Circulation: Heart Failure

Background: Adults with congenital heart disease (ACHD) represent a rapidly expanding population with evolving mortality patterns. Despite improved survival, excess mortality persists. Objective: To evaluate the incidence, causes, and predictors of mortality in a contemporary ACHD cohort. Methods: We performed a retrospective cohort study of adults (?18 years) first evaluated at Mayo Clinic from 2002?2023. Baseline clinical, imaging, and electrocardiographic data were analyzed. Vital status was determined using institutional records and the Accurint national mortality database. Kaplan-Meier analysis and Cox proportional hazard models were used to evaluate mortality and identify independent predictors of mortality Results: A total of 7,678 ACHD patients were included, with median age of 36.8 years and median follow-up of 11.4 years. During 78,768 patient-years of follow-up, 1,116 patients died (median age at death 57.2 years), corresponding to an annual mortality rate of 1.4%. The cumulative rate of all-cause mortality at 5, 10, 15, and 20 years was 6.9%, 12.0%, 19.0%, and 26.2%, respectively. When stratified by CHD complexity, the annual death rate in patients with severe CHD (2.4%/year) was twice that of patients with moderate or mild CHD (both 1.2%/year). Older age and ACHD subtypes, specifically, cyanotic heart disease (HR 3.9, 95% CI 2.9?5.3) and Fontan physiology (HR 3.2, 95% CI 2.3?4.4), were strongly associated with increased mortality. Additional independent predictors included male sex, ventricular dysfunction, advanced NYHA class, prior heart failure hospitalization, hypertension, smoking, coronary artery disease, renal dysfunction, and abnormal hemoglobin levels. Cardiovascular causes accounted for 57.7% of deaths with known etiology, predominantly heart failure (48.9%) and sudden cardiac death (21.9%), while non-cardiovascular causes were driven mainly by infection and malignancy. Conclusions: In this large contemporary ACHD cohort, mortality was driven by ventricular dysfunction, heart failure, and systemic end-organ involvement in addition to the underlying congenital anatomy. Both cardiovascular and non-cardiovascular causes contributed significantly to mortality. These findings underscore the need for comprehensive multidisciplinary ACHD care focused on early recognition of cardiac functional decline, management of acquired comorbidities, and end-organ dysfunction.

Background Hospitalizations and mortality due to heart failure (HF) are rising in rural areas. However, inpatient outcomes for young adults with HF are not well understood. We aimed to compare in-hospital mortality, advanced procedure utilization, length of stay, and total charges among rural and urban HF patients ages 18-45. Methods We analyzed hospitalizations from the National Inpatient Sample (2016-2022), categorizing discharges as rural (National Center for Health Statistics [NCHS] 5-6), small and medium metropolitan (NCHS 3-4), and urban (NCHS 1-2). Generalized estimating equations were used to model outcomes and adjust for demographics, comorbidities, and hospital characteristics. Outcomes are reported as adjusted rate (aIRRs) or risk ratios (aRRs) with 95% confidence intervals. Results Among 79,258 HF hospitalizations among young adults, 45,075 and 10,722 were for patients from urban and rural areas, respectively. Rural patients had higher rates of in-hospital mortality (1.6% vs. 1.2%; aIRR = 1.28, 95% CI = 1.05, 1.56, p = 0.043), advanced cardiac procedure utilization (15.0% vs. 14.8%; aIRR = 1.19, 95% CI = 1.11, 1.28, p < 0.001), and longer hospital stays (aIRR = 1.10, 95% CI = 1.05, 1.14, p = 0.003). Small and medium metropolitan residents had similar outcomes to urban residents. In interaction analyses, the association between rural-urban residence and mortality differed by race (pint = 0.003) and payer type (pint < 0.001). Conclusions Young adults in rural areas may be prone to poor outcomes following hospitalization for HF. Strategies to identify rural adults at risk for HF and provide affordable and timely care may improve disparities.

Background: Blood volume (BV) in patients with chronic heart failure (HF) is characterized by heterogeneity in volume profiles; one profile being "normal BV". While overall intravascular volume may be considered normal clinically, the relative contributions of red blood cell (RBC) mass and plasma volume (PV) may not be. Objective: Assess how normal is a "normal BV" based on quantitative measures of RBC mass and PV. Methods: Retrospective analysis was undertaken in 395 patients with Class II-III HF. BV was quantitated using indicator-dilution methodology. Cohort was stratified by normal and hypervolemic BV. Results: Of the cohort, 31% (123/395) demonstrated normal total BV and 62% (244/395) hypervolemic BV. Of patients with "normal BV", 36% (44/123) demonstrated normal RBC mass and 60% normal PV (74/123). Importantly, 60% (74/123) demonstrated a deficit in RBC mass (true anemia), while a low hemoglobin (<12 g/dL) was present in just 29% (36/123). An excess in RBC mass (erythrocytosis) in 4% (5/123). Notably, true normal BV (i.e., normal RBC mass and normal PV) was observed in only 30% (37/123) of patients with an overall "normal" intravascular volume. Conclusions: Findings reveal that "normal BV" can be misleading by concealing substantial variability in RBC mass (including unrecognized anemia and erythrocytosis) as well as different degrees of PV expansion and contraction. An actual normal BV was identified in a minority of "normal BV" patients. This underscores the importance of looking beyond overall "normal BV" to the contributing elements of RBC mass and PV with significant implications for patient management and outcomes.

Heart failure (HF) is a leading cause of morbidity and mortality. We conducted multi-ancestry genome-wide association studies of 345,687 HF cases (4,468,166 individuals), and 47,192 and 46,934 cases of HF with preserved (HFpEF) and reduced ejection fraction (HFrEF), respectively, integrating plasma proteomics and multi-tissue transcriptomics to identify druggable targets. Across HF, HFrEF, and HFpEF, we identified 383 loci (166 novel) and 568 genes (375 novel). Eleven novel genes are targets of approved or investigational cardiovascular therapies, supporting indication expansion of aldosterone synthase inhibitors (CYP11B2) and type-II activin receptor antagonists (ACVR2A) to HF. Six cardiomyopathy genes were novel for HF and associated with cardiac structure and function. We identified nearly 100 genes involved in food intake and energy expenditure; metabolism of fatty acids, glucose, and branched-chain amino acids; and mitochondrial proteome, sustaining myocardial energy production. Our findings highlight the primordial role of metabolic pathways and adipokines as therapeutic targets for HF management.

Background: A dose finding trial evaluated safety and adherence for pre-cardiac surgery administration of sodium valproate. Integrated multi-omics analyses of myocardium were used to characterise mechanisms underlying the treatment effects. Methods: Adults undergoing cardiac surgery were randomised 1:1:1:1 with concealed allocation to no treatment (Controls), sodium valproate 15mg/kg/day for 1-2 weeks, 15mg/kg/day for 4-6 weeks, or 25mg/kg/day for 4-6 weeks pre-surgery. The primary analysis evaluated adherence and toxicity. Myocardial injury was defined by high sensitivity serum troponin at 24 hours post-surgery. Single-nucleus Assay for Transposase-Accessible Chromatin with sequencing (snATACseq) and single nuclei RNA sequencing (snRNAseq) of myocardial biopsies collected at surgery assessed treatment effects on chromatin accessibility and gene expression. Candidate mechanisms were validated in in vitro. Results: The analysis cohort included 42 participants enrolled between January 2020 and August 2024. Non-compliance (38%) was highest with longer and higher dosing. Sodium valproate 15mg/kg/day for 1-2 weeks had the highest levels of complete treatment adherence (70%), with 20% experiencing moderate/severe drug related adverse effects. An as-treated analyses demonstrated reductions in troponin release in participants receiving Valproate[&le;]14 days. Myocardial biopsies from trial participants demonstrated activation of hormetic p53 and Akt-GSK-3{beta} ferroptosis protection pathways. Treatment effects were not attributable to chromatin accessibility. Treatment >14 days resulted in a heart failure phenotype with suppression of ferroptosis protection pathways, endothelial mesenchymal transition, and increased myocardial injury. Conclusions: Sodium valproate 15mg/kg/day for [&le;]14 days pre-surgery is well tolerated in adults awaiting cardiac surgery. This treatment was associated with upregulation of ferroptosis protection pathways and reductions in myocardial injury.

Background Targeted pharmacologic therapies for transthyretin amyloid cardiomyopathy (ATTR-CM) improve survival; however, their effects on cardiac structural parameters remain incompletely defined. Objectives To evaluate the pooled effects of disease-modifying therapies for ATTR-CM on echocardiographic structural parameters. Methods In accordance with PRISMA guidelines, we performed a systematic review and meta-analysis of randomized controlled trials and observational studies published through March 2025 assessing transthyretin stabilizers and RNA-silencing therapies in adults with cardiac amyloidosis. Outcomes included changes in global longitudinal strain (GLS), left ventricular ejection fraction (LVEF), interventricular septal (IVS) thickness, left ventricular mass, stroke volume, E/e? ratio, and LV end-diastolic volume. Pooled between-group mean differences were calculated using random-effects models. Sensitivity analyses were performed. Results Eighteen studies (11 randomized, 7 observational) encompassing 3,646 patients were included. Compared with control, drug therapy was associated with attenuation of GLS decline (mean difference [MD] -0.69%; 95% CI -1.10 to -0.29; P<0.001) and preservation of LVEF (MD 1.62%; 95% CI 0.73 to 2.51; P<0.001). Treatment was also associated with reduced worsening of E/e? ratio, and preservation of stroke volume. No significant between-group differences were observed for IVS thickness, LV mass and LV end-diastolic volume. Within-group analyses showed no change in echocardiographic parameters between baseline and follow-up in treated patients, in contrast to significant worsening in the control cohort. Conclusions Disease-modifying therapies for ATTR-CM are associated with stabilization and attenuated progression of cardiac remodeling rather than reversal of structural abnormalities.

Background Adults with a systemic right ventricle (sRV) due to congenitally corrected transposition of the great arteries (ccTGA) or atrial switch repair for d-transposition of the great arteries (d-TGA) experience substantial physiologic and psychosocial morbidity. Relationships among exercise capacity, sRV function, and mental health remain incompletely characterized. Objectives To characterize relationships among anatomic subtype, exercise capacity, sRV function, and mental health in adults with sRV physiology. Methods We performed a retrospective cohort study of adults with ccTGA or d-TGA (Mustard/Senning) followed at a tertiary Adult Congenital Heart Disease program from 2000 to 2025. Clinical, imaging, cardiopulmonary exercise testing, and patient-reported data were obtained from electronic health records. Mental health diagnoses were identified from clinical documentation. Functional status was assessed using NYHA class and the Kansas City Cardiomyopathy Questionnaire (KCCQ-12). Results Among 137 adults (ccTGA, n = 51; d-TGA, n = 86), percent-predicted peak VO2 was lower in d-TGA than ccTGA (60% vs 74%, p < 0.001), as was sRV systolic function (41 +/- 11% vs 47 +/- 10%, p < 0.01). Anxiety or depression was more common in d-TGA (46% vs 25%, p < 0.05). Across the cohort, anxiety or depression was associated with lower exercise capacity, worse NYHA functional class, and lower KCCQ scores. Conclusions Adults with d-TGA following atrial switch have lower exercise capacity, reduced sRV systolic function, and greater mental health burden than adults with ccTGA. These findings support integrated assessment of physiologic performance, functional status, and mental health in adults with sRV physiology.

Background: Obstructive hypertrophic cardiomyopathy (oHCM) causes substantial symptom burden and impaired functional capacity. Mavacamten has emerged as a targeted pharmacologic treatment, whereas alcohol septal ablation (ASA) is an established septal reduction therapy (SRT). Direct comparative real-world data remain limited. Methods: In this propensity-controlled observational study, longitudinal registry data from Heidelberg University Hospital were analyzed. Consecutive adults with oHCM, NYHA class ?II symptoms, and a maximum LVOT gradient ?50 mmHg treated with mavacamten or ASA were included. The cohort comprised 107 ASA- and 113 mavacamten-treated patients. Follow-up was performed at 6 and 12 months. The primary endpoint was a composite adverse clinical outcome including cardiovascular death, heart failure hospitalization, SRT, heart transplantation, ventricular assist device implantation, permanent pacemaker implantation for third-degree atrioventricular block, or decline in left ventricular ejection fraction to <40%. Results: Both treatments showed significant improvement in NYHA class and LVOT gradient reduction over 12 months. Mean LVOT gradient decreased from 100.3 to 44.2 mmHg after ASA and from 85.7 to 18.4 mmHg with mavacamten at 12 months (both p<0.001). Between-group differences were not significant at 6 months, whereas residual LVOT gradient was lower with mavacamten at 12 months (p=0.004). NT-proBNP declined in both groups and was lower with mavacamten at both follow-up visits (both p<0.001). Third-degree atrioventricular block occurred more frequently after ASA (6.5% vs 0%, p=0.002). The composite endpoint occurred in 13 ASA- (12.1%) and 4 mavacamten-treated patients (3.5%) (p=0.003), with higher 1-year event-free survival in the mavacamten group (HR 0.19; 95%-CI 0.06-0.60; p=0.001). Conclusions: In this real-world comparative study, both ASA and mavacamten improved symptoms and LVOT obstruction in oHCM. Mavacamten was associated with a more favorable short-term hemodynamic and safety profile at 12 months.

Background Exercise intolerance is common in adults with repaired tetralogy of Fallot (rTOF) despite preserved left ventricular ejection fraction (LVEF [&ge;]50%). Whether reduced exercise capacity is associated with early cardiac remodeling remains unclear. Objectives To determine whether reduced exercise capacity in rTOF with preserved LVEF is associated with diastolic dysfunction, atrial remodeling, right ventricular (RV) dysfunction, and myocardial fibrosis. Methods We retrospectively studied adults with rTOF and preserved LVEF who underwent cardiopulmonary exercise testing (CPET) and transthoracic echocardiography (TTE) and/or cardiac MRI (CMR) within 18 months. Exercise capacity was assessed by percent-predicted peak VO2 (ppVO2). Diastolic function and atrial remodeling were evaluated by TTE, and CMR assessed RV function and myocardial fibrosis. Results Reduced exercise capacity was associated with larger left atrial volume index (LAVI; p < 0.001), elevated E/e' and reduced e' velocity (both p < 0.05), and reduced RV systolic function (p < 0.001). LAVI correlated inversely with ppVO2 ({rho} = -0.27, p = 0.003). A composite diastolic dysfunction score showed a graded relationship with exercise capacity, with patients exhibiting [&ge;]2 abnormalities having lower ppVO2 than those with [&le;]1 abnormality (both p < 0.01). In contrast, pulmonary regurgitation (PR) severity and myocardial fibrosis by late gadolinium enhancement (LGE) were not associated with exercise capacity. Conclusions In adults with rTOF and preserved LVEF, reduced exercise capacity is associated with atrial remodeling, diastolic dysfunction, and RV dysfunction despite the absence of overt myocardial fibrosis. This suggests that multimodal imaging identifies an imaging-defined cardiac remodeling phenotype associated with early functional impairment.

Heart Failure with Preserved Ejection Fraction (HFpEF) is more prevalent in females and is associated with altered cardiac glucose metabolism. However, whether these metabolic alterations are conserved across sexes and between humans and widely used cardiometabolic mouse model of HFpEF remains unclear. We investigated species-, sex-, and ventricle-specific conserved and divergent features of HFpEF. Cardiometabolic HFpEF was induced in mice using the 'two-hit' model (high-fat diet + L-NAME), followed by assessment of cardiac function, RNA sequencing, and protein expression in the right (RV) and left (LV) ventricles. Published human HFpEF RV and LV RNA-seq datasets were reanalyzed and compared with our mouse data. Only male HFpEF mice recapitulated human phenotype of increased RV GLUT1 protein. In contrast, mouse GLUT1 was downregulated in RV of females and in the LV of both sexes, whereas GLUT4 protein remained unchanged. Cardiac PDK4 transcript and protein levels increased in the RV and LV of mice. Conversely, human PDK4 mRNA levels were reduced in the RV with HFpEF and unchanged in LV. Cardiac transcriptome analysis in mice revealed extensive alterations in LV, particularly in females, with enrichment of inflammatory pathways. Cross-species analysis demonstrated greater conservation of HFpEF-associated signatures in the RV than the LV. Furthermore, number of differentially expressed transcripts in human LV increased substantially after excluding patients with atrial fibrillation or diabetes. Overall, the RV of the 'two-hit' model more closely resembles human HFpEF. The cardiac transcriptome reflects sexual dimorphism, and conserved signatures are primarily associated with metabolic alteration, mitochondrial dysfunction, and cellular stress.

Background: Heart failure (HF) is classified by ejection fraction: reduced EF (<40%) is HFrEF and preserved EF (>50%) is HFpEF. Unlike HFrEF, no therapeutic agent improves mortality in HFpEF. The molecular mechanism that produces HFpEF is not completely understood, but the cascade of pathology that produces HFpEF is thought to begin with changes in vascular reactivity, including a decrease in NO mediated vasodilatation, which coupled with subsequent changes in contractility, energetics and coronary blood flow produce HFpEF. If abnormal vascular reactivity is the initial step in the pathological cascade that produces HFpEF, restoring and/or improving vascular reactivity could represent a novel treatment strategy. Vascular reactivity is primarily regulated by myosin light chain phosphatase, which has catalytic, myosin targeting (MYPT1) and 20kDa subunits. Alternative mRNA splicing of exon24 (E24) of the MYPT1 transcript produces MYPT1 isoforms that differ by the presence or absence of a COOH-terminal leucine zipper (LZ+/LZ-); E24 exclusion produces an NO responsive LZ+ MYPT1, while E24 inclusion produces an NO unresponsive LZ- MYPT. Methods: We used the mouse two-hit model of HFpEF (high fat diet and L-NAME) and treated mice with an antisense octo-guanidine targeting the 5' splice site of E24 (ASO-E24) to increase the expression of the NO responsive, LZ+ MYPT1 isoform in vascular smooth muscle. Invasive and noninvasive hemodynamics were used to determine LV function. Results: Compared to mice with HFpEF, ASO-E24 treatment maintains LZ+ MYPT1 expression (4.7{+/-}0.7au v 1.0{+/-}0.4au v 2.0{+/-}0.4au, control v HFpEF v ASO-E24 Rx, p<0.05), improves diastolic function; LVEDP (10{+/-}1mmHg v 20{+/-}4mmHg v 14{+/-}3mmHg, p<0.05), dP/dtmin (-8000{+/-}300mmHg/s v 6000{+/-}500mmHg/s v 8500{+/-}700mmHg/s, p<0.05), both early (E; 0.60{+/-}0.05m/s v 0.42{+/-}0.06m/s v 0.64{+/-}0.06m/s, p<0.05) and late diastolic filling (A; 0.38{+/-}0.03m/s v 0.24{+/-}0.02m/s v 0.47{+/-}0.04m/s, p<0.050 and also prevents the increase in lung weight (167{+/-}5g v 175{+/-}7g v 166{+/-}5g, p<0.05). Further, mice treated with ASO-E24 maintained normal relaxation to 8Br-cGMP (65{+/-}5% v 44{+/-}9% v 72{+/-}9%, p=0.05). Conclusion: These data demonstrate that maintaining normal LZ+ MYPT1 expression and vascular reactivity prevent the development of HFpEF. These results are consistent with the hypothesis that abnormal vascular reactivity is the initial and primary step in the pathological cascade that produces HFpEF and ASO-E24, which is designed to preserve normal LZ+ MYPT1 expression and vascular reactivity, could represent a novel and effective treatment strategy for HFpEF.

Acute myocardial infarction (MI) is a major precursor to heart failure (HF), yet few biomarkers are routinely used to predict post-MI HF, and limited therapeutic options exist to prevent its development. Furthermore, identifying patients at extremely high risk of recurrent MI remains challenging. These gaps highlight the need for improved biomarkers, therapeutic targets, and computational approaches for risk assessment and treatment-response prediction. To address risk assessment, we developed a systems bioinformatics (SB), graph-based framework representing patient information as personalized networks and integrating omics, clinical, and molecular prior-knowledge data. Graph neural network (GNN) machine learning (ML) models were compared with conventional ML approaches. Two large-scale public plasma proteomic datasets were used to predict post-MI HF. To investigate treatment response, regression models were applied to longitudinal clinical data from >400 hospitalized patients enrolled in the EMMY trial evaluating empagliflozin. ML-driven feature selection identified proteins and clinical parameters with the greatest predictive value. The graph-based framework demonstrated strong and consistent performance across independent post-MI cohorts. GNN models outperformed conventional approaches, including generalized linear models and XGBoost, particularly when attention mechanisms were incorporated. Using biomarker panels alone, the best GNN achieved an external test AUC of 0.82, compared with 0.77 for the best conventional ML model. When biomarkers were combined with clinical and demographic variables, GNN and conventional ML models achieved AUCs of 0.80 and 0.77, respectively. Regression models also showed promise for predicting biomarker changes associated with treatment response, with the best model achieving a test RMSE of 0.56. Feature-importance analysis identified NT-proBNP (NPPB), cardiac troponins (TNNI3/TNNT2), and prior HF history as the most influential predictors, consistent with established clinical evidence. Overall, these findings support graph-based ML and regression analysis as promising approaches for improving post-MI HF risk prediction and therapeutic response and identifying clinically relevant markers.

BACKGROUND: Increased left ventricular mass (LVM) at a single time point after heart transplantation (HT) predicts future adverse outcomes. However, dynamic changes in LVM could have better biological relevance and reflect adverse graft remodeling (AGR). The prognostic significance of such serial changes has not been studied. METHODS: Using an automated, electronic health record-based institutional data infrastructure, we studied 439 HT recipients with 5,563 LVM measurements. Separate Bayesian joint models estimated the simultaneous associations of current LVM and its instantaneous rate of change with graft dysfunction (GD) and mortality. A joint-model-derived remodeling score combining patient-specific deviations in LVM and slope was dichotomized to define AGR and non-AGR groups. A mixed-effects analysis of all clinical variables was performed to assess associations with LVM both between and within patients. An independent cohort of 35 patients with 79 surveillance-biopsy RNA-sequencing samples was used to examine early stress-responsive pathways associated with the remodeling score. RESULTS: LVM declined by approximately 7 g/year after transplantation, with regression attenuating over time. Sixty patients (13.7%) had GD, and 75 (17.1%) died. Higher LVM was associated with subsequent GD (hazard ratio [HR] per 10 g, 1.14; 95% credible interval [CrI], 1.02-1.28) and mortality (HR, 1.10; 95% CrI, 1.02-1.19). A more positive LVM slope was associated with GD (HR per 1 g/year, 1.21; 95% CrI, 1.06-1.42) and with cardiac allograft vasculopathy (CAV) grade 2 or 3 (HR, 1.39; 95% Crl, 1.02-1.96). LVM regressed more slowly in the AGR group (-5.8 vs -8.4 g/year), with higher GD (21.0% vs 6.4%) and mortality (24.2% vs 10.0%). Time-updated GD was associated with subsequent death (HR, 8.12; 95% Confidence Interval [CI], 4.67-14.14). Transcriptomic analysis showed enrichment of interferon-mediated signaling and vascular endothelial activation with higher remodeling scores, whereas lower scores were associated with mitochondrial and metabolic processes, ribosome biogenesis, and pathways related to tissue repair and stress responses. CONCLUSIONS: AGR is an easily accessible imaging biomarker that reflects the changes in the allograft in response to various stressors and predicts future adverse outcomes. Discovery of molecular mechanisms of AGR could lead to novel therapies to protect the allograft from chronic rejection.

Background and AimsCardiac fibrosis is a major contributor to heart failure (HF), yet mechanisms limiting pathological fibroblast activation remain incompletely understood. We identified dysferlin (DYSF), a membrane repair protein, as highly induced in HF fibroblasts and investigated its role in regulating profibrotic responses. MethodsCardiac fibroblasts from patients with end-stage HF and unaffected donor hearts were analysed by liquid chromatography-tandem mass spectrometry and bulk RNA sequencing. Dysferlin expression was validated in independent cohorts. Selected gene/protein expression was validated using single-cell/single-nucleus RNA sequencing and multiplex immunofluorescence of human myocardium from dilated cardiomyopathy (DCM), ischaemic cardiomyopathy (ICM), acute myocardial infarction (AMI), and unaffected hearts. Functional studies were performed in human and mouse cardiac fibroblasts using siRNA-mediated silencing and TGF-{beta} stimulation, and in engineered human 3D cardiac microtissues. Fibrotic remodelling, autophagy, apoptosis, and contractile function were assessed by molecular, histological, biochemical and functional analyses. ResultsDysferlin abundance was markedly increased in HF fibroblasts. Across HF myocardium, DYSF was enriched in activated fibroblasts but largely excluded from COMP-enriched fibrotic regions, consistent with a role in restraining fibroblast state transitions. Although induced by TGF-{beta}, DYSF silencing enhanced extracellular matrix production, increased FOSL2 expression, and promoted differentiation into COMP-positive matrifibrocytes. In engineered human cardiac microtissues, DYSF silencing exacerbated fibrosis, increased apoptosis, and impaired contractility. Mechanistically, dysferlin restrained the TGF-{beta}-FOSL2-autophagy signalling axis, whereas FOSL2 suppressed DYSF expression, defining a reciprocal regulatory circuit. Silencing FOSL2 or MXRA5 increased dysferlin levels, while mRNA-protein discordance implicated S-acylation as a potential regulator of dysferlin protein abundance. ConclusionsDysferlin is a stress-inducible antifibrotic regulator that limits maladaptive fibroblast differentiation and myocardial fibrosis, thereby representing a potential therapeutic target to attenuate adverse cardiac remodelling in HF. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=122 SRC="FIGDIR/small/745492v1_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@b52f7dorg.highwire.dtl.DTLVardef@140f781org.highwire.dtl.DTLVardef@3964f5org.highwire.dtl.DTLVardef@131404_HPS_FORMAT_FIGEXP M_FIG C_FIG

Objectives: Mitral regurgitation (MR) evolution after transcatheter aortic valve replacement (TAVR) in low-flow aortic stenosis (LFAS) is poorly characterized. We evaluated MR trajectories across LFAS phenotypes, predictors of MR worsening, and associations with clinical outcomes. Methods: We retrospectively studied 614 LFAS patients undergoing TAVR: low-flow high-gradient (LFHG; n=153, 24.9%), classical low-flow low-gradient (cLFLG; n=155, 25.2%), and paradoxical low-flow low-gradient (pLFLG; n=306, 49.8%). MR severity was abstracted from clinical echocardiography reports using a 6-level ordinal scale. MR worsening was defined as a [&ge;]1-grade increase from baseline MR at ~30 days or ~1 year. Multivariable logistic models identified predictors of MR worsening. Kaplan-Meier and Cox models evaluated associations of MR trajectory and LFAS subtype with all-cause death, heart failure hospitalization (HFH), and their composite. Results: Among 614 LFAS patients, 443 had 30-day and 290 had 1-year echocardiographic follow up. At 30 days, MR trajectory differed significantly across LFAS phenotypes, with the highest rate of worsening in cLFLG and the lowest in LFHG. At 1 year, unadjusted MR trajectory distributions did not differ significantly across phenotypes. In adjusted logistic models, cLFLG remained independently associated with MR worsening at both timepoints. MR worsening was associated with worse unadjusted outcomes at 30 days but was not independently associated with the composite endpoint after multivariable adjustment. LFAS phenotype, particularly cLFLG, remained the dominant predictor of adverse clinical outcomes. Conclusions: MR evolution after TAVR is phenotype-specific: cLFLG patients have the highest risk of MR worsening and lowest event-free survival, supporting phenotype-informed post-TAVR surveillance.

Background: Severe aortic stenosis is associated with systemic and splanchnic hemodynamic disturbances that may alter gut microbial metabolism and host inflammatory responses. Objectives: We aimed to determine whether TAVI remodels the gut microbiome-derived metabolome and whether post-procedural SCFA dynamics are associated with the inflammatory cytokine response. Methods: We conducted a prospective paired single-center study of patients undergoing elective TAVI at Bern University Hospital. Stool and blood samples were collected before and three months after the procedure. Gut microbial composition was profiled by full-length 16S rRNA sequencing, circulating short-chain fatty acids (SCFAs) by targeted metabolomics, and inflammatory mediators by multiplex cytokine analysis, and integrated with hemodynamic and clinical data. Results: Forty patients were enrolled. Following TAVI, microbial richness declined without significant restructuring of overall community composition. In contrast, circulating SCFA profiles were significantly remodeled, driven by selective reductions in butyrate and isovalerate. A greater decline in circulating butyrate was inversely associated with IL-18 elevation (rho=0.668, p<0.001, n=36), independent of aortic valve calcification burden, hemodynamic improvement, and cardiovascular medications. Baseline isovalerate was nominally associated with 1-month adjudicated adverse events (AUC 0.77; exploratory). Conclusions: TAVI is associated with selective changes in gut microbiome-derived metabolic output rather than broad alterations in microbial community structure. Declining circulating butyrate identifies a gut-metabolite-immune axis linked to IL-18 dynamics and represents a potential biomarker of inflammatory recovery following valve intervention.

BACKGROUNDInterleukin-27 (IL-27) is a heterodimeric cytokine that serves as a bifunctional rheostat rather than an inherently pro- or anti-inflammatory signaling protein. However, the specific role of IL-27 in regulating systolic overload-induced cardiac inflammation and heart failure (HF) pathogenesis remains unknown. METHODSWe investigated the effects of genetic IL-27 receptor deficiency (IL-27R knockout), pharmacological IL-27 blockade, and recombinant IL-27 administration on transverse aortic constriction (TAC)-induced HF in mice. RESULTSCardiac IL-27 expression was significantly elevated in both murine and human HF tissues. The global genetic ablation of the IL-27 receptor (IL-27R) significantly suppressed TAC-induced cardiac inflammation, fibrosis, hypertrophy, HF progression, and mortality. Corroborating these protective effects, transcriptomic analysis (RNA-seq) revealed that IL-27R deficiency drastically suppressed pathways driving immune responses and antigen presentation, alongside the significant downregulation of networks governing systemic inflammation, pathogen infection, and extracellular matrix remodeling. Furthermore, pharmacological neutralization of IL-27 effectively attenuated TAC-induced left ventricular dysfunction, chamber dilation, myocardial hypertrophy, fibrosis, and leukocyte infiltration. Conversely, the administration of recombinant mouse IL-27 exacerbated the TAC-induced cardiac accumulation of multiple immune cell subsets, resulting in worsened cardiac fibrosis, cardiomyocyte hypertrophy, and overall HF progression. CONCLUSIONSOur findings demonstrate that IL-27 acts as a critical pathogenic driver of cardiac inflammation and HF development by modulating both cardiac immune cells (predominantly T cells) and non-immune cells, highlighting the IL-27 signaling axis as a promising therapeutic target.

RationaleHypertrophic cardiomyopathy (HCM) is a common inherited cardiac disorder characterized by cardiac hypertrophy, fibrosis, arrhythmias, and sudden cardiac death (SCD). Although current therapies primarily target sarcomere dysfunction, the contribution of epigenetic dysregulation to HCM pathogenesis and its therapeutic potential remain poorly understood. ObjectiveTo determine whether pharmacological inhibition of histone lysine demethylases (KDMs) with JIB-04 can prevent or reverse HCM progression and to identify the underlying epigenetic mechanisms. Methods and ResultsWe evaluated the pan-KDM inhibitor JIB-04 in Myh6R403Q/+ mice carrying the murine equivalent of the pathogenic human MYH7 R403Q mutation. JIB-04 prevented disease progression, reduced cardiac hypertrophy and fibrosis, preserved cardiac function, and completely prevented SCD in cyclosporin A- accelerated HCM. JIB-04 also reversed established disease, produced sustained therapeutic benefits after drug withdrawal, and improved cardiac function in aged mice with spontaneous HCM. Bulk RNA sequencing and ATAC-seq demonstrated partial restoration of disease-associated transcriptional programs and chromatin accessibility. Proteomic analyses identified PHF2 (KDM7C) as a candidate target of JIB-04 in both mouse and human HCM hearts. PHF2 knockdown suppressed hypertrophic, inflammatory, and fibrotic gene expression in cardiomyocytes, macrophages, and fibroblasts, respectively. Human HCM hearts exhibited increased expression of multiple JIB-04-sensitive KDMs, including PHF2. In MYH7 R403Q induced pluripotent stem cell- derived cardiomyocytes, JIB-04 normalized disease-associated gene expression, restored connexin-43 membrane localization, and improved mitochondrial respiration. Although prolonged treatment induced reversible hepatomegaly with hepatic lipid accumulation, co-administration of the antioxidant N-acetylcysteine mitigated liver toxicity while preserving the therapeutic efficacy of JIB-04. ConclusionsPharmacological KDM inhibition prevents and reverses HCM through epigenetic remodeling of disease-associated transcriptional and chromatin programs. These findings identify KDM inhibition as a promising therapeutic strategy for HCM, establish PHF2 as a candidate mediator of disease pathogenesis, and support further development of KDM-targeted therapies.

BackgroundHeart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome associated with metabolic stress, hypertension, systemic inflammation, and microvascular dysfunction. Early cell-type-specific events and intercellular communication programs that accompany disease onset and progression remain poorly defined. MethodsWe performed a longitudinal study of HFpEF progression in high-fat diet (HFD)+L-NAME mice at control/baseline (0 weeks, 0w/Ctrl), early (1w), intermediate (4w), and established (8w) stages. Metabolic, hemodynamic, exercise, echocardiographic, and single-cardiomyocyte function were assessed. Cardiac non-cardiomyocytes (non-CMs) were profiled by single-cell RNA sequencing (scRNA-seq), with bulk RNA-seq for tissue-level comparison. Endothelial remodeling was assessed in an L-NAME-independent HFD plus mild transverse aortic constriction model (HFD+mTAC) and a published human HFpEF single-nucleus RNA-seq cohort. An endothelial-macrophage adhesion assay tested whether HFpEF-mimic stress promotes endothelial activation and macrophage adhesion. ResultsIn the HFD+L-NAME model, metabolic dysfunction, hypertension, reduced exercise tolerance, abnormal diastolic filling with preserved ejection fraction, and altered cardiomyocyte calcium handling were detected by 1w and persisted through 8w. Bulk RNA-seq showed progressive remodeling, with limited change between 8w and 12w, guiding scRNA-seq timepoint selection. scRNA-seq of 94,848 cardiac non-CMs identified nine major populations with stage-dependent remodeling. Endothelial cells (ECs) were recovered in high proportion and showed an early, pronounced transcriptional response, with inflammatory, adhesion, interferon-response, migratory, and vascular-remodeling programs emerging by 1w. Related EC activation signatures were observed in HFD+mTAC and human HFpEF data. Functionally, HFpEF-mimic stress increased adhesion and chemokine expression in human ECs and enhanced macrophage adhesion. Fibroblast matrix remodeling occurred at later stages, while macrophages progressively shifted toward inflammatory states. CellChat suggested stage-dependent communication remodeling from early endothelial-immune interactions toward later macrophage-fibroblast crosstalk. ConclusionTime-resolved scRNA-seq reveals coordinated, stage-dependent remodeling of the cardiac microvascular and interstitial microenvironment during HFpEF progression. Early endothelial activation emerges before later fibroblast matrix remodeling and inflammatory macrophage remodeling, identifying candidate cell states and signaling pathways for future mechanistic investigation. Clinical PerspectiveO_ST_ABSWhat Is New?C_ST_ABSO_LIThis study provides a time-resolved single-cell atlas of the cardiac non-cardiomyocyte compartment across baseline, early, intermediate, and established stages of HFpEF progression, rather than a single late-stage snapshot. C_LIO_LIEndothelial cells exhibit early inflammatory, adhesion, interferon-response, and vascular-remodeling programs within the first week of disease, preceding the later predominance of fibroblast matrix remodeling and inflammatory macrophage remodeling. C_LIO_LIThis endothelial activation signature is supported across two mechanistically distinct HFpEF mouse models and aligns with endothelial inflammatory and vascular-remodeling programs in human HFpEF myocardium, supporting its translational relevance. C_LI What Are the Clinical Implications?O_LIEarly endothelial activation may represent a targetable stage of HFpEF pathogenesis that arises before more established structural and fibrotic remodeling. C_LIO_LITherapeutic strategies aimed at limiting endothelial inflammatory activation or endothelial-immune interactions may help attenuate downstream vascular, immune, and stromal remodeling in HFpEF. C_LIO_LIThese findings provide a preclinical foundation for future longitudinal human studies testing whether early endothelial activation can serve as a biomarker, therapeutic target, or disease-staging feature in HFpEF. C_LI

Rationale: Pulmonary hypertension is defined by pulmonary hemodynamics, but diagnostic and prognostic biomarkers remain limited. Nuclear magnetic resonance (NMR) spectroscopy provides detailed insights, particularly in the lipid metabolism. Objectives: To explore circulating NMR-derived metabolites and lipoprotein-related parameters for their association with pulmonary hemodynamics and to analyse their prognostic properties in pulmonary arterial hypertension (PAH). Methods: Retrospective analysis of a PAH cohort with complete diagnostic workup including right heart catheterization and baseline serum samples, from the prospective GRaz Pulmonary Hypertension-Metabolism (GRAPH-M) registry. Measurements: NMR-derived metabolites and lipoprotein-related parameters were analyzed for their association with clinically relevant parameters of PAH. We defined PHIHDL, a score derived from high-density lipoprotein (HDL) related measures based on their strong association with pulmonary hemodynamics, and evaluated its prognostic value. Results: We included 100 patients with PAH treated at the PH clinic of LKH University Hospital, Medical University of Graz, between 2011 and 2021. Age was 61{+/-}15 years, female/male ratio 2.5, BMI 26 {+/-}7 kg/m2, mPAP 41{+/-}16 mmHg, PAWP 8.8{+/-}3.2 mmHg, PVR 8.0{+/-}4.9 WU, and median survival was 8.0 years. During follow-up, 46 patients died. We identified a cluster of 12 HDL-related measures that showed significant inverse association to pulmonary hemodynamics and derived PHIHDL from the reversed scaled average of these particles. PHIHDL was associated with all-cause mortality after adjustment for age and sex (HR 2.96, 95% CI 1.52-5.70), independent of the clinical risk scores COMPERA 2.0 and REVEAL Lite2. Conclusion: PHIHDL, a pulmonary hemodynamics-based metabolomic score, provides independent prognostic information beyond established risk scores in PAH.