. Purpose To better characterize clinical profile and potential association with antiarrhythmic efficacy of patients undergoing PSGB for ES. Methods Patients undergoing PSGB for ES in our Center from 2/2021 to 2/2024 were enrolled; all the dynamic variables were evaluated in a per procedure analysis. Results 45 patients (93% male, 64 ± 10 years) received a total of 80 PSGB performed with the lateral, ultrasound (US) guided technique; most PSGB consisted of a single bolus anesthetic injection (lidocaine + ropivacaine), 26% in an additional continuous infusion, mostly with ropivacaine. All procedures except for 3 in a single patient who had previously received left cardiac sympathetic denervation, were performed on the left side. Most of the patients (60%) suffered ischemic cardiomyopathy (CMP), including 10 with an acute coronary syndrome; the rest had non-ischemic CMP; 60% had an ICD. The type of VAs was ventricular tachycardia (VTs) only in 86% of the procedures (cycle length 404 ± 143 msec), VT and VF in 10% and VF only in 3 (4%). Most PSGB (81%) were performed in the setting of impending or manifest cardiogenic shock (SCAI classification B or more), including 20% with sepsis. Cardiac US performed before (within 12 hours) each PSGB showed a severely depressed left ventricular (LV) function (mean LVEF 22 ± 10%, mean LV outflow tract velocity time integral 12 ± 4 cm), calculated at a mean heart rate of 81 ± 16 bpm. Mean LVEDV was 252 ± 104 ml, 79% had mitral regurgitation (MR) ≥2+/4+ (including 39% severe MR), 50% had ≥ moderate diastolic dysfunction, 29% had right ventricular dysfunction (mean fractional areal change 33± 7%). Most cases (75%) experienced a complete VAs suppression (sustained or treated) in the 12 hours after PSGB; only 3/80 cases required additional urgent antiarrhythmic strategies (intra-aortic ballon pump in one case, urgent pacing in another one, urgent revascularization in the last one). None of the assessed clinical or echocardiographic characteristics was significantly associated with VT cycle length or the response to PSGB. Only 1 (1%) major complication occurred (respiratory arrest), that was quickly and effectively treated with lipid emulsion. Conclusions PSGB in our Center was mostly performed in the setting of primary impending or manifest cardiogenic shock with severely impaired cardiac function, with an excellent safety profile. None of the assessed clinical or echocardiographic variables were associated with response to PSGB. Our data, despite preliminary and requiring confirmation, suggests always considering PSGB in the urgent/emergent setting independently from patients’ characteristics.

Differential postnatal cardiovascular course of donor-recipient twins and associated pathophysiology-a cohort study.

Fetal echocardiography in twin to twin transfusion pregnancies treated with photocoagulation noted impaired cardiac function. Systematic information about cardiac structure or function and arterial distensibility after birth is not available. This study evaluated cardiovascular function and arterial dynamic properties in survivors of twin to twin transfusion syndrome. Eleven pairs of donor-recipient twins were compared with each other, and with 20 singletons of comparable gestational age. The twin cohort was born at 31.5±2 weeks gestational age; birthweights of donors-recipients were comparable (donors: 1358±421g vs recipients: 1617±460g, P=0.2). Significant inter-twin differences were noted for cardiac function parameters. Recipients had greater septal thickness (donors: 2.3±0.15 vs recipients: 2.7±0.36mm, P=0.01) and globularity (lower sphericity index [donors: 1.76±0.1 vs recipients: 1.62±0.12, P=0.009]). They also had lower cardiac function (tricuspid annular plane systolic excursion [donors: 4.6±0.5 vs recipients: 4.1±0.4mm, P=0.02) and right ventricular fractional area change [donors: 30±1 vs recipients: 27.7±1.3%, P=0.0001]). Comparing with singletons, differences were statistically more significant for recipients. Arterial distensibility however, was more affected in donors (higher arterial wall stiffness index [donors: 2.5±0.2 vs recipients: 2.2±0.2, P=0.008] and lower pulsatile diameter [donors: 51±5 vs recipients: 63±10 µm, P<0.0001). Comparing with singletons, the differences were statistically more significant for donors. Evaluation in the neonatal period noted that cardiac function and arterial distensibility is affected in TTTS twins. These cohorts will benefit from close postnatal follow up for resolution of cardiac and arterial impairments.

Effects of Atezolizumab plus Bevacizumab on Skeletal Muscle Volume and Cardiac Function in Patients with Hepatocellular Carcinoma

Introduction: Pharmacological treatment of unresectable hepatocellular carcinoma (uHCC) includes sorafenib and lenvatinib, a tyrosine kinase inhibitor, which are linked to low serum levels of carnitine and reduced skeletal muscle volume. Nowadays, atezolizumab plus bevacizumab (Atezo/Bev) combination therapy is recommended as the first-line treatment for patients with uHCC. However, the association with decreased muscle mass or cardiac function is unknown. Therefore, this study aimed to evaluate the effects of Atezo/Bev on skeletal muscle volume and cardiac function in patients with uHCC. Methods: This retrospective study included 55 adult Japanese patients with chronic liver diseases and uHCC treated with Atezo/Bev. Patients were divided into three groups according to age: middle, preold, and old. Serum levels of carnitine and cardiac function were measured before and after 3 weeks of treatment. The psoas muscle index (PMI) was measured before and after 6 weeks of treatment. Results: After treatment, the global longitudinal strain was significantly lower in the old group, whereas the PMI and ejection fraction were significantly lower in the preold and old groups. However, no significant difference in serum levels of total carnitine and those fractions with treatment in each group was found. Cardiac function decreased in the preold and old groups. Conclusion: When treating patients with uHCC by Atezo/Bev, caution should be taken in preold and old patients because they are vulnerable to decreased skeletal muscle mass and deterioration of cardiac function. Strength training and regular monitoring of cardiac function are encouraged in these groups.