Search PubMedSearch

SEARCH · Search PubMed

Results for “Ventricular Remodeling”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Effects of Sacubitril Valsartan Combined With Vericiguat on NT-proBNP and CK-MB Levels in Patients With Chronic Heart Failure.

This study aims to probe the influence of sacubitril valsartan sodium tablets combined with vericiguat on N-terminal pro-B-type natriuretic peptide (NT-proBNP) and creatine kinase isoenzyme (CK-MB) levels in patients with chronic heart failure (CHF). One hundred and twenty CHF patients were enrolled and stratified into a control group (sacubitril valsartan sodium tablets) and a combination group (sacubitril valsartan sodium tablets + vericiguat). Outcome measures included New York Heart Association (NYHA) functional class shifts, echocardiographic indices, cardiac injury markers, 6-min walk distance (6MWD), endothelial function parameters, inflammatory mediator levels, and adverse clinical events. Following a 6-month treatment period, patients in the combination group exhibited superior functional improvement, as reflected by greater advancement in NYHA class. Echocardiographic evaluation revealed more favorable ventricular remodeling in this group, with reduced left ventricular end-diastolic and end-systolic diameters and an elevated ejection fraction. The combination group had a higher 6MWD. Biomarker analysis showed lower NT-proBNP and CK-MB levels in the combination group. Furthermore, improvements in endothelial function were noted, with decreased endothelin and elevated NO, NOS, and CGRP levels in the combination group. Markers of systemic inflammation, including CRP and IL-6, were also attenuated in the combination group. The incidence of adverse reactions and cardiovascular events did not differ significantly between the groups. Co-administration of sacubitril/valsartan and vericiguat enhances cardiac performance, optimizes vascular endothelial responsiveness, modulates heart failure-related biomarkers, and mitigates inflammatory activity in patients with CHF without increasing the risk of adverse events.

Humans

Home blood pressure telemonitoring reveals race-specific patterns of target organ damage.

BACKGROUND: Racial differences in cardiac and renal target organ damage (TOD) may persist at comparable blood pressure levels. This study compared TOD in high-risk, non-African-American Black and White patients in relation to the home blood pressure (HBP). METHODS: UPRIGHT-HTM (NCT04299529) is an ongoing international trial comparing risk stratification strategies in asymptomatic patients, aged 55-75 &#x200a;years, with &#x2265;5 risk factors. Patients engage in HBP telemonitoring (OMRON HEM 9210-T). After 34.7&#x200a;months (median), 287 Black and 154 White patients underwent echocardiography. At baseline, their chronic kidney disease (CKD) grade was assessed by cross-classification of the race-free estimated glomerular filtration rate and albuminuria (2024 KDIGO guideline). HBP was stratified by the 2024 ESC thresholds. Linear and logistic regression models, including a race-by-HBP interaction term, were applied to assess associations with the home systolic HBP. RESULTS: The number of HBP readings was 252 215. Median systolic/diastolic HBP was 127/77&#x200a;mmHg with 142 patients (32.2%) having home hypertension. Fewer Black patients received statins or combination therapy for hypertension or diabetes. Among nonhypertensive White compared to Black patients, left atrial dimensions, mitral annular s', and stroke volume had a steeper slope in relation to systolic HBP. All patients had concentric left ventricular remodeling, but only 4 Black and 13 White patients had an ejection fraction&#x200a;<&#x200a;50%. CKD grade was worse in Black than White patients without association with HBP. CONCLUSIONS: TOD primarily affects the kidney in Black and the heart in White patients. Intensifying pharmacological treatment in sub-Saharan Africa, including antihypertensives, lipid-lowering agents, antidiabetic medications, and aspirin, should create an opportunity for improved overall cardiovascular and metabolic prevention.

Aged

Generation and Phenotypic Characterization of a CRISPR/Cas9-Engineered Cracd-Deficient Mouse Model for Post-Myocardial Infarction Remodeling Studies.

Myocardial infarction (MI) remains a major cause of morbidity and mortality worldwide. This protocol describes a method for generating and characterizing a Cracd-deficient mouse line on the C57BL/6N background using CRISPR/Cas9 technology. Zygotes were co-injected with Cas9 mRNA, a gRNA construct, and a donor template designed to generate a 3153-bp genomic deletion. The edited allele was confirmed by PCR genotyping and Sanger sequencing. To assess the functional role of CRACD in post-MI remodeling, Cracd-deficient and wild-type (WT, C57BL/6N) mice underwent MI induced by permanent ligation of the left anterior descending coronary artery. On postoperative day 7, cardiac function and left ventricular wall motion were assessed using transthoracic echocardiography and speckle-tracking strain imaging, followed by histopathological evaluation with H&E and Masson's trichrome staining. Representative results showed that Cracd-deficient mice exhibited reduced ventricular dilation and preserved systolic function compared to WT controls. This protocol provides a reliable experimental platform for mechanistic studies of CRACD in cardiac pathophysiology.

Animals

Physical Activity and Cardiovascular Outcomes in Phenotype-Negative Cardiomyopathy Variant Carriers.

IMPORTANCE: Exercise may lead to disease progression and higher risk of sudden death in individuals with genetic cardiomyopathies, but the effects of exercise among individuals carrying a cardiomyopathy-associated variant without clinical manifestations (G+P-) are unclear. OBJECTIVE: To examine whether the effects of moderate to vigorous physical activity (MVPA) on cardiovascular (CV) outcomes, cardiac structure and function, and risk of developing overt cardiomyopathy and malignant ventricular arrhythmias (VAs) vary by G+P- status. DESIGN, SETTING, AND PARTICIPANTS: UK Biobank participants with whole-genome sequencing providing 1 week of accelerometer-based physical activity data and without prevalent heart failure (HF), atrial fibrillation (AF), cardiomyopathy, VAs, or implantable cardioverter-defibrillators were included in this cohort study. The study was conducted at 22 assessment centers throughout the UK from February 2013 to December 2015 with a median follow-up of 8 years. Data were analyzed from March 2024 to June 2025. EXPOSURE: Accelerometer-measured MVPA (minutes/week). MAIN OUTCOMES AND MEASURES: Associations were analyzed between MVPA volume and future incidence of adverse CV outcomes (AF, HF, myocardial infarction [MI], and stroke), cardiac magnetic resonance (CMR)-based measures of cardiac remodeling, and surrogates for clinical cardiomyopathy onset (cardiomyopathy and VA). Associations were compared between G+P- carriers and noncarriers. RESULTS: Among 84&#x202f;699 individuals (mean [SD] age, 62 [8] years; 48&#x202f;353 [57%] women; 3979 G+P- carriers), greater MVPA was associated with a lower risk of adverse CV outcomes over a median (IQR) 8.0 (7.5-8.5) years, irrespective of genotype. In multivariable models, higher MVPA was broadly associated with lower risk of incident CV disease in G+P- carriers (hazard ratio [HR] at optimal MVPA level vs zero [95% CI], AF: 0.68 [0.58-0.79]; HF: 0.58 [0.47-0.71]; MI: 0.49, [0.24-1.00]; stroke: 0.35 [0.12-0.99]). For G+P- carriers, MVPA in the range of 100 to 400 minutes per week was generally associated with lowest risk. Among individuals with CMR imaging, MVPA was associated with a similar pattern and extent of cardiac remodeling (eg, left ventricular dilation and left ventricular hypertrophy) in G+P- carriers vs noncarriers. Among G+P- carriers, higher MVPA was associated with lower risk of incident cardiomyopathy (HR at optimal MVPA vs 0, 0.03; 95% CI, 0.00-0.98) with no increase in risk of VA (eg, HR at 400 minutes of MVPA vs 0, 0.98; 95% CI, 0.83-1.14). Findings were generally consistent across variants associated with dilated cardiomyopathy, hypertrophic cardiomyopathy, or arrhythmogenic right ventricular cardiomyopathy, although precision of estimates for arrhythmogenic right ventricular cardiomyopathy were limited. CONCLUSIONS AND RELEVANCE: In this cohort study, MVPA within the general range of guideline-based recommendations was associated with lower risk of adverse CV outcomes and similar degrees of cardiac remodeling for G+P- carriers compared to noncarriers. Findings support the appropriateness of guideline-based MVPA recommendations for G+P- carriers.

Humans

PCSK9 inhibition attenuates alcohol-induced cardiovascular dysfunction and links hepatic lipid accumulation to impaired myocardial contractile reserve.

Excessive alcohol consumption accelerates cardiovascular aging by promoting oxidative stress, inflammation, lipid dysregulation, fibrotic remodeling, and loss of ventricular-vascular reserve. PCSK9, a key regulator of cholesterol metabolism, has emerged as a mediator of age-related cardiovascular dysfunction and alcohol-associated liver and neurovascular injury. We investigated whether PCSK9 inhibition protects against alcohol-induced cardiovascular dysfunction and associated cardiac-hepatic injury in rats. Male Sprague-Dawley rats were assigned to pair-fed control or 35% ethanol liquid diet groups and treated weekly with subcutaneous alirocumab, 50&#xa0;mg/kg, or vehicle for 6&#xa0;weeks. Blood alcohol and cholesterol levels were measured; cardiac function was assessed by echocardiography and invasive pressure-volume analysis; and myocardial, vascular, and hepatic injury markers were quantified. Alirocumab reduced total cholesterol in both pair-fed and ethanol-fed rats without altering blood alcohol levels. Chronic ethanol exposure impaired systolic performance, myocardial contractile reserve, diastolic relaxation, and ventricular-arterial coupling, as reflected by reduced stroke volume, cardiac output, ejection fraction, fractional area change, dP/dtmax, stroke work, ESPVR slope, PRSW, and dP/dtmax-EDV, together with abnormalities in TauWeiss and dP/dtmin. PCSK9 inhibition markedly attenuated these functional deficits. Alirocumab also reduced ethanol-induced myocardial and vascular malondialdehyde accumulation and suppressed myocardial induction of NOX4, LOX1, iNOS, TNF-&#x3b1;, ANP, and profibrotic markers. Ethanol increased myocardial fibrosis, hepatic triglyceride accumulation, perilipin-2 staining, and mild hepatic fibrotic remodeling, all of which were attenuated by alirocumab. Liver triglyceride content correlated inversely with ESPVR slope and PRSW. These findings identify PCSK9 as a potential therapeutic target for alcohol-related cardiovascular dysfunction and associated cardiac-hepatic injury.

Accelerated aging

Non-telomeric function deficiency of TERT enhances pressure overload-induced mouse cardiac remodeling by activation of CNBP-mediated THBS3/ITGB1 pathway.

Recent studies show that telomerase reverse transcriptase (TERT) possesses important new biological functions in gene transcription regulation, signal transduction, tumorigenesis, vascular development and mitochondrial DNA protection independent of the maintenance of telomere length. In this study we investigated the role and mechanisms of TERT in regulating the gene expression and signal transduction during pressure overload-induced cardiac remodeling. The first-generation TERT knockout (Tert-/-) and wild-type littermate control (Tert+/+) male mice were subjected to transverse aortic constriction (TAC) surgery to establish a pressure overload-induced cardiac remodeling model. We showed that pressure overload significantly increased TERT expression in the hearts at 8 weeks after TAC, whereas TERT deficiency remarkably exacerbated pressure overload-induced cardiac dysfunction, cardiac hypertrophy and fibrosis, and reduced the survival rate of the mice. In contrast, TERT overexpression reversed phenylephrine (PE)-stimulated cardiomyocyte hypertrophy and fibrosis in neonatal rat ventricular myocytes (NRVMs). Ttranscriptomic and proteomic analyses revealed that extracellular matrix (ECM)-receptor interaction was a key Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway regulated by TERT in hemodynamic overload-induced cardiac remodeling. TERT knockdown greatly enhanced, while TERT overexpression inhibited the activation of the THBS3/ITGB1 signaling pathway, in which transcription factor cellular nucleic acid-binding protein (CNBP) played a pivotal mediating role by interacting with TERT. In conclusion, the non-telomeric function of TERT in gene transcription regulation and signaling transduction plays an important role during pressure overload-induced myocardial remodeling via modulating CNBP-mediated THBS3/ITGB1 signaling pathway, which provides new targets and strategies for the prevention and treatment of pressure overload-induced cardiac remodeling.

Animals

Cardiac remodelling and dysfunction in cancer patients receiving cardiotoxic therapies: proteomic and metabolomic profiling.

BACKGROUND AND AIMS: The objective of this study was to define the relationships between the circulating proteome and metabolome with cardiac structure and function in patients with breast cancer receiving cardiotoxic therapies. METHODS: Proteomics and metabolomics profiling was performed in a longitudinal, prospective cohort study of breast cancer patients receiving anthracyclines and/or trastuzumab, using the Olink Explore 3072 platform and rapid liquid chromatography-mass spectrometry, respectively. Multivariable linear mixed-effect models evaluated the contemporaneous (same visit) and lagged (subsequent visit) associations between repeated measures of individual proteins or metabolites with quantitative echocardiographic measures of cardiac structure [left ventricular (LV) mass and left atrial volume index] and function [LV ejection fraction (LVEF), longitudinal and circumferential strain, E/e', and ventricular-arterial coupling]. Cox regression and pathway enrichment analyses were conducted for biomarkers demonstrating significant associations with cardiac function. RESULTS: Across 547 breast cancer participants (median age 50 years), 203 unique proteins and 16 unique metabolites were significantly associated with measures of cardiac structure and function in contemporaneous and lagged analyses. Notably, cathepsin C was associated with LVEF [false discovery rate (FDR), P = .017], longitudinal strain (FDR, P = .046), left atrial volume index (FDR, P = .035), and incident cardiac dysfunction, defined by an LVEF decline &#x2265;10% to <50% (hazard ratio .61, 95% confidence interval .41, .90). The 147 proteins associated with cardiac function were enriched in biological processes reflective of protein deubiquitination, protein modification by small protein removal, macromolecule catabolic processes, and global metabolic pathways. Individual metabolites significantly associated with cardiac function (LVEF, longitudinal strain) included n-acetylglutamine, aspartic acid, acetylasparagine, alanyl-alanine, and prolyl-glycine (FDR, P-value < .001), and belonged to amino acids and derivatives and peptides. CONCLUSIONS: These findings provide translational insights into cancer therapy-related cardiac dysfunction and remodelling and identify potential new biomarkers of cardiotoxicity. There is an important need for validation of these findings and a deeper understanding of the biology of these biomarkers.

Humans

New Genetic Loci Implicated in Cardiac Morphology and Function Using Three-Dimensional Population Phenotyping.

BACKGROUND: Cardiac remodeling occurs in the mature heart and is a cascade of adaptations in response to stress, which are primed in early life. A key question remains as to the processes that regulate the geometry and motion of the heart and how it adapts to stress. METHODS: We performed spatially resolved phenotyping using machine learning-based analysis of cardiac magnetic resonance imaging in 47&#x2009;549 UK Biobank participants. We analyzed 16 left ventricular spatial phenotypes, including regional myocardial wall thickness and systolic strain in both circumferential and radial directions. In up to 40&#x2009;058 participants, genetic associations across the allele frequency spectrum were assessed using genome-wide association studies with imputed genotype participants, and exome-wide association studies and gene-based burden tests using whole-exome sequencing data. We integrated transcriptomic data from the GTEx project and used pathway enrichment analyses to further interpret the biological relevance of identified loci. To investigate causal relationships, we conducted Mendelian randomization analyses to evaluate the effects of blood pressure on regional cardiac traits and the effects of these traits on cardiomyopathy risk. RESULTS: We found 42 loci associated with cardiac structure and contractility, many of which reveal patterns of spatial organization in the heart. Whole-exome sequencing revealed 3 additional variants not captured by the genome-wide association study, including a missense variant in CSRP3 (minor allele frequency 0.5%). The majority of newly discovered loci are found in cardiomyopathy-associated genes, suggesting that they regulate spatially distinct patterns of remodeling in the left ventricle in an adult population. Our causal analysis also found regional modulation of blood pressure on cardiac wall thickness and strain. CONCLUSIONS: These findings provide a comprehensive description of the pathways that orchestrate heart development and cardiac remodeling. These data highlight the role that cardiomyopathy-associated genes have on the regulation of spatial adaptations in those without known disease.

Humans

Nuclear Proteome Map of Mouse Heart Chambers.

Heart specialization involves nuclear programs; however, chamber-specific regulation of the nuclear proteome landscape remains unknown. In this study, we isolated the nucleus from four major anatomical regions of healthy mouse heart (fresh) and employed quantitative mass spectrometry-based proteomics to construct a comprehensive nuclear proteome landscape of left ventricle (LV, 2403 proteins), right ventricle (RV, 2242 proteins), left atrium (LA, 2368 proteins), and right atrium (RA, 1816 proteins). This led to the discovery of nuclear regional proteome signatures (ventricular signature, 297 proteins; atrial signature, 183 proteins) associated with oxidative metabolism and redox regulation, ferroptosis, extracellular-matrix remodeling, SUMO- and stress-responsive control and transcriptional regulation. Chamber-level analyses further identify distinct nuclear features in LV (120 proteins), LA (188 proteins), and RA (72 proteins). In addition, we defined conserved core nuclear proteome (230 proteins) shared across all anatomical regions, enriched for transcription-regulator complexes, nucleolar/ribosome-associated, RNA-processing, and chromatin-organization components. Within this core network, we report 78 transcription factors/co-factors and select nuclear, chromatin and RNA export-associated proteins, including 29 specific factors (e.g., Alpk3, Rbm14, Arglu1, Hmgb1, Myef2, Sf1) associated with the heart. Regionally, we verified spatial localization in heart of H2ac21 and Sun2 in LA and Ptbp2 in LV by immunofluorescence. This study provides insights into the chamber-resolved view of the nuclear proteome in the heart, establishes a framework for linking nuclear proteomic signatures to atrial and ventricular biology, unique features of the heart nuclear proteome landscape relative to other organs, and a baseline for studying nuclear remodeling in cardiac pathophysiology.

Animals

Early Cardiomyopathy in Prediabetic NDPK-B-Deficient Mice Is Associated with Remodeling of the Mitochondrial O-GlcNAc Proteome.

Diabetic cardiomyopathy (DCM) is characterized by myocardial remodeling that may already be evident during prediabetes, yet the molecular alterations accompanying these early changes remain poorly understood. The present study examined mouse models of Nucleoside diphosphate kinase B (NDPK-B)-deficient prediabetes and streptozotocin-induced diabetes using O-GlcNAc-associated proteomic profiling to define stage-specific molecular alterations during the progression from prediabetic to diabetic cardiomyopathy. Both models exhibited increased left ventricular extracellular matrix deposition and impaired diastolic function, together with activation of the hexosamine biosynthesis pathway. Profiling of O-GlcNAc-associated proteins uncovered extensive remodeling of the mitochondrial proteome already at the prediabetic stage, with respiratory complex I among the most prominently altered targets, alongside changes in substrate metabolism and inflammatory signaling. In overt DCM, the putative O-GlcNAc proteomic profile was associated with a shift toward wider lipid-dependent metabolic reprogramming and remodeling of mitochondrial proteins. These findings identify early remodeling of the mitochondrial O-GlcNAc-associated proteome as a molecular signature of prediabetic cardiomyopathy and highlight respiratory complex I proteins as candidate targets for future mechanistic investigations.

Animals

A reproducible computational transcriptomic framework for cell-type-resolved fibroinflammatory-AKT remodeling in human heart failure.

BACKGROUND: Human heart failure involves multicellular transcriptional remodeling, but public transcriptomic studies often remain disconnected from cell-type localization and perturbational interpretation. METHODS: We developed a reproducible computational workflow integrating human left-ventricular bulk transcriptomes, donor-level cell-type pseudobulk results from a human heart-failure single-cell/single-nucleus atlas, external snRNA-seq support, curated module scoring, focused ligand-receptor prioritization and LINCS/L1000 perturbational matching. RESULTS: Cross-cohort analysis identified 14,358 same-direction HF-associated genes, including 1633 replicated HF-up and 785 replicated HF-down genes. Donor-level pseudobulk analysis localized disease remodeling to cardiomyocyte, fibroblast and myeloid compartments. Activated fibroblast and inflammatory myeloid programs defined a fibroinflammatory remodeling axis connected to context-dependent AKT-associated transcriptional shifts. External snRNA-seq support was strongest for fibroblast activation and AKT-associated remodeling, with etiology-dependent heterogeneity across validation resources. L1000FWD screening prioritized safety-aware perturbational hypotheses, including glimepiride and simvastatin as interpretable candidates requiring experimental validation. CONCLUSIONS: This study provides a computational transcriptomic framework linking reproducible human HF signatures, cell-type-resolved fibroinflammatory remodeling and perturbational genomic prioritization without claiming drug efficacy or AKT causality.

Humans

Horse model of spontaneous atrial fibrillation share proteomic changes with humans.

Horses and humans are among the few mammals susceptible to spontaneous atrial fibrillation (AF), both suffering from high recurrence rates after treatment. Treatment resistance is often attributed to progressive atrial remodeling, but current treatment options fail to effectively address this aspect. Here, we introduce a novel horse model of spontaneous AF to investigate the biological pathway changes in early stages of the disease. Through data-independent acquisition mass spectrometry on biopsies from the right and left atrium and left ventricular chamber of horses with early-stage persistent AF (n&#x2009;=&#x2009;8) and controls (n&#x2009;=&#x2009;8), we identify several differentially regulated proteins across all three chambers. Pathway enrichment analyses and histological stainings highlight a significant role of atrial extracellular matrix (ECM) remodeling in early AF. Other key proteomic changes relate to metabolism, contractility, and protein-folding, and overlap with findings from publicly available human datasets. Our results demonstrate that horses and humans share several AF-related proteomic changes, providing translational insights into the early atrial remodeling processes that are likely to contribute to treatment resistance. These protein-level changes could serve as biomarkers or pharmacological targets for preventing AF-associated atrial remodeling and improve treatment outcomes across species.

Atrial Fibrillation

Developmental genetic determinants of the human cerebrospinal fluid-ventricular system.

Primary enlargement of the cerebrospinal fluid (CSF)-filled brain ventricles, known as congenital cerebral ventriculomegaly (CCV), is a hallmark of congenital hydrocephalus. CCV is also enigmatically but frequently associated with autism and other neurodevelopmental disorders. To gain insight into the developmental genetic regulation of the human CSF-ventricular system, we conducted an integrated, multiomic study of about 2700 trio-based exomes from patients with primary CCV. We found that about 25% of cases were associated with rare, damaging de novo variants in mutation-intolerant genes, many of which are linked to other dominant Mendelian disorders. Thirty-five exome-wide significant CCV genes and dozens of other high-confidence CCV genes converged on pathways involved in ATP-dependent Brahma-related gene 1/Brahma-associated factor chromatin remodeling, histone H3 lysine 4 methylation, and phosphoinositide 3-kinase signaling. Knockout of selected CCV genes in mouse models supported that de novo variants in CCV genes caused ventriculomegaly by impairing both CSF dynamics and cortical cytoarchitecture through dysregulation of neuroprogenitor cell growth and maturation in the ventricular and subventricular zones. These findings indicated that genetic and epigenetic programs coordinate the "hand-in-glove" development of the CSF-ventricular system with that of the cerebral cortex and establish a genetic connection between CCV and neurodevelopmental disorders, potentially explaining why some patients with hydrocephalus continue to exhibit CCV and neurodevelopmental disorders despite CSF shunting. We suggest that combined brain imaging and whole-exome sequencing could enable early detection of, and intervention for, autism and other neurodevelopmental disorders.

Humans

Distinct Effects of Rap1 Subtype A GTPase Deficiency on the Male Mouse Heart.

This study utilized a genetically engineered mouse model deficient in the small GTPase Rap1A (knockout/Rap1A-null) to understand the biological role of Rap1A in the heart. We examined differential protein expression in the left ventricle of Rap1A-null versus wild-type control C57BL/6 male mice (~5 months) using proteomics (nanoLC-MS/MS quantitative analysis), and in the whole heart of aged male mice (~16 months) using MAL-DI-TOF/TOF mass spectrometry. Additionally, we used an experimental model of acute cardiovascular stress and assessed the impact on heart tissue histology, gene expression and mortality risk. Rap1A-deficient hearts showed reduced size and reduced heart and left ventricular weights. Significantly reduced gene expression of extracellular matrix collagen type I and collagen type III was present under baseline and cardiovascular stress conditions. Assessment of the proteomic profile identified a crucial role of Rap1A in promoting healthy ventricular myocardium, as its deficiency exhibited increased impact on cytoskeletal, mitochondrial, metabolic and contractile protein expression in young and aged mice. In young Rap1A-deficient mice, overrepresentation analysis revealed markers myosin heavy chain 7 (&#x3b2;-MHC) and alpha-actinin-2 (&#x3b1;-actinin-2) associated with cardiomyopathies, and upon cardiac stress, showed mortality risk compared to controls. Altogether, these findings provide important insights into the role of Rap1A in cardiac structure and remodeling under basal and stress conditions in male mice.

Animals

Murine metabolic HFpEF is associated with altered mitochondrial substrate handling and S-nitrosylation remodeling.

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous condition with incompletely defined myocardial mechanisms. Here, using a two-hit murine model of cardiometabolic HFpEF induced by high-fat diet and endothelial nitric oxide synthase inhibition, we define a mitochondrial metabolic phenotype characterized by altered substrate handling, redox stress, and S-nitrosylation remodeling. While global proteomic changes were modest, metabolomic profiling revealed selective remodeling of tricarboxylic acid cycle intermediates, increased dicarboxylic acids, and altered redox-associated metabolites, consistent with mitochondrial metabolic and redox imbalance in this experimental setting. S-nitrosylation proteomics demonstrated a highly organized and bidirectional remodeling pattern affecting proteins involved in fatty acid/lipid metabolism, carbohydrate metabolism, mitochondrial energy metabolism, amino acid and organic acid metabolism, nucleotide/co-factor metabolism, and redox defense. Stable&#xa0;isotope tracing showed reduced glucose-derived and increased palmitate-derived acetyl-CoA in HFpEF, whereas Na-&#x3b2;HB reduced palmitate contribution and increased &#x3b2;HB-derived acetyl-CoA without restoring glucose contribution, indicating substrate redistribution and preserved ketone oxidation. Na-&#x3b2;HB supplementation increased oligomycin-sensitive respiration in freshly prepared left ventricular tissue, partially normalized selected TCA-cycle intermediates, reduced mitochondrial ROS and the NADH/NAD+ ratio, restored the GSH/GSSG ratio, and improved diastolic function without altering ejection fraction. Together, these findings define a redox-sensitive mitochondrial metabolic state in the HFD/l-NAME model and identify ketone supplementation as a partial metabolic rescue strategy in this context. At the same time, these findings highlight an important limitation of the murine HFD/l-NAME model, which should be interpreted as an experimental system for studying high-fat-induced cardiometabolic stress rather than as a metabolic equivalent of human HFpEF.

Animals

Spherical microparticles in human myocardium: an ultrastructural study.

Clusters of spherical microparticles (SMP) that averaged 500 A in diameter and were composed of dense cores surrounded by single trilaminar membranes were found in operatively obtained myocardial biopsies from 29 of 70 patients with various types of heart diseases including: left atrial myocardium (14 patients) and right atrial myocardium (four patients) of 14 patients with mitral valvular disease; left ventricular myocardium of three of 16 patients with aortic valvular disease, three of 16 patients with hypertrophic cardiomyopathy, and two of four patients with combined mitral and aortic valvular disease; and crista supraventricularis muscle of seven of 20 patients with congenital heart diseases associated with muscular obstruction to right ventricular outflow. SMP were consistently associated with interstitial fibrosis and with degeneration of the muscle cells. SMP occurred along the outer surfaces on the sides and free ends of muscle cells in areas of fibrosis, in the widened spaces between membranes of partially dissociated intercellular junctions, and within cytoplasmic vesicles considered to be phagocytic. SMP frequently were joined together by minute nexuses that were structurally identical with those forming parts of intercellular junctions of muscle cells. Evidence is presented to show that SMP occur commonly in tissues other than myocardium. It is concluded that SMP form in the heart as part of a process that mediates the remodeling of cellular surfaces, especially those of intercellular junctions undergoing dissociation.

Cardiomegaly

Severe Suprasystemic Refractory Pulmonary Hypertension in a Neonate with St&#xfc;ve-Wiedemann Syndrome Associated with Biallelic LIFR Variants: Molecular Insights and a Neonatal Case Report.

St&#xfc;ve-Wiedemann syndrome (SWS) is an ultra-rare autosomal recessive skeletal dysplasia caused by loss-of-function variants in the leukemia inhibitory factor receptor (LIFR) gene. While characterized by bone deformities and dysautonomia, severe persistent pulmonary hypertension of the newborn (PPHN) significantly contributes to high early mortality. We report a neonate with genetically confirmed SWS who presented with severe, suprasystemic PPHN refractory to standard pulmonary vasodilators, including inhaled nitric oxide. This case provides a detailed longitudinal hemodynamic characterization of severe suprasystemic PPHN in genetically confirmed SWS, including serial assessment of pulmonary pressures, shunt direction, and right ventricular function during treatment. Rather than identifying PPHN as a novel manifestation of SWS, it extends the phenotypic and hemodynamic characterization of pulmonary vascular involvement in this rare disorder.

Humans