European Heart Journal

Background/PurposeDesmoplakin (DSP) mutations are linked to familial cardiomyopathies with a very high arrhythmogenic propensity. While autosomal recessive inheritance forms manifest in the cardio-cutaneous Carvajal syndrome, the dominant-inheritance variants associate to DSP-cardiomyopathy (DSP-CM). This latter is a subtype of Arrhythmogenic Cardiomyopathy characterized by frequent myocarditis-like episodes, dominant left ventricular (LV) remodeling, recurrent premature ventricular contractions and life-threatening arrhythmias, frequently preceding LV dysfunction and dilation. Notably, DSP-CM evades the diagnostic identifiers of Arrhythmogenic Cardiomyopathy, further complicating risk-stratification and prediction. At the time being, the pathogenetic mechanisms underlying DSP-related cardiomyopathies are largely obscure and their elucidation is urgently required. MethodsTo this end, we employed CRISPR-Cas9 to generate a novel knock-in mouse model harboring a point mutation at the murine ortholog of human Serine-299, a mutation site previously identified in a family affected by left dominant-Arrhythmogenic Cardiomyopathy. In both heterozygotes and homozygotes, cardiac function was assessed by echocardiography and telemetry-ECG, at different ages. Results were correlated with heart structure, which was assessed by ultrastructural, histopathological and molecular/biochemical assays. The effects of moderate exercise on disease manifestations were tested. ResultsThe homo- and hetero-zygous expression of mutant DspS311A allele replicated the human cardiac phenotypes of Carvajal syndrome and DSP-CM, respectively. Indeed, DspS311A/S311A mice featured precocious dilated cardiomyopathy with biventricular fibrotic remodeling, aneurisms, systolic dysfunction, increased arrhythmic vulnerability, sudden death and, remarkably, cutaneous defects. Differently, DspWT/S311A mice did not show evident cutaneous alterations, and myocardial remodeling and contractile dysfunction developed later and were associated to increased cell death, inflammatory response and patchy fibrosis predominantly in the LV. Notably, as observed in certain patient subgroups, DspWT/S311A mice had electrophysiological alterations (i.e. QRS prolongation, distal conduction defects and sustained ventricular arrhythmias) prior to developing contractile dysfunction. Furthermore, in both genotypes, exercise accelerated myocardial remodeling and increased the incidence of arrhythmic mortality. ConclusionsOur novel DspS311A mice recapitulate the clinical and pathological features of the respective dominant (i.e. DSP-CM) and recessive (i.e. Carvajal syndrome) forms of DSP-related cardiomyopathies. Thus, DspS311A mice are a novel experimental model of human diseases, suited to test therapeutic interventions aimed at reducing the burden of stress-dependent SD.

Restrictive cardiomyopathy (RCM) is an uncommon pediatric condition characterised by diastolic dysfunction caused by myocardial stiffness, with preserved systolic function in the early stage. Its pathogenesis is linked to genetic mutations, metabolic defects, or fibrosis, but this process remains incompletely understood. Bioinformatics analysis indicated a crucial role of tropomyosin 2 (TPM2) in pediatric RCM. Using single-nucleus RNA sequencing (snRNA-seq) and proteomics, we identified molecular alterations in RCM hearts compared with controls, with a notable finding that TPM2 expression was markedly reduced in RCM patients. Functional assays showed that TPM2 knockdown in H9C2 cells promoted cell cycle progression (from G0/G1 to S phase), increased apoptosis, and enhanced cell migration. Subsequent western blot analysis confirmed alterations in cyclin-D1 and epithelial-mesenchymal transition (EMT) - related proteins following TPM2 silencing. These findings suggest that TPM2 may act as a cardioprotective factor and biomarker for pediatric RCM, thereby providing new therapeutic targets for this severe condition.

ObjectivesTo identify echocardiographic signatures featuring left ventricular longitudinal strain (LS) associated with genetic risk for cardiac amyloidosis (CA) due to the TTR Val142Ile (V142I) variant in African American (AA) and Hispanic/Latinx (H/L) individuals. BackgroundHereditary transthyretin amyloidosis (hATTR) can cause CA in [~]60-70% of older V142I carriers, but amyloid deposition progresses over many years. Disease-modifying therapy for CA is now available and early initiation is a priority for improving outcomes. Genomic screening programs and familial cascade genetic testing uncover pre-symptomatic V142I carriers, yet no guidelines exist for early CA detection. MethodsExome sequencing data linked to electronic health records (EHRs) of BioMe biobank participants were queried for AA or H/L TTR- and TTR+ (V142I) subjects without hATTR diagnoses and with prior echocardiograms suitable for retrospective LS analysis. Systemic "red flag" features of ATTR were extracted from EHRs of TTR+ subjects. Speckle tracking echocardiography was retrospectively applied to determine global (GLS) and segmental LS. Relative apical sparing (RAS) was calculated. Results57 TTR+ and 46 TTR-age- and ancestry-matched subjects were included. GLS declined with age in females but not males, and was abnormal (<16%) in 18 (31.6%) TTR+ and 7 (15.2%) TTR-subjects (p = 0.066). Apical sparing was observed in 13 (22.8%) TTR+ and 11 (23.9%) TTR-subjects (p = 1.0). After adjusting for relevant demographic and echocardiographic covariates, neither GLS nor RAS was associated with TTR+ V142I status. Red flag features were not associated with GLS or RAS in TTR+ subjects. ConclusionsNeither GLS nor RAS were significantly different between TTR+ and TTR-subjects. Since >50% of TTR+ subjects were [&ge;] 60 years old, penetrance of CA by echocardiography among unselected V142I carriers may be lower than previously estimated. These findings indicate that surveillance for CA in individuals at increased genetic risk due to V142I should not rely solely on echocardiography, even with LS.

BACKGROUNDIsolated posterior leaflet mitral valve prolapse (PostMVP), a common form of MVP, often referred as fibroelastic deficiency, is considered a degenerative disease. PostMVP patients are usually asymptomatic and often undiagnosed until chordal rupture. The present study aims to characterize familial PostMVP phenotype and familial recurrence, its genetic background, and the pathophysiological processes involved. METHODSWe prospectively enrolled 284 unrelated MVP probands, of whom 178 (63%) had bi-leaflet MVP and 106 had PostMVP (37%). Familial screening within PostMVP patients allowed the identification of 20 families with inherited forms of PostMVP for whom whole genome sequencing was carried out in probands. Functional in vivo and in vitro investigations were performed in zebrafishand in Hek293T cells. RESULTSIn the 20 families with inherited form of PostMVP, 38.8% of relatives had a MVP/prodromal form, mainly of the posterior leaflet, with transmission consistent with an autosomal dominant mode of inheritance. Compared with control relatives, PostMVP family patients have clear posterior leaflet dystrophy on echocardiography. Patients with PostMVP present a burden of rare genetic variants in ARHGAP24. ARHGAP24 encodes the filamin A binding RhoGTPase-activating protein FilGAP and its silencing in zebrafish leads to atrioventricular regurgitation. In vitro functional studies showed that variants of FilGAP, found in PostMVP families, are loss-of-function variants impairing cellular adhesion and mechano-transduction capacities. CONCLUSIONSPostMVP should not only be considered an isolated degenerative pathology but as a specific heritable phenotypic trait with genetic and functional pathophysiological origins. The identification of loss-of-function variants in ARHGAP24 further reinforces the pivotal role of mechano-transduction pathways in the pathogenesis of MVP. CLINICAL PERSPECTIVEO_LIIsolated posterior mitral valve prolapse (PostMVP), often called fibro-elastic deficiency MVP, is at least in some patients, a specific inherited phenotypic trait C_LIO_LIPostMVP has both genetic and functional pathophysiological origins C_LIO_LIGenetic variants in the ARHGAP24 gene, which encodes for the FilGAP protein, cause progressive Post MVP in familial cases, and impair cell adhesion and mechano-transduction capacities C_LI

BackgroundGroup 2 pulmonary hypertension (PH) is associated with poor clinical outcomes. Comprehensive epidemiological data on the incidence of Group 2 PH following heart failure (HF) with preserved versus reduced ejection fraction (HFpEF vs. HFrEF) are limited. ObjectivesTo investigate the differential associations of HFpEF vs. HFrEF with incident Group 2 PH. Methods17,212 newly diagnosed HF patients were examined from University of Pittsburgh Medical Center between 10/01/2015 and 03/31/2021. The cumulative incidence of PH was estimated using the Nelson-Aalen method, and associations with clinical risk factors were assessed using Cox proportional hazards models. Men and women were analyzed separately, given established sex differences in HF subtypes. ResultsMean age was 71.7{+/-}13.0 years, 46.3% were women, and 1,636 incident cases of PH were identified up to 4.5-years of follow-up. The cumulative incidence of PH was initially higher in HFrEF but was surpassed by HFpEF after 2 years. The cumulative incidence (95% CI) was 33.51% (32.36%-34.65%) in HFpEF and 30.87% (29.04%-32.65%) in HFrEF. The incidence was higher in women 36.25% (34.84%-37.62%) than in men 29.69% (28.33%-31.02%). HFpEF in women was associated with a 23% higher risk of incident PH vs. HFrEF (HR: 1.23; 95% CI: 1.01-1.50). This differential risk by HF subtype was not seen in men. ConclusionThis study highlights the significant burden of the development of PH in HF with HFpEF showing higher risk, especially in women. These findings suggest that HF subtype and sex may influence PH development through distinct pathways. Condensed abstractGroup 2 pulmonary hypertension (PH) worsens heart failure (HF) outcomes, but its incidence by HF subtype is unclear. In 17,212 UPMC HF patients, PH was initially more common in HFrEF but surpassed by HFpEF after two years. Women had higher PH incidence, with HFpEF increasing PH risk by 23% in women but not in men. These findings highlight the need for PH screening in all HF patients, especially those with HFpEF and women. Integrating PH risk stratification into HF care may support earlier intervention, guide treatment decisions, and improve long-term outcomes in this growing, high-risk population.

BackgroundMitral annular disjunction (MAD), posterior displacement of the mitral valve leaflet hinge point, predisposes to arrhythmias or sudden cardiac death. We evaluated the burden of MAD, mitral valve prolapse (MVP), and mitral regurgitation (MR) by heritable thoracic aortic disease (HTAD) gene in a cross-sectional analysis of 2014-2023 data in the Montalcino Aortic Consortium (MAC) registry. MethodsMAD was determined by direct measurement of echocardiographic images. MR and MVP were defined according to current clinical guidelines. Associations were evaluated using chi-squared or Fisher exact tests. ResultsMR and MVP were enriched in MAC participants (672) with pathogenic variants (PV) in TGF-{beta} pathway genes. The combination of MR and MVP was associated with mitral surgery and arrhythmias. In the subgroup with available images, MAD was enriched in SMAD3 PV compared to other TGF-{beta} PV (PR 1.8 [1.1-2.8], P< 0.02). Severe disjunction (>10 mm) was only observed in the TGF-{beta} subgroup and was further enriched in participants with SMAD3 PV (PR 3.1 [1.1-8.6]). MVP (PR 5.2 [3.0-9.0]) and MR (PR 2.7 [1.8-3.9) were increased in participants with MAD, but MAD was not independently associated with adverse cardiac or aortic events. ConclusionsMitral phenotypes are more prevalent in individuals with PV in TGF-{beta} pathway genes, particularly SMAD3, and are associated with adverse aortic and cardiac events. Because congenital mitral disease may be the primary presenting feature of SMAD3 PV, genetic testing for HTAD should be considered for such individuals, especially if they also have a family history of HTAD. Clinical/Research PerspectiveO_ST_ABSWhat Is New?C_ST_ABS1) Mitral regurgitation, mitral valve prolapse, and mitral annular disjunction (MAD) are common in heritable thoracic aortic disease (HTAD) caused by pathogenic variants (PV) in TGF-{beta} pathway genes (SMAD3, TGFBR1, TGFBR2, TGFB2, or TGFB3) and are associated with adverse cardiac events. 2) Pathological mitral phenotypes are particularly prominent in people with SMAD3 PV and may be the presenting feature of HTAD in some cases. What Are the Clinical Implications?3) Pathological mitral valve phenotypes may identify a high-risk subgroup of HTAD cases with more frequent adverse cardiovascular events. Because congenital mitral disease may be the primary presenting feature of SMAD3 PV, genetic testing for HTAD should be considered for such individuals, especially if they also have a family history of HTAD.

BackgroundAccurate aortic stenosis (AS) phenotyping requires access to multimodality imaging which has limited availability. The Digital Aortic Stenosis Severity Index (DASSi), an AI biomarker of AS-related remodeling on 2D echocardiography, predicts AS progression independent of Doppler measurements. Whether DASSi-enhanced echocardiography provides a scalable alternative to multimodality AS imaging remains unknown. We sought to evaluate the ability of DASSi to define personalized AS progression profiles and validate its performance against multimodality imaging features of functional, structural, and biological disease severity. MethodsIn the SALTIRE-2 trial of participants with mild-or-moderate AS, we performed blinded DASSi measurements (probability of severe AS, 0-to-1) on baseline transthoracic echocardiograms. We evaluated the association between baseline DASSi and (i) disease severity by hemodynamic (peak aortic valve velocity [AV-Vmax]), structural (CT-derived aortic valve calcium score [AVCS]) and biological features ([18F]sodium fluoride [NaF] uptake on Positron Emission Tomography-CT), (ii) disease progression (change in AV-Vmax and AVCS), and (iii) incident aortic valve replacement (AVR). We used generalized linear mixed, or Cox models adjusted for risk factors and aortic valve area, as appropriate. ResultsWe analyzed 134 participants (72 [IQR: 69-78] years, 27 [20.1%] women) with a mean baseline DASSi of 0.51 (standard deviation [SD]: 0.19). DASSi was independently associated with disease severity: each SD increase was associated with higher AV-Vmax (+0.21 [95%CI: 0.12-0.30] m/sec), AVCS (+284 [95%CI: 101-467] AU) and [18F]NaF TBRmax (+0.17 [95%CI: 0.04-0.31]). Higher DASSi was also associated with disease progression by Doppler (AV-Vmax) and CT (AVCS) at 24 months (pinteraction for DASSi (x) time<0.001), and future AVR (75 events over 5.5 [IQR: 2.4-7.2] years, adj.HR 1.47 [95%CI: 1.12-1.94] per SD). ConclusionsDASSi is associated with functional, structural and biological features of AS severity as well as disease progression and outcomes. DASSi-enhanced echocardiography provides a readily accessible alternative to multimodality imaging of AS which has potential value both in clinical practice and as a clinical trial biomarker.

BackgroundFamilial dilated cardiomyopathy (DCM) is characterized by marked variability in phenotypic penetrance. The extent to which this is determined by patient-specific environmental factors is unknown. MethodsA retrospective longitudinal cohort study was performed in families with DCM-causing genetic variants. Environmental factors were classified into two subsets based on evidence for a causal link to depressed myocardial contractility, termed (1) DCM-promoting factors and (2) heart failure (HF) comorbidities. These factors were correlated with DCM diagnosis, disease trajectory, and adverse events. Results105 probands and family members were recruited: 51 genotype-positive, phenotype-positive (G+P+), 24 genotype-positive, phenotype-negative (G+P-), and 30 genotype-negative, phenotype-negative (G-P-). Baseline characteristics were similar between the 3 genotype groups. DCM-promoting environmental factors (eg. alcohol excess) were enriched in G+P+ individuals compared to G+P-(P<0.001) and G-P-(P=0.003) and were significantly associated with age at DCM onset (HR 2.01, P=0.014). HF comorbidities (eg. Diabetes) had a similar prevalence in G+P+ and G-P-but were significantly reduced in the G+P-group. Fluctuations in left ventricular ejection fraction during follow-up were linked to changes in environmental factors in 35/45 (78%) of instances: 32 (91%) of these were DCM-promoting factors. HF comorbidities, but not DCM-promoting factors, were associated with adverse events in G+ individuals (OR 4.9, P=0.004). ConclusionWe identified distinct subsets of environmental factors that affect DCM penetrance and adverse outcomes respectively. Our data highlight DCM-promoting environmental factors as key determinants of penetrance and disease trajectory. Collectively, these findings provide a new framework for risk factor assessment in familial DCM and have important implications for clinical management.

Background: The clinical significance of sarcomere variants of uncertain significance (VUS) in hypertrophic cardiomyopathy (HCM) remains unclear, and VUS are currently regarded as clinically non-actionable despite their increasing prevalence. This study aimed to evaluate genotype?phenotype and genotype?outcome associations according to variant pathogenicity in patients with HCM, with a particular focus on the clinical relevance of sarcomere VUS. Methods: This multicenter retrospective cohort study included 438 patients with HCM who underwent next-generation sequencing-based genetic testing at two tertiary hospitals. Patients were classified into three groups: pathogenic or likely pathogenic (P/LP) variants, VUS, and no sarcomere mutations. Clinical characteristics, imaging phenotypes, and outcomes were compared across groups. The primary endpoint was a composite of cardiovascular death, aborted sudden cardiac death, appropriate implantable cardioverter-defibrillator therapy, and heart transplantation. Time-to-event analyses were performed using Kaplan-Meier methods and Cox proportional hazards models with Firth's penalized partial likelihood approach. Results: P/LP variants were identified in 171 patients (39.0%) and sarcomere VUS in 159 patients (36.3%). Patients with VUS demonstrated intermediate clinical and phenotypic features between P/LP carriers and genotype-negative patients. Kaplan?Meier analysis showed a graded difference in event-free survival across variant classifications. While VUS were not independently associated with adverse outcomes when modeled as a categorical variable, increasing pathogenicity from genotype-negative to VUS and P/LP variants was associated with a stepwise increase in risk of the primary endpoint (hazard ratio 2.05, 95% confidence interval 1.11?4.16 p=0.019). Identified VUS were preferentially enriched in Z-disc and giant sarcomere scaffolding proteins. Conclusion: Sarcomere VUS represent intermediate characteristics along a continuum of sarcomere dysfunction, associated with distinct phenotypic features and clinical outcomes compared with both P/LP variants and the absence of sarcomere mutations. These findings suggest that sarcomere VUS may not be entirely clinically neutral and should be interpreted within a broader genetic and structural context in patients with HCM.

Background. Hypertrophic cardiomyopathy (HCM) is a clinically variable disease in terms of onset and progression. Pathogenic MYBPC3 variants account for a substantial proportion of HCM diagnoses. This study sought to identify protein biomarkers associated with HCM severity. Methods. Olink-assayed plasma proteins of 144 MYBPC3 pathogenic variant carriers were tested for associations with HCM severity based on HCM diagnostic criteria (unaffected, mildly, or severely affected). The UK Biobank was used to replicate the identified proteins through considering time to onset of HCM (67 cases), cardiomyopathy (156 cases),and associations with cardiac MRI derived left ventricular maximum wall thickness (6,492 participants). Replicated proteins were further prioritised based on cardiac tissue expression and druggability, and annotated using pathway enrichment and association with onset of: heart failure (HF), dilated cardiomyopathy (DCM), sudden cardiac arrest (SCA), and ventricular arrhythmias (VA). Results. Among pathogenic MYBPC3 variant carriers, we identified 27 proteins associated with HCM severity. We independently replicated 21 proteins in the UK Biobank. Of the five prioritised proteins (NT-proBNP, GDF-15, FGF-23, ADM, and NCAM1), all but NT-proBNP were targeted by drugs with repurposing potential. The replicated proteins additionally associated with the incidence of HF (n=5), DCM (n=4), SCA (n=4), and VA (n=4). Conclusion. This study replicated 21 and prioritised five proteins associated with HCM severity in pathogenic MYBPC3 variant carriers. Replication in unselected HCM suggests the prioritised proteins are associated with HCM independent of genotype, providing important leads for plasma-based markers for diagnoses, disease monitoring, and drug targets.

IntroductionCalcific aortic valve disease (CAVD) is the most common valvular disorder in older adults, characterized by progressive fibrosis, calcification, and impaired blood flow. Despite its growing burden, no effective pharmacological treatments exist. Inflammation and epigenetic dysregulation are increasingly recognized as central to CAVD pathogenesis. This study aimed to identify key inflammatory genes and regulatory mechanisms contributing to disease development. MethodsWe performed a meta-analysis of aortic valve transcriptomic datasets, focusing on inflammation-related genes, to identify differentially expressed genes (DEGs) in CAVD. Blood-derived expression quantitative trait loci (eQTL) and DNA methylation QTL (mQTL) data were integrated with CAVD genome-wide association study (GWAS) results (FinnGen database) using a three-step summary data-based Mendelian randomization (SMR) framework. Additionally, we combined aortic eQTL data and inflammatory mediator GWAS to assess tissue-specific regulatory interactions through SMR and co-localization analyses. ResultsFifty-seven inflammation-related DEGs were identified, enriched in immune cells from patients with CAVD. Multi-omics integration prioritized nine causal genes in blood, including PPARG, TLR2, LTA, TNF, C4A, IL6, RELA, C3, and TGF{beta}1. Among these, TNF and TGF{beta}1 were strongly associated with increased CAVD risk. In aortic tissue, SMR and co-localization analyses revealed TLR2, C4A, and AGER as key genes linked to inflammatory pathways, highlighting a potential gene-immune axis in disease progression. ConclusionsOur integrative multi-omics analysis reveals that calcific aortic valve disease (CAVD) is driven by genetically and epigenetically regulated inflammatory pathways. We identify TNF and TGF{beta}1 as epigenetically controlled causal drivers, while AGER, C4A, and TLR2 emerge as tissue-specific mediators of aortic inflammation. These findings establish a causal link between immune dysregulation and CAVD pathogenesis, highlighting promising targets for biomarker development and precision therapies aimed at interrupting disease progression.

BackgroundLeft ventricular noncompaction (LVNC) is a prevalent cardiomyopathy associated with excessive trabeculation and thin compact myocardium. Patients with LVNC are vulnerable to cardiac dysfunction and at high risk of sudden death. Although sporadic and inherited mutations in cardiac genes are implicated in LVNC, understanding of the mechanisms responsible for human LVNC is limited. MethodsWe screened the complete exome sequence database of the Pediatrics Cardiac Genomics Consortium and identified a cohort with a de novo chromodomain helicase DNA-binding protein 4 (CHD4) proband, CHD4M202I, with congenital heart defects. We engineered a patient-specific model of CHD4M202I (mouse CHD4M195I). Histological analysis, immunohistochemistry, flow cytometry, transmission electron microscopy, and echocardiography were used to analyze cardiac anatomy and function. Ex vivo culture, immunopurification coupled with mass spectrometry, transcriptional profiling, and chromatin immunoprecipitation were performed to deduce the mechanism of CHD4M195I-mediated ventricular wall defects. ResultsCHD4M195I/M195I mice developed biventricular hypertrabeculaion and noncompaction and died at birth. Proliferation of cardiomyocytes was significantly increased in CHD4M195I hearts, and the excessive trabeculation was associated with accumulation of extracellular matrix (ECM) proteins and a reduction of ADAMTS1, an ECM protease. We rescued the hyperproliferation and hypertrabeculation defects in CHD4M195I hearts by administration of ADAMTS1. Mechanistically, the CHD4M195I protein showed augmented affinity to endocardial BRG1. This enhanced affinity resulted in failure of derepression of Adamts1 transcription such that ADAMTS1-mediated trabeculation termination was impaired. ConclusionsOur study reveals how a single mutation in the chromatin remodeler CHD4, in mice or humans, modulates ventricular chamber maturation and that cardiac defects associated with the missense mutation CHD4M195I can be attenuated by the administration of ADAMTS1. Clinical PerspectiveO_ST_ABSWhat Is New?C_ST_ABSO_LIA patient-specific mouse model of CHD4M202I develops ventricular hypertrabeculation and dies at birth. C_LIO_LIProliferation of cardiomyocytes is significantly enhanced in CHD4M195I mice. C_LIO_LIADAMTS1 is significantly downregulated in CHD4M195I mice. C_LIO_LIClose interaction between CHD4M195I and BRG1 robustly and continuously represses Adamts1 transcription, which impairs ADAMTS1-mediated termination of trabeculation in the developing mutant heart. C_LI What Are the Clinical Implications?O_LIThis study provides a unique mouse model of ventricular noncompaction cardiomyopathy that faithfully reflects human patients genetic condition without disturbing the target genes expression and localization. C_LIO_LITranscriptional repression of ECM protease ADAMTS1 by CHD4-BRG1 interaction is detrimental to ventricular wall maturation; maintaining appropriate ADAMTS1 levels in the heart could be a promising therapeutic approach for treating ventricular noncompaction cardiomyopathy. C_LI

Transthyretin cardiac amyloidosis (ATTR-CA) is a treatable cause of heart failure with a hereditary form that disproportionally affects patients of West African ancestry. The clinical management of ATTR-CA has dramatically changed in the past five years, with rapidly evolving diagnostic approaches and life-prolonging therapies. The TTR variant c.424G>A, p.V142I (aka V122I) is pathogenic and occurs in 3-4% of individuals of West African ancestry. Despite its high frequency, V142I ATTR-CA is often unrecognized due to variable clinical penetrance, limited knowledge, and lack of inexpensive non-invasive diagnostic tests. Currently unknown is which TTR V142I carriers will progress to heart failure and at what age. Here we studied the prevalence of TTR V142I among a random cohort of African-American patients enrolled in the Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist Trial (TOPCAT). Three of the 26 HFpEF patients (11.5%) studied carried the pathogenic TTR V142I variant. While we cannot conclude at this point that TTR V142I was the underlying cause of the clinical phenotype in these patients, our results suggest that rapid TTR V142I genotyping, in combination with heart imaging, could have immediate clinical utility for identifying under-/mis-diagnosed HFpEF patients.

Aims: Assessment of treatment response in HFrEF has largely relied on left ventricular (LV)-centric parameters, yet the left atrium (LA) plays a central role in modulating LV filling and reflects the cumulative hemodynamic burden. Whether discordant recovery between LV and LA function carries distinct prognostic implications in patients treated with ARNI-based therapy remains unknown. Methods and results: From the multicenter STRATS-HF-ARNI registry, 1,182 patients with HFrEF who underwent serial echocardiography at baseline and one-year follow-up were included. Patients were classified into four strain recovery phenotypes according to the direction of change in LVGLS and LASr at one year: Group A, concordant recovery (57.4%); Group B, discordant atrial non-recovery (11.2%); Group C, discordant ventricular non-recovery (15.6%); and Group D, concordant non-recovery (16.0%). Clinical outcomes included all-cause mortality, cardiovascular mortality, and HF hospitalization. Despite achieving LV functional improvement, Group B exhibited persistent LASr deterioration, accompanied by less favorable hemodynamic trajectories compared with Group A. On multivariable Cox regression, Group B was associated with significantly higher risks of all-cause mortality (adjusted hazard ratio [aHR] 3.53, 95% confidence interval [CI] 1.60-7.79) and cardiovascular mortality (aHR 5.68, 95% CI 1.91-16.92), comparable to Group D. Group C demonstrated higher HF hospitalization risk (aHR 2.25, 95% CI 1.31-3.86). The adverse prognostic impact of discordant atrial non-recovery was consistently observed across subgroups stratified by baseline LVGLS and LASr levels. Conclusion: In HFrEF patients treated with ARNI-based therapy, persistent LA dysfunction despite LV functional improvement identifies a high-risk phenotype comparable to concordant non-recovery. These findings suggest that concurrent assessment of LV and LA strain may provide incremental prognostic value beyond LV-centric metrics alone.

STRUCTURED ABSTRACTO_ST_ABSBackgroundC_ST_ABSAortic stenosis (AS) accounts for substantial global morbidity and premature mortality even in moderate AS (Mod-AS). The mechanisms for this adverse prognosis in Mod-AS, however, remain poorly understood, although the myocardial remodeling response is thought to be critical. We aimed to prospectively assess myocardial remodeling, perfusion and energetics differences in Mod-AS and severe AS (Severe-AS). MethodsFifty-two Severe-AS and 25 Mod-AS patients and 18 demographically-matched controls underwent cardiovascular magnetic resonance and phosphorus-magnetic resonance spectroscopy to define left ventricular (LV) mass and function, global longitudinal shortening (GLS), rest and adenosine-stress myocardial blood flow (MBF), myocardial perfusion reserve (MPR), layer-specific perfusion metrics (subendocardial [Endo], subepicardial [Epi] MBF and MPR, and Endo-to Epi-MBF ratio [Endo/Epi]), myocardial scar on late gadolinium enhancement (LGE) imaging, and myocardial energetics (phosphocreatine:ATP ratio [PCr/ATP]). ResultsCompared to controls, from Mod-AS to Severe-AS there was a progressive increase in LV concentricity (LV-mass/LV-end-diastolic-volume)(controls:0.58[0.54,0.62], Mod-AS:0.74[0.64,0.84], Severe-AS:0.89[0.83,0.95]g/mL; P<0.0001), LV mass-index (controls: 46[40,51], Mod-AS: 58[51,65], Severe-AS: 70[65,75]g/m2; P<0.0001) and stepwise decline in GLS (controls:19.9[17.6,22.2], Mod-AS:17.7[16.6,18.8], Severe-AS:13.4[12.5,14.4]%; P<0.0001) with significant differences between Mod-AS and Severe-AS for all three comparisons. Both stress MBF (controls:2.1[1.9,2.3], Mod-AS:1.9[1.6,2.2], Severe-AS:1.3[1.2,1.5]ml/min/g; P<0.0001) and MPR (controls:3.3[2.8,3.6], Mod-AS:2.8[2.4,3.2], Severe-AS:1.9[1.8,2.1]; P<0.0001) were only significantly reduced in Severe-AS compared to controls, with significant differences also detected between Mod-AS and Severe-AS. However, stress-endo-MBF (controls:2.0[1.8,2.3], Mod-AS:1.7[1.5,2.0], Severe-AS:1.2[1.1,1.3] ml/min/g; P<0.0001), stress-Endo/Epi (controls:1.00[0.93,1.07], Mod-AS:0.87[0.80,0.94], Severe-AS:0.81[0.75,0.82]; P<0.0001), rest-Endo/Epi (controls:1.12[1.10,1.14], Mod-AS:1.06[1.03,1.09], Severe-AS:1.03[1.02,1.06]; P<0.0001) and endo-MPR (controls:3.2[2.7,3.6], Mod-AS:2.5[2.1,2.9], Severe-AS:1.7[1.5,1.8]; P<0.0001) were all significantly reduced in both Mod-AS and Severe-AS. Compared to controls, both AS groups showed significantly lower PCr/ATP (controls:2.2[2.0,2.3], Mod-AS:1.8[1.6,2.0], Severe-AS:1.7[1.6,1.8]; P<0.0001) and shorter 6-minute-walk-distance (controls:525[495,555], Mod-AS:420[375,465]m, Severe-AS:345[248,420]m; P<0.0001). Only the Severe-AS group had evidence of non-ischemic myocardial scarring on LGE (2.9[0.0,6.2]%), which was detected in 65% (n=34) of patients. Neither group had evidence of ischemic scar. The AS severity (peak aortic valve velocity) correlated with the stress-MBF (r=-0.45, P=0.0003), MPR (r=-0.44, P=0.0005) and GLS (r=-0.47, P=0.0001). ConclusionsModerate and severe AS are both associated with cardiac concentric hypertrophy, reductions in myocardial energetics, subendocardial hypoperfusion, and limitations in exercise distance. Patients with Severe-AS exhibit a more pronounced phenotype with worse LV hypertrophy, contractile dysfunction and myocardial scarring compared to patients with Mod-AS. CLINICAL PERSPECTIVESWhat is new: O_LIPatients with moderate aortic stenosis show cardiac concentric hypertrophy, reduction in myocardial energetics, shorter 6-minute walk distance compared to age-and sex-matched controls, but no evidence of myocardial scarring. C_LIO_LIGlobal myocardial perfusion metrics of rest and stress myocardial blood flow or myocardial perfusion reserve do not show significant reductions in patients with moderate aortic stenosis. C_LIO_LIThe perfusion dynamics of the epicardial and endocardial layers differ in the presence of moderate aortic stenosis, with significant reductions in endocardial stress myocardial blood flow, rest and stress endocardial to epicardial myocardial blood flow ratio, and endocardial as well as epicardial myocardial perfusion reserve compared to controls. C_LI What Are the Clinical Implications?O_LIWhile milder compared to that seen in severe aortic stenosis, the degree of adverse myocardial remodeling and subendocardial hypoperfusion associated with moderate aortic stenosis may be clinically important for the cardiovascular clinical outcomes in patients with moderate aortic stenosis. C_LIO_LILarger prospective serial studies and randomized trials are needed to better understand the mechanisms of high cardiovascular and all-cause mortality rates in patients with moderate aortic stenosis. C_LI

AimsHypertrophic cardiomyopathy (HCM) is an inherited cardiomyopathy mainly caused by pathogenic variants in MYBPC3 and MYH7, encoding myosin binding protein C3 and myosin heavy chain 7, respectively. These variants can cause increased actin-myosin crossbridge cycling resulting in ventricular hypercontractility. Little is known about genotype-specific differences. Mice lacking Mybpc3 exhibited reduced left ventricular ejection time (LVET). In this study we tested whether LVET is specifically altered in patients carrying MYBPC3 variants by retrospective echocardiographic analysis in two genotype-defined HCM cohorts. Methods and resultsLVET was measured by echocardiography and adjusted for heart rate (LVET index, LVETI) in 173 patients carrying MYBPC3 or MYH7 pathogenic variant. There was a discovery cohort (Hamburg; 46 MYBPC3, 31 MYH7) and a validation cohort ("Valsartan in Attenuating Disease Evolution in Early Sarcomeric HCM"; 55 MYBPC3, 41 MYH7). Data were compared with 44 healthy controls from Hamburg. Variant carriers were stratified for overt (G+LVH+) or subclinical left ventricular hypertrophy (G+LVH-). LVETI was lower in MYBPC3 and higher in MYH7 G+LVH+ patients than in controls in the discovery, validation and pooled cohorts (pooled: 385 {+/-} 23 ms MYBPC3, 436 {+/-} 38 ms MYH7, 411 {+/-} 15 ms controls). Similar findings were seen in G+LVH-. ConclusionThe data suggest that variants in MYBPC3 and MYH7 result in distinct biophysical consequences, which can be detected by measuring LVETI in patients. The findings may have implications for potential genotype-specific differences in response to therapies targeting sarcomere function.

BackgroundPulmonary hypertension due to heart failure with preserved ejection fraction (PH-HFpEF) is a highly heterogeneous disease associated with right ventricular (RV) failure and adverse outcomes. Current diagnostic tools inadequately characterize pulmonary vascular disease and RV dysfunction, limiting treatment precision. We hypothesized that deep phenotyping--including invasive hemodynamics, advanced imaging, and myocardial transcriptomics--would identify high-risk PH-HFpEF phenotypes with distinct clinical, physiologic, and molecular characteristics. Methods42 PH-HFpEF participants (and 25 pre-capillary PH participants, as a comparison group) underwent clinical evaluation, echocardiography, cardiac MRI (cMRI), and invasive cardiopulmonary exercise testing (iCPET). K-means clustering considering clinical, iCPET, and cMRI data stratified participants into distinct clusters (phenogroups). A subset underwent further characterization by invasive pulmonary vascular mechanics (n=17 PH-HFpEF, n=5 pre-capillary PH) and 4D flow cMRI (n=10 PH-HFpEF, n=5 pre-capillary PH). Endomyocardial biopsies from 10 PH-HFpEF participants were analyzed using long-read RNA-sequencing for differential gene and transcript expression. ResultsClustering revealed two PH-HFpEF phenogroups with significantly different outcomes at one-year follow-up (HR=11.96, CI: 2.66-53.86). High-risk participants had greater left ventricular mass, reduced RV ejection fraction, worse exercise-induced PH, impaired gas exchange ({downarrow}peak oxygen consumption, {uparrow}slope of minute ventilation/carbon dioxide production), and lower myocardial strain. Pulmonary vascular mechanics showed higher proximal pulmonary artery stiffness ({uparrow}characteristic impedance), increased RV energy expenditure ({uparrow}compression waves), and abnormal distal vascular reflections ({downarrow}diastolic reflection index) in the high-risk group. 4D flow MRI revealed disturbed flow in pulmonary vasculature (both arteries and veins) in high-risk participants. Transcriptomic analysis implicated differences in post-transcriptional RNA processing and translational control, as well as mitochondrial function, in phenotypic divergence between these HFpEF subgroups. In particular, differential transcript usage for the TTN gene, encoding the giant sarcomeric protein titin, may be particularly relevant to elevated myocardial stiffness, which worsens vascular remodeling and precipitates RV dysfunction and failure. ConclusionsIn PH-HFpEF, unsupervised clustering using deep physiologic and imaging data identified a high-risk group with impaired RV function and unique transcriptomic profiles. Our findings suggest that proximal and distal pulmonary vascular remodeling, as well as differences in titin isoform expression, may underlie RV failure in this phenogroup. This comprehensive approach provides a framework for mechanistically driven precision medicine strategies in PH-HFpEF. Clinical perspectives1. What is new?O_LIUnsupervised clustering integrating exercise hemodynamics, cardiac MRI, and clinical features revealed a distinct PH-HFpEF subgroup at significantly higher risk for adverse outcomes (HR = 11.96), independent of traditional IpcPH/CpcPH classification. C_LIO_LIInvasive wave mechanics (impedance and wave separation analyses) and non-invasive 4D flow cardiopulmonary MRI reveal unique patterns of proximal stiffness, RV energy inefficiency, and abnormal distal reflections in high-risk PH-HFpEF, providing insights into segmental vascular dysfunction. C_LIO_LILong-read RNA sequencing of endomyocardial biopsies from PH-HFpEF patients revealed distinct transcriptomic signatures between high- and low-risk PH-HFpEF phenogroups. C_LIO_LILong-read RNA-seq identified distinct transcript usage of gene TTN, encoding a giant sarcomeric protein (titin) that is a key determinant for myocardial stiffness, suggesting a potential underlying mechanism for RV dysfunction in PH-HFpEF. C_LI 2. What are clinical implications?O_LIThese findings offer a framework for more refined patient classification beyond traditional PVR-based methods, which may improve identification of high-risk individuals who require closer monitoring or targeted therapy. C_LIO_LIThe integrative approach highlights titin isoform imbalance and vessel-specific stiffness as potential therapeutic targets, supporting the development of biology-informed, phenotype-specific interventions for PH-HFpEF with RV dysfunction. C_LI

BackgroundFabry disease (FD) is an X-linked disorder with progressive myocardial sphingolipid deposition, causing premature cardiovascular morbidity and mortality. Advanced electrocardiography (A-ECG) has the potential to predict cardiac involvement. ObjectivesTo evaluate the predictive power of A-ECG in identifying: 1) early cardiac involvement defined as low myocardial T1 on cardiovascular magnetic resonance (CMR), 2) adverse cardiovascular outcomes, and 3) heart age. MethodsIn this longitudinal multi-centre study, patients underwent same-day CMR and digital ECG, analysed using in-house software, including conventional ECG, derived vectorcardiographic, and singular value decomposition measures of waveform complexity parameters. Significant A-ECG variables were identified using stepwise forward regression and incorporated in a multivariable logistic regression A-ECG score. A Youden index was applied to identify best threshold score and bootstrapping performed to calculate the area under the receiver operating characteristics curve (AUC), sensitivity, specificity, and 95% confidence intervals (CI). ResultsIn 155 patients (40% male, age 46{+/-}14 years, 39% on enzyme replacement therapy), left ventricular mass was higher in males compared to females (106 vs. 59 g/m2, p<0.001), 80% had low native T1, and 51% (70/136) had late gadolinium enhancement. A-ECG heart age was higher than chronological age in all patients (57{+/-}20 vs. 46{+/-}14 years, p<0.001). The heart age gap was strongly associated with T1 lowering and progressive LVH. Multivariable A-ECG scores for detecting low T1 had an AUC [95%CI] of 0.82 [0.75-0.89], sensitivity 72 [55-95] %, and specificity 85 [66-71] %; any arrhythmia 0.89 [0.82-0.95], 82 [68-94] %, 88 [70-96] %; or atrial fibrillation 0.89 [0.80-0.96], 92 [77-100] %, 83 [76-92] %, respectively. No predictors of heart failure hospitalisation or mortality were found. ConclusionA-ECG analysis has good diagnostic performance for predicting low native T1 and the occurrence of arrhythmias in Fabry disease but not for heart failure hospitalisation or death.

BackgroundMyocardial 18fluorodeoxyglucose (18FDG)-avidity is frequently seen in patients with genetic cardiomyopathy (CMP), as well as a growing "idiopathic 18FDG-avidity" group of genotype-negative patients who do not clearly have cardiac sarcoidosis (CS). ObjectivesTo determine the prognostic implications of 18FDG-avidity in patients with and without genetic CMP, and the effects of immunosuppression in the latter. MethodsThis multicenter, retrospective study included all patients who were referred for both 18FDG-PET and CMP genetic testing. Patients with acute myocarditis, biopsy-proven sarcoidosis or extracardiac 18FDG-avidity were excluded. We investigated heart failure (HF) composite (left ventricular assist device, heart transplant, HF hospitalization, death) and arrhythmia composite (sustained ventricular arrhythmias (VT/VF), atrio-ventricular block, death) outcomes using survival analysis including Cox proportional hazards modeling and inverse probability of treatment weighting (IPWT). ResultsAmong 372 patients, 142 (38%) were 18FDG-avid. Prevalence of genetic CMP among 18FDG-avid patients (12%) was similar to that of 18FDG-negative patients (19%, p=0.07). 18FDG-avidity was associated with increased risk of HF composite (HR 1.69 (1.04-2.75), p=0.034) and arrhythmia composite (HR 1.63 (1.1-2.4), p=0.014) outcomes compared to 18FDG-negative patients. However, these associations were present only in genotype-negative patients, and not in genetic CMP. After IPWT, immunosuppression of 18FDG-avid patients (n=49) was not associated with a reduction in HF (HR 3.31 (1.25, 8.77), p=0.016) or arrhythmia composite outcomes (HR 1.61 (0.79, 3.25), p=0.19) compared with those who were not immunosuppressed (n=93). ConclusionsMyocardial-only 18FDG-avidity is only associated with adverse HF and arrhythmia outcomes in genotype-negative patients who do not clearly have CS. IST does not seem to modify the disease course, suggesting that not all myocardial 18FDG uptake reflects clinically significant inflammation.

BackgroundDilated cardiomyopathy (DCM) represents the most prevalent form of pediatric cardiomyopathy. However, the characteristics and etiology of this condition across different pediatric age groups remain incompletely elucidated. Methods and resultsData from 88 pediatric patients aged <14 years diagnosed with primary DCM between January 2021 and December 2023 were retrospectively retrieved from the institutional database and analyzed. Patients were stratified into two groups using a 3-year age cutoff. Clinical characteristics, echocardiographic parameters, and biomarkers were documented for each patient to facilitate subsequent analysis. Of these patients, 11 underwent heart transplantation and additional transcriptomic and proteomic analyses were conducted to identify differentially expressed genes (DEGs) and proteins (DEPs). Additionally, cardiac magnetic resonance imaging was utilized to evaluate myocardial fibrosis. Statistically significant disparities were observed between the two age groups with respect to clinical characteristics and clinical outcomes. Patients in the [&le;]3-year-old group exhibited a more favorable prognosis. Multi-omics integrative analysis revealed that genes associated with inflammatory responses and energy metabolism impairment--notably PDK4, CHI3L1, ZBP1 and ANXA1--were enriched in the younger group. In contrast, myocardial inflammation and fibrosis were the predominant features in the older group, as evidenced by the significant upregulation of COL11, CTGF, RO60 and MAT2B. ConclusionsAt both the transcriptomic and translational levels, we uncovered global variations in miRNAs and proteins associated with DCM, following stratification of patients by the 3-year age cutoff. Specifically, energy metabolism dysregulation plays a pivotal role in younger pediatric patients, whereas irreversible myocardial fibrosis may underlie the suboptimal response to conservative therapy in older pediatric patients.