Circulation

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.

BackgroundCardiometabolic heart failure with preserved ejection fraction (HFpEF) is associated with systemic and cardiac inflammation and diastolic dysfunction. A-kinase anchoring protein 6{beta} (AKAP6{beta}) is a scaffold protein located at the cardiomyocyte outer nuclear membrane that promotes pathological cardiac remodeling via the recruitment of multiple regulatory proteins including protein kinases. In mice, adeno-associated virus (AAV) mediated expression of a peptide based upon a kinase binding domain (KBD) within AKAP6{beta} inhibited the development of heart failure due to chronic pressure overload. Whether KBD expression can also inhibit the development of cardiometabolic heart failure is unknown, and if so, the mechanism of KBD action in HFpEF has yet to be explored. MethodsThe efficacy of a cardiotropic self-complementary AAV gene therapy that expresses the AKAP6{beta} KBD peptide (AAV9sc.KBD) was tested in a female Ossabaw swine model of cardiometabolic syndrome and HFpEF. Single nucleus and bulk RNA sequencing of swine heart tissue and immunoprecipitation-mass spectrometry, live cell imaging, and biochemical assays using primary rat cardiomyocytes were employed to study KBD mechanism of action. ResultsAAV9sc.KBD inhibited the development of diastolic dysfunction and heart failure in the Ossabaw model, without negatively impacting systolic function. The improvement in cardiac phenotype was associated with decreased T-cell myocardial infiltrates and partial reversal of pathological gene expression. An unbiased interactome study revealed that the KBD peptide binds Ca2+/calmodulin-dependent protein kinase II (CaMKII), identifying CaMKII as a new AKAP6{beta} binding partner. Perinuclear CaMKII activity detected by live cell imaging required AKAP6{beta} expression and was inhibited by KBD expression. In addition, the CaMKII substrate Inhibitor of NF-{kappa}B Kinase {beta} (IKK{beta}) bound AKAP6{beta}. IKK phosphorylation in the Ossabaw model and in myocytes was inhibited by KBD expression, and NF-{kappa}B nuclear translocation in myocytes was dependent upon AKAP6{beta}-CaMKII protein complex formation. AAV9sc.KBD treatment inhibited cardiomyocyte NF-{kappa}B-dependent gene expression in the Ossabaw model. ConclusionsRegulated by perinuclear AKAP6{beta}-CaMKII signalosomes, NF-{kappa}B pro-inflammatory gene expression in cardiomyocytes participates in a positive feedback loop with cardiac inflammation promoting HFpEF. Proof-of-concept is provided in a large animal model that gene therapy-based cardiomyocyte expression of the KBD peptide will prevent cardiac dysfunction in cardiometabolic syndrome. Clinical PerspectiveO_ST_ABSWhat is newC_ST_ABSO_LIThe cardiomyocyte-selective gene therapy AAV9sc.KBD, which targets signalosomes organized by the scaffold protein AKAP6{beta}, is shown to inhibit myocardial T-cell infiltration and improve cardiac structure and function in a large animal model of cardiometabolic HFpEF. C_LIO_LIThe AKAP6{beta} KBD peptide is shown to bind and inhibit the function of CaMKII. C_LIO_LICaMKII and IKK{beta} are shown to participate in perinuclear AKAP6{beta} signalosomes, where they regulate activation of the NF-{kappa}B pro-inflammatory gene regulatory pathway. C_LI Clinical implicationsO_LIProof-of-concept for a novel strategy for the treatment of HFpEF is provided, intracellular expression by a cardiomyocyte-selective gene therapy vector of an inhibitory peptide, which will inhibit compartmentalized intracellular signal transduction. C_LIO_LIIn conjunction with previous studies in small rodents, the new data obtained in Ossabaw swine support clinical translation of the AAV9sc.KBD gene therapy. C_LI

Brugada syndrome (BrS) is an inherited arrhythmia disorder with limited drug therapy, quinidine being the principal agent. Loss-of-function variants in SCN5A reduce the cardiac sodium current (INa), but the arrhythmogenic imbalance also depends on the transient outward potassium current (Ito). Here we generated human induced pluripotent stem cell-derived cardioids with right-ventricular identity from a patient carrying an SCN5A frameshift variant (p.A665Gfs*16) and characterised them by patch-clamp and optical mapping. BrS cardioids showed 60% lower peak INa, more than doubled Ito, 38% slower conduction and 76% longer spontaneous cycle length. We then tested AR-788, a benzylaminothiazole-benzimidazole carboxamide of the ARumenamide class. In wild-type (WT) cardiomyocytes AR-788 inhibited Ito concentration-dependently (12%, 30% and 42% at 5, 10 and 20 uM; extrapolated IC50 25.4 uM), and at 10 uM it returned BrS Ito to the level of untreated WT cells (21.71 vs 21.48 pA/pF, p = 0.9716) without reducing INa. It also reduced the rapid delayed-rectifier current (IKr) tail current by 40%, a liability requiring formal proarrhythmia profiling. These data identify AR-788 as an Ito-suppressing member of the ARumenamide class and provide proof of concept that a small molecule can correct the potassium-current excess in a human BrS model.

BackgroundTakotsubo syndrome (TTS) is an acute stress-induced cardiomyopathy characterized by transient left ventricular dysfunction. Despite its reversible nature, TTS is associated with substantial morbidity and mortality in the acute phase, and no specific treatments are available. The precise molecular mechanisms that connect catecholamine stress to reversible myocardial injury are not fully understood. PP2A, a holoenzyme with serine/threonine phosphatase activity, plays a vital role in normal cardiac development, and its dysregulation has been associated with heart disease. Its role in TTS and its potential as a therapeutic target remain completely unknown. MethodsAnalysis of public multi-omics datasets from stress cardiomyopathy (SCM) and experimental models of TTS, along with treatment of cardiomyocytes with human TTS plasma, was used to investigate a potential role for protein phosphatase 2A (PP2A) in stress-induced myocardial injury. To clarify the functional impact of manipulating PP2A activity in TTS, we used a series of disease relevant cell based and in vivo models, leveraging both genetic and pharmacological approaches to modulate PP2A activity in cardiomyocytes and in mice. To gain mechanistic insights into how PP2A influences TTS pathology and downstream signaling pathways, RNA sequencing, stress-responsive iron handling, mitochondrial function, and cardiac phenotypes were thoroughly evaluated in both in vivo and in vitro studies. ResultsPP2A activity was markedly reduced in cardiac tissues from mice with isoprenaline-induced TTS, as well as in isoprenaline-treated cardiomyocytes. Genetic or pharmacological inhibition of PP2A worsened catecholamine-induced cardiac dysfunction and myocardial injury. Most notably, pharmacological activation of PP2A using an orally bioavailable small-molecule activator strongly mitigated myocardial damage and enhanced cardiac function in TTS models. Mechanistically, PP2A inactivation promoted JNK-MAPK signaling and dysregulated stress-responsive iron-handling pathways, leading to ferritinophagy-mediated ferroptosis and mitochondrial dysfunction. Pharmacological JNK inhibition effectively rescued myocardial injury caused by PP2A deficiency in two TTS animal models and in cardiomyocytes. ConclusionsPP2A inactivation is a key molecular event linking catecholamine stress to myocardial injury in TTS. Restoring PP2A activity or inhibiting downstream JNK attenuates ferritinophagy-dependent stress responses and mitochondrial dysfunction, providing a unifying mechanistic framework and highlighting the PP2A-JNK axis as a potential target for short-term intervention during the acute phase of TTS. CLINICAL PERSPECTIVEO_ST_ABSWhat Is New?C_ST_ABS* Protein phosphatase 2A (PP2A) activity is acutely suppressed during the early phase of Takotsubo syndrome (TTS), with preferential involvement of the apical myocardium, closely mirroring the diseases characteristic clinical phenotype. * Downstream of PP2A inactivation, catecholamine stress triggers JNK-MAPK signaling activation and dysregulated stress-responsive iron handling, including ferritinophagy-mediated ferroptosis and mitochondrial dysfunction in cardiomyocytes. * Pharmacological restoration of PP2A activity or downstream inhibition of JNK mitigates acute myocardial injury and preserves cardiac function, thereby establishing the PP2A-JNK axis as a central stress-responsive pathway in TTS. What Are the Clinical Implications?* Identification of PP2A inactivation as a key molecular event highlights a novel opportunity for targeted intervention during the acute phase. * Studies in preclinical animal TTS models provide the first evidence that illuminates the therapeutic potential of a small-molecule PP2A activator as a strategy for acute TTS and may serve as a broad cardioprotective strategy in settings where cardiac dysfunction is implicated. * Targeting downstream JNK signaling, which is activated by PP2A inactivation, emerges as an additional mechanism-based strategy for attenuating acute myocardial injury in TTS.

Despite the widespread use of L-type calcium channel blockers (CCBs), recent observational and murine functional work has suggested a potential adverse effect of this medication class on the aorta. Here, we apply a Mendelian randomization (MR) framework to assess the potential causal role of CACNA1C - the principal target of L-type CCBs in the human aorta - on thoracic aortic aneurysm and dissection (TAA/D). Genetic instrumental variables were derived from aortic expression quantitative trait locus data, and combined with large-scale genome-wide association data of TAA/D and ascending aortic diameter. Mirroring the on-target vascular effects of L-type CCBs, higher genetically predicted CACNA1C expression was linked to higher blood pressure, and to higher risks of hypertension and coronary artery disease. In contrast, higher predicted aortic expression of CACNA1C was linked to lower risk of TAA/D ({beta}=-0.18, P=0.005) and to a smaller ascending aortic diameter in the general population ({beta}=-0.08, P=0.005). While we caution against overinterpretation of our MR results in isolation, the convergence with observational and functional data calls for dedicated clinical trials to assess the safety of CCBs in the context of aortic disease.

Importance Evolocumab reduces major adverse cardiovascular events (MACE) in patients with clinically evident atherosclerotic cardiovascular disease (ASCVD) and in patients at high cardiovascular (CV) risk but without a prior myocardial infarction (MI) or stroke. While evolocumab is shown to be cost-effective in clinically evident ASCVD, emerging CV outcomes evidence and newer guideline recommendations warrant assessment in patients at high CV risk without a prior MI or stroke. Objective To evaluate the cost-effectiveness of evolocumab added to standard therapy compared with standard therapy alone in patients at high CV risk without a prior MI or stroke, as represented by the VESALIUS-CV trial. Design, Setting, and Participants A previously published Markov cohort state-transition model was adapted to simulate VESALIUS-CV patients over a lifetime horizon. Health states included high-risk without a prior MI or ischemic stroke (IS), non-fatal MI, non-fatal IS, post-MI, post-IS, CV death, and non-CV death. Revascularization (RV) was modeled as a procedure with associated costs. The base case considered a US payer perspective and CV risk reduction inputs from evolocumab CV outcomes trials, including VESALIUS-CV, FOURIER, and FOURIER-OLE. Three scenario analyses were evaluated. Scenario 1 retained the US payer perspective and applied CV risk reduction estimates based on the Cholesterol Treatment Trialists' (CTT) Collaboration 2010 meta-analysis. Scenarios 2 and 3 adopted a US societal perspective, using evolocumab CV outcomes trial-based and 2010 CTT Collaboration-based risk reduction estimates, respectively. Main Outcomes and Measures The model outcomes included MACE (defined as MI, IS, or CV death), RV procedures, total costs, life-years (LYs), quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (ICER). Results In the base case, at the current direct-to-patient price of $3,107 per year, evolocumab added to standard therapy was associated with lifetime reductions of 0.24 MACE and 0.17 RV procedures per person, incremental costs of $24,430, incremental QALYs of 0.34, and an ICER of $71,162 per QALY gained. Evolocumab remained cost-effective across all evaluated scenarios, with ICERs of $42,094, $51,160, and $20,152 per QALY in Scenarios 1, 2, and 3, respectively. Conclusions and Relevance In patients at high CV risk without a prior MI or stroke, evolocumab added to standard therapy was projected to improve CV outcomes and quality-adjusted survival. At the current direct-to-patient price of $3,107 per year, evolocumab was cost-effective in the base-case analysis, with an ICER of $71,162 per QALY gained, and remained cost-effective across scenario analyses, with ICERs ranging from $20,152 to $51,160 per QALY. These estimates were substantially below the $120,000 per QALY threshold defined in the 2025 American Heart Association/American College of Cardiology cost/value methodology statement.

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: The epicardium is reactivated after myocardial infarction (MI); however, the gene expression profiles of post-MI adult epicardial subpopulations remain incompletely defined. Methods: Single-cell RNA sequencing was performed on lineage-traced Wt1+ epicardial cells from Wt1CreERT2/+; R26tdT/+; PdgfranGFP/+ adult mice after sham surgery or at 7 and 14 days after permanent artery ligation to induce MI. Immunostaining was performed on Wt1-lineage-traced cardiac tissue to validate spatial expression after ischemic injury. Results: Unbiased clustering identified nine transcriptionally distinct epicardial populations, encompassing mesothelial, fibroblast/mesenchymal, transitional, and proliferative phenotypes. Fibroblast-like epicardial cells (Wt1+/Pdgfra+) showed time-dependent expression profiles associated with upregulation of epithelial-to-mesenchymal transition (EMT) and extracellular matrix (ECM) gene programs. At 7 days post-MI, there was notable enrichment of genes related to chemokines and Wnt components. By 14 days post-MI, the expression profile shifted toward immune regulation. In contrast, a Wt1high/Msln+ population showed minimal upregulation of EMT gene programs but enhanced paracrine signaling related to wound healing and semaphorins, suggesting reactivation of reparative and angiogenic functions akin to those of the epicardium during embryonic development. Immunostaining and in situ hybridization fluorescence analyses validated laminar epicardial cell placement after MI, comprising a surface Msln+ sheet, an overlapping Wt1-lineage band, and a subadjacent PDGFR+ and Periostin+ compartment that expands 7-14 days after MI and regresses by day 28 post-ischemia. Conclusions: Our data define epicardial gene programs in which a signaling epithelial cell surface overlays an effector mesenchymal cell stroma to coordinate angiogenesis, leukocyte recruitment, and ECM remodeling. This study presents the first integrated single-cell atlas of epicardial-derived cells across multiple post-ischemic timepoints, offering new insights into their reparative potential and dynamic signaling diversity in the injured adult heart.

Background: Previous studies of genotype-phenotype correlations in hypertrophic cardiomyopathy (HCM) have presented inconsistent conclusions, potentially reflecting small studies and non-uniform phenotyping. Objectives: We aimed to identify genotype-phenotype correlations in sarcomeric variant-positive HCM cardiac magnetic resonance (CMR) imaging and adverse outcome data in the National Heart, Lung, and Blood Institute (NHLBI) HCM Registry. Methods: Of 2750 overall patients, 915 sarcomeric variant-positive ones were subgrouped by genotype. CMR measures of left ventricular (LV) hypertrophy, fibrosis and function, and adverse events, were compared. Findings were meta-analyzed with prior studies from systematic review. Results: Patients with pathogenic variants in thick-filament genes had greater hypertrophy than those in thin-filament genes - maximal LV wall thickness (maxLVWT) (21.7 {+/-} 5.0 vs. 20.0 {+/-} 4.4mm, P<0.01) and indexed LV mass (81.9 {+/-} 26.0 vs. 71.7 {+/-} 13.3g/m2, P<0.001). Of the former, MYBPC3 carriers had greater maxLVWT than MYH7 carriers (22.2 {+/-} 5.2 vs. 20.9 {+/-} 4.5mm, P<0.01) but lower LV ejection fraction (63.1 {+/-} 8.4 vs. 65.3 {+/-} 8.4%, P<0.001). Findings remained significant after covariate adjustment and meta-analysis. 23 (~1%) patients had >1 disease-linked variants with only 3 (~0.11%) carrying >1 pathogenic variants. MYBPC3 carriers had lower risk of a multiple event composite than MYH7 carriers. Conclusions: In the largest CMR-based study to date, we identified significant phenotypic differences that characterize disease-gene subgroups and resolved prior discrepancies through systematic review and meta-analysis. However, carriage of >1 sarcomeric variants did not contribute much to variation in phenotypic severity in the general HCM population due to its rarity.

Background: In obstructive hypertrophic cardiomyopathy, surgical myectomy is highly effective but carries a recognized risk of postoperative conduction disturbances. Percutaneous intramyocardial septal radiofrequency ablation (Liwen procedure) is a less invasive alternative, but head-to-head comparisons of longitudinal hemodynamic trajectories and conduction system safety remain scarce, limiting evidence-based treatment selection. Methods: This single-center retrospective cohort included 211 patients treated 2018?2023 (124 Liwen, 87 modified Morrow myectomy). The primary longitudinal analysis included 133 patients with 1-year follow-up and serial data (75 Liwen, 58 modified Morrow myectomy). Repeated outcomes were analyzed using linear mixed-effects models and generalized estimating equations, adjusted for baseline covariates. Results: Both procedures reduced LVOT gradient, but trajectories differed (interaction P=0.002). At 1 year, the covariate-adjusted mean LVOT gradient remained higher after Liwen than after myectomy (16.1 vs 1.3 mmHg, P<0.001). However, the adjusted 1-year predicted probability of new conduction abnormalities was markedly lower after Liwen (5% vs 62%, P<0.001), with no permanent pacemaker implantations in the Liwen group. Most patients achieved gradient <30 mmHg in both groups (82% vs 96%; nominal P=0.308). Liwen had shorter procedure duration (80 vs 185 min) and hospital stay (11 vs 16 days). Serious adverse event rates were similar (8.1% vs 9.2%) but profiles differed. Conclusions: Modified Morrow myectomy achieved more complete LVOT gradient reduction at 1 year, whereas Liwen ablation had fewer conduction abnormalities, shorter procedure duration, and shorter hospital stay. These findings highlight a clinically relevant trade-off between more complete hemodynamic relief and lower conduction-system injury and require prospective confirmation.

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 Therapies to prevent ventricular arrhythmias after completed myocardial infarction (MI) remain limited. Although TRPV1 afferent ablation at acute MI improves cardiac remodeling, the effect of delayed subacute targeting remains unknown. Objective We investigated whether ablating cardiac TRPV1 afferents during the subacute post-MI window mitigates structural, electrophysiological, and neuro-cardiac axis remodeling to suppress ventricular arrhythmias. Methods Yorkshire pigs underwent sham surgery or anterior MI creation. Two weeks post-MI, animals were randomized to percutaneous epicardial resiniferatoxin (RTX, for cardiac-selective TRPV1 afferent depletion) or vehicle administration. Four weeks later, terminal studies assessed the effects of RTX on cardiac structure and function, ventricular arrhythmogenesis, and neuro-cardiac axis remodeling using in vivo electrophysiologic mapping, real-time neurotransmitter sensing, immunohistochemistry, and transcriptomic profiling. Results Cardiac TRPV1 afferent depletion was confirmed by blunted responses to TRPV1 agonists. RTX-treated animals exhibited improved left ventricular function, reduced end-diastolic diameter, and suppressed ventricular tachycardia/fibrillation (VT/VF) inducibility. Endocardial electroanatomic mapping revealed improved VT/VF electrophysiologic correlates in RTX-treated animals, including fewer deceleration zones and late potentials. Epicardial multielectrode mapping demonstrated reduced electrophysiologic heterogeneity in the scar border zone. Real-time release of adrenergic neurotransmitters (noradrenaline and neuropeptide Y) was normalized during sympathoexcitation in RTX-treated animals. Histologically, RTX treatment attenuated scar border zone myocardial fibrosis and sympathetic nerve sprouting, while suppressing T cell infiltration in cardiac sensory ganglia. Bulk RNA-sequencing of stellate ganglia revealed downregulation of adrenergic genes. Conclusion Cardiac TRPV1 afferent ablation post-completed MI alters disease trajectory by mitigating structural, functional, and neuro-cardiac axis remodeling. Targeting cardiac TRPV1 afferents represents a promising subacute post-MI therapeutic strategy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a pan-ethnic disease, at least as common in Black as in White Americans, yet Black patients reach specialist care later, undergo septal reduction less often, and die sooner. Whether the defining trials enrolled representatively is unknown. We sought to measure Black participation in the landmark HCM trials against three expectations of increasing stringency, and to test whether trial site geography or quantitative eligibility thresholds account for the shortfall. METHODS: Of 197 registered interventional HCM trials, 32 met prespecified landmark tiers; demographics were extracted for 16 and 13 reported race. The Black share of Black plus White participants was pooled by random-effects meta-analysis and compared with the US adult population, with each trial?s own site counties, and with a disease-referenced echocardiographic expectation. Site geography and eligibility thresholds were tested using site addresses, census data, and NHANES. RESULTS: Across 13 trials, 70 of 1,780 Black or White participants were Black. The pooled Black share was 3.98% (95% CI 2.68-5.86), against a population expectation of 16.5%, giving a participation-to-prevalence ratio (PPR) of 0.24 (95% CI 0.16-0.36), the lowest of any racial and/or ethnic minority group. The clinical trial site network reached 63.7% of Black and 47.5% of White US adults, with geospatial analysis predicting 26.4% Black enrollment; however, every trial fell below this expectation. Quantitative eligibility thresholds closed only 2.0% of the enrollment gap. CONCLUSIONS: Black participation was about one quarter of the population expectation. Neither site geography nor eligibility thresholds explain it.

Aortic stenosis (AS) is a heterogeneous disease of aging characterized by valvular calcification and distinct structural, electrical, and hemodynamic remodeling that are incompletely captured by any single diagnostic measure. Here we show that three AI-derived digital biomarkers resolve AS-related remodeling into complementary structural (cine-CMR Digital AS Severity Index, DASSi), electrical (AI-ECG), and hemodynamic (phase-contrast CMR peak aortic velocity) axes. Among 68,714 UK Biobank participants, all three biomarkers were independently associated with prevalent AS and prospectively predicted aortic valve replacement. Genetic and transcriptomic analyses of the digital phenotypes revealed partially distinct, heritable architectures: peak aortic velocity aligned closely with clinical AS genetics, whereas DASSi and AI-ECG defined a shared myocardial-remodeling axis largely independent of clinical AS susceptibility. These findings support AS as a multidimensional remodeling syndrome and establish a novel digital phenotyping framework for dissecting complex cardiovascular disease into complementary, biologically informative axes.

BackgroundNeutrophil extracellular traps (NETs) contribute to immunothrombosis and arterial thrombosis. Mechanisms underlying myocardial infarction after SARS-CoV-2 vaccination remain poorly understood. ObjectivesTo investigate histopathologic and immunothrombotic features of coronary thrombi in patients with ST-elevation myocardial infarction (STEMI) after SARS-CoV-2 vaccination. MethodsWe performed a retrospective matched cohort study including patients with STEMI undergoing primary percutaneous coronary intervention between January 2021 and March 2023. Coronary thrombi obtained by aspiration were analyzed by histopathology, immunohistochemistry, and confocal microscopy for NET detection. Vaccinated and unvaccinated patients were matched by age and sex. Associations between vaccination status and thrombus characteristics were assessed after adjustment for SARS-CoV-2 serologic status. ResultsAmong 44 matched patients (23 vaccinated and 21 unvaccinated), NETs were identified in 14 vaccinated patients (61%) and 5 unvaccinated patients (24%; P = .01). Vaccination was associated with increased odds of NET-positive thrombi after adjustment for SARS-CoV-2 serology (odds ratio, 5.1; 95% CI, 1.36-19.45; P = .02). No associations were observed between vaccination and polymorphonuclear cell density, fibrin deposits, plaque fragments, or anti-platelet factor 4 staining. Among patients vaccinated within 100 days before STEMI, NET-positive thrombi were associated with shorter intervals between vaccination and myocardial infarction (median [IQR], 25 [11-64] vs 57 [40-84] days; P = .02). ConclusionsSARS-CoV-2 vaccination was associated with increased NET presence in coronary thrombi from patients with STEMI, suggesting a potential NET-mediated immunothrombotic mechanism independent of classical vaccine-induced immune thrombotic thrombocytopenia.

Background. Cuproptosis, a copper-dependent form of regulated cell death, has been repeatedly reported to be transcriptionally activated in atherosclerotic plaque, and cuproptosis- and copper-transport genes have been nominated as candidate biomarkers and therapeutic targets on the basis of descriptive expression studies. Whether genetically determined expression of these genes is causally related to atherosclerotic cardiovascular disease has not been tested. Methods. We first confirmed, across two independent carotid plaque transcriptomic cohorts (GSE43292 and GSE28829), that a panel of copper-metabolism and cuproptosis genes is concordantly dysregulated in plaque and that the copper importers track the degree of inflammatory-cell infiltration. We then performed two-sample cis-Mendelian randomization (MR) and Bayesian colocalization to test the causal effect of the genetically predicted expression of 11 cuproptosis/copper genes on coronary artery disease (CAD). Instruments were cis-eQTLs from whole-blood (eQTLGen, n = 31,684) and tibial artery (GTEx v8, n = 584); the outcome was CAD (CARDIoGRAMplusC4D/Aragam 2022; 181,522 cases, 1,165,690 participants, European ancestry). Large-artery atherosclerotic stroke (GIGASTROKE) was examined as a secondary outcome. LPL served as a positive control. The positive control was intended to validate the direction and harmonization of the MR pipeline, not to demonstrate that single-causal-variant colocalization must succeed at a known multi-signal locus such as LPL. Results. In plaque, copper-import genes (SLC31A2, SLC31A1) were upregulated and correlated strongly with myeloid/inflammatory infiltration (SLC31A2 vs. M1-macrophage r = +0.87), whereas the exporter ATP7B correlated inversely (r = -0.73). The positive control LPL showed the expected robust protective effect on CAD (IVW OR 0.90 per SD higher expression, 95% CI 0.87-0.93, P = 4.1 x 10-12), validating the pipeline. None of the 11 cuproptosis/copper genes showed colocalization-supported causal evidence for CAD. Two genes reached nominal MR significance in single-instrument analyses (MTF1 OR 1.16, P = 2.7 x 10-3, DLAT OR 1.41, P = 2.2 x 10-3,) but were not supported by colocalization (MTF1 PP.H4 = 4 x 10-6 with PP.H3 = 0.9998; DLAT PP.H4 = 0.29), indicating linkage-disequilibrium confounding rather than causality. For well-instrumented genes (e.g. ATP7B, SLC31A2, FDX1), estimates were null and precise enough to exclude odds ratios larger than {approx}1.05 per SD. Conclusions. Common cis-regulatory variation determining the baseline expression of cuproptosis/copper-transport genes in available eQTL tissues did not support a detectable causal effect on CAD risk. This does not exclude locally acquired plaque cuproptosis; rather, the reported upregulation of these genes in plaque is most consistent with a consequence or marker of established disease rather than a germline-encoded causal driver, and cautions against target nomination based on descriptive transcriptomics alone. Keywords: cuproptosis; atherosclerosis; coronary artery disease; Mendelian randomization; colocalization

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.

Genetic testing for cardiomyopathy and arrhythmia (CM/ARRH) provides diagnostic information and informs screening for at-risk relatives. Clinical guidelines recommend genetic testing for these conditions; however, data on how genetic test results influence clinical management recommendations are limited. Here, we determined the frequency of cardiologist-recommended management changes for patients following CM/ARRH genetic testing. This was a retrospective cross-sectional study of patients referred for multigene panel testing between April 2016 and April 2024. Genetically-experienced cardiologists at multicenter academic clinical practices were recruited for participation to complete surveys indicating clinical decision making on patients who had genetic testing. Cases for review were randomly selected to have both positive and non-positive results. Among 249 patients (138 positive, 111 non-positive), 136 (54.6%) received clinical management recommendations for their own or their at-risk relatives? care. Of these, 75 (55.1%) received recommendations for the patient?s own care, most frequently additional diagnostic tests/procedures (n=33). Compared to non-positive results, patients with positive results were more likely to receive recommendations for their own management (66/138, 47.8% vs 9/111, 8.1%; P<0.00001). Patients with positive results in arrhythmogenic cardiomyopathy genes had 263% higher odds of recommended management changes compared to those with TTN (OR=3.63, CI:1.40-9.84, P=0.009). The results from CM/ARRH genetic testing on affected patients influenced cardiologists? medical decision making and management recommendations. Additional research is needed to evaluate how genetic testing for CM/ARRH impact health outcomes.

Background: Calcific aortic valve disease (CAVD) lacks disease-modifying therapy. LDL-cholesterol lowering does not attenuate valvular calcification, suggesting cholesterol-independent drivers. Thus, we tested whether ceramide accumulation drives CAVD and whether inhibiting sphingolipid de novo synthesis is therapeutic. Methods: We integrated lipidomics and proteomics of calcified and non-calcified human aortic valves with matched plasma. Mechanistic effects of ceramides were tested in primary human valvular interstitial cells (VICs). Therapeutic efficacy of serine palmitoyltransferase (SPT) inhibition with Myriocin was evaluated in ApoE-/- mice with PCSK9DY-AAV-driven hyperlipidemia on Western diet using preventive treatment and therapeutic initiation after echocardiographically verified gradient elevation. Myriocin was additionally tested in a normolipidemic wild-type aortic valve wire-injury model. Hemodynamics, valve structure, lipid composition, and cell-state transitions were assessed by echocardiography, histology, lipidomics, and single-cell RNA sequencing. Results: Calcified human valves showed enrichment of long-chain ceramides linked to NF-{kappa}B, endothelial-to-mesenchymal transition (EndMT), and ER-stress/unfolded protein response (UPR) programs, whereas matched plasma sphingolipids were not elevated. In hVICs, long-chain C18 ceramide induced GRP78/BiP, CHOP, and ATF4, activated NF-{kappa}B, and promoted dose-dependent calcification. In vivo, SPT inhibition with Myriocin lowered valvular ceramides, reduced leaflet inflammation and mineralization, and improved cusp separation and transvalvular hemodynamics without lowering plasma LDL-cholesterol. In a therapeutic protocol initiated after gradient elevation, Myriocin halted further hemodynamic progression, providing the first evidence that de novo sphingolipid synthesis can be targeted after established CAVD onset in vivo. Myriocin also attenuated injury-induced stenosis in normolipidemic mice. Single-cell RNA sequencing showed reduced NF-{kappa}B/EndMT and ER-stress signatures and shifted VIC states away from osteogenic phenotypes. Conclusions: Human valve lipidomics and human VIC experiments identify ceramide-driven lipotoxicity as a driver of an ER-stress-NF-{kappa}B-EndMT axis in CAVD. In vivo, de novo sphingolipid synthesis is an actionable, LDL-independent target capable of modifying established hemodynamic disease progression, supporting SPT inhibition as a tractable strategy for medical CAVD therapy.

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.