Circulation

Background. Septal reduction therapy (SRT) is recommended in drug-refractory, symptomatic obstructive hypertrophic cardiomyopathy (oHCM). We evaluated whether aficamten, a novel cardiac myosin inhibitor, can reliably transition guideline-eligible SRT candidates to ineligibility, and the associated safety profile of aficamten in this group. Methods. We analyzed participants with oHCM enrolled in FOREST-HCM (NCT04848506), the long-term open-label extension study of aficamten, from 28 May 2021 to 9 May 2025. Results. Three hundred and fifteen patients were included, of whom 104 met 2024 ACC/AHA guideline criteria for SRT eligibility at baseline. The SRT-eligible cohort was predominantly female (57%), with mean resting and Valsalva left ventricular outflow tract (LVOT) gradients of 63 {+/-} 39 and 109 {+/-} 42 mmHg, and all were in New York Heart Association (NYHA) class III. All baseline SRT-eligible patients became SRT-ineligible with aficamten therapy during study follow-up over a median of 42 days (IQR: 17, 49), except for one participant who withdrew from the study to pursue SRT (total of 3 participants withdrew). After dose titration, 3/104 (2.9%) remained guideline-eligible; by week 72 no patients met eligibility criteria. At maintenance, resting and Valsalva LVOT gradients improved by a least-squares mean of ?41 mmHg ([95% CI ?44 to ?37]; P<0.0001) and ?56 mmHg ([95% CI ?62 to ?51]; P<0.0001), respectively. Relative to baseline, NT-proBNP improved by 77% (95% CI 74 ? 80%), high-sensitivity cardiac troponin I decreased by 38% (95% CI 30 ? 46%), KCCQ-CSS improved by a mean of 20.2 (SD 19.3) points, and 95.2% of SRT-eligible patients had improved by ?1 NYHA class. Overall, the safety profile was favorable, with 2 occurrences of left ventricular ejection fraction (LVEF) < 50% over 193.7 patient-years of follow-up (1 event per 100 patient-years), managed by down-titration. There were no baseline SRT-eligible patients who died or developed LVEF <40%. Conclusions. Aficamten resolved guideline eligibility for SRT in nearly all baseline-eligible patients, with rapid and durable improvements in hemodynamics, symptoms, biomarkers and health status sustained for up to 3.5 years. Instances of LVEF <50% were rare and without clinical sequelae. These data support aficamten as a safe and effective alternative to SRT in oHCM.

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.

Importance: Cardiac conduction disorders have traditionally been regarded as a secondary manifestation of underlying structural heart diseases. However, isolated conduction disorders may precede the onset of heart failure (HF) suggesting shared mechanisms. Objective: To evaluate the prevalence and clinical significance of pathogenic/likely pathogenic (P/LP) rare variants in cardiomyopathy genes among individuals with conduction disorders. Design, Setting, and Participants: Biobank analysis of 192,834 participants with whole genome sequence data from Vanderbilt's BioVU and 353,092 participants from the All of Us Research Program (AoU). Participants with primary conduction disorder (left bundle branch block [LBBB], right bundle branch block [RBBB], high-grade atrioventricular block [AVB]) were identified after excluding secondary causes. Exposures: P/LP variants in cardiomyopathy genes. Main Outcomes and Measures: Primary outcome was P/LP carrier status by age and HF status. Secondary outcomes included incident HF and composite ventricular arrhythmias/sudden cardiac death/mortality (VA/SCD/mortality). Results: Among 16,959 participants with conduction disorders in BioVU and 13,442 in AoU, 432 (2.6%) and 206 (1.5%) were P/LP carriers, respectively. Conduction disorder was independently associated with carrier status (BioVU p<0.001; AoU p=0.005). Carrier probability varied by age at conduction disorder onset and HF status. Among participants with HF at age 30 years, predicted carrier probability for LBBB was 7.5% in BioVU and 20.2% in AoU; for high-grade AVB, 7.7% and 8.5%, respectively, compared with 3.7% and 2.9% among those with HF without conduction disorder. P/LP carrier status among participants with conduction disorders was associated with increased risk of incident HF (BioVU p<0.001; AoU p<0.001) and ventricular arrhythmia/sudden death/mortality (BioVU p<0.001; AoU p<0.001). Carriers also demonstrated increased susceptibility to conduction disorder following HF diagnosis, including more than two-fold higher risk of third-degree AVB (BioVU aOR 2.48, 95% CI 1.85-3.32; AoU aOR 2.26, 95% CI 1.35-3.80). Conclusions: Adults with primary conduction disorders have an increased prevalence of P/LP variants in cardiomyopathy genes, which is most pronounced with diagnoses at early ages of adulthood. Furthermore, there is evidence of an interaction between P/LP carrier status and conduction disorder to increase HF risk and composite cardiovascular outcomes, underscoring the potential role of genetic evaluation in patients with primary conduction disorders to inform long-term outcomes.

Background and Aims Genetic testing in dilated cardiomyopathy (DCM) guides risk stratification and family screening. Likely pathogenic or pathogenic (LP/P) variants are identified in approximately one-third of patients, leaving many without a genetic diagnosis. Cohort studies suggest that "gene-elusive" patients have a lower risk of adverse events. This study aims to better characterise this group and identify factors associated with adverse outcomes. Methods Consecutive and unrelated DCM patients undergoing genetic testing and returning no LP/P variants were retrospectively recruited and compared to two control cohorts of DCM patients carrying LP/P variants in LMNA and TTN for a primary composite endpoint of end-stage heart failure (ESHF) or malignant ventricular arrhythmia (MVA). Results Among patients without prior MVA, the composite endpoint occurred in 36/423 (8.5%) gene-elusive, 14/39 (35.9%) LMNA and 11/100 (11%) TTN cardiomyopathy patients (log-rank p<0.001 for LMNA vs gene-elusive and LMNA vs TTN; p=0.96 for TTN vs gene-elusive). For gene-elusive patients, lower left ventricular ejection fraction, larger left ventricular internal diameter in diastole, absence of LBBB and ventricular ectopy on ECG were independent predictors of the primary endpoint. Gene-elusive patients with LBBB had less atrial arrhythmia and a lower burden of ventricular ectopy at baseline and a low risk of the primary composite endpoint (HR 0.3 [0.1-0.8], p-value 0.01). Conclusions Gene-elusive DCM patients have a risk of adverse events similar to TTN cardiomyopathy. Gene-elusive patients with LBBB form a particularly low-risk subgroup, likely reflecting a distinct aetiology of left ventricular systolic dysfunction.

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

Background: Aspirin-free P2Y12-inhibitor monotherapy after percutaneous coronary intervention (PCI) is an alternative to dual antiplatelet therapy (DAPT), but the evidence rests largely on full-dose ticagrelor in acute coronary syndrome and on designs retaining a DAPT run-in; East-Asian patients may not require the same antithrombotic intensity. We compared standard DAPT, DAPT with half-dose ticagrelor, and aspirin-free half-dose ticagrelor monotherapy initiated on the day of PCI in chronic coronary syndrome (CCS). Methods: Sixty-one East-Asian patients with CCS scheduled for elective PCI were randomized 1:1:1 to Control (aspirin plus clopidogrel), Experimental A (aspirin plus ticagrelor 45 mg twice daily), or Experimental B (ticagrelor 45 mg monotherapy, aspirin discontinued at day 2). DAPT arms continued for six months; Experimental B continued indefinitely. P2Y12 reaction units (PRU) were measured at baseline and at a median of 17 days. Results: PRU reduction was three-fold greater in both ticagrelor arms than in Control ({Delta}PRU -188 and -181 versus -60.5; P<0.001), with no difference between ticagrelor arms (P=0.772). At 12 months, major adverse cardiovascular events (MACE) and clinically relevant bleeding each occurred in 1 of 17 Experimental B patients (5.9%) and in neither other arm. One Experimental A patient crossed over for ticagrelor-induced dyspnea; no stent thrombosis or cardiac death occurred. Conclusions: In East-Asian patients with CCS, half-dose ticagrelor produced markedly greater platelet inhibition than standard DAPT, with an identical effect whether given with or without aspirin. It merits evaluation in an adequately powered randomized trial. Clinical Trial Registration. URL: https://www.clinicaltrials.gov; Unique Identifier: NCT07622056

Background: Cardiomyopathy and channelopathy (CC) gene variants have been linked to sudden cardiac arrest (SCA) or death (SCD) in small, selected pedigree or post-mortem studies of arrhythmic mitral valve prolapse (MVP). However, the utility of clinical whole exome sequencing (WES) panels as a risk stratification tool in unselected MVP samples is unknown. Objectives: The goal of the study was to test the utility of clinical WES panels with CC variant screening for arrhythmic risk stratification in MVP. Methods: We performed research based WES in 203 consecutive MVPs without other arrhythmic substrate. Variants were filtered for rare (<0.1%) and protein altering variants in 157 CC genes within an existing clinical panel and annotated with a clinical significance predictor. Overall frequency of CC variants was compared to a sample of general population exomes from gnomad v4.1.0. We assessed a composite severe arrhythmic outcome of SCD or frequent ectopy/ventricular tachycardia or ventricular fibrillation/SCA requiring catheter ablation or defibrillator implantation, respectively. Results: CC variants were more common in MVPs compared to the general population (RR: 4.3, p < 0.01). Pathogenic/Likely Pathogenic (P/LP) variants were identified in 18 MVPs (9%; 8 CC variants among 12 genes). P/LP variants were independently associated with the composite arrhythmic outcome after adjustment for traditional imaging parameters of risk including mitral annular disjunction and bileaflet involvement (OR: 1.23 [95% CI: 1.03 to 1.47], p = 0.01). P/LP variant carriers were at greater arrhythmic risk in time to event analyses starting at birth (HR: 2.87 [95% CI: 1.24 to 6.62], p = 0.01). Conclusions: A subset of MVPs with P/LP variants in CC genes are at higher arrhythmic risk. A clinical WES panel inclusive of CC variants may represent a valuable arrhythmic risk stratification tool in MVP beyond traditional imaging parameters.

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.

BACKGROUND Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive, life-threatening disease. Sociodemographic factors may influence time to treatment initiation and resulting clinical outcomes, yet these relationships are poorly characterized. OBJECTIVE Assess the effects of sex and race on tafamidis initiation and subsequent outcomes and their interaction with factors such as ATTR-CM type and social deprivation measures. METHODS A retrospective cohort analysis was conducted using the US Komodo Healthcare Map (01/2016-06/2024) among patients with amyloidosis, identified by ICD-10-CM diagnosis codes. Cumulative incidence of treatment initiation and survival probabilities for cardiovascular-related hospitalization (CVH) or death were estimated by Kaplan-Meier, stratified by sex and race. Cox proportional hazards models were fitted for both endpoints to estimate hazard ratios, adjusting for demographics and clinical characteristics. RESULTS Of 11,311 patients identified, White and Black patients (n=9,223) were included in subsequent analyses. Within 12 months of diagnosis, White women had the lowest cumulative incidence of tafamidis initiation (11.4%), followed by Black women (22.0%), Black men (26.7%), and White men (31.0%). Event-free survival at 12 months was lowest in Black women (42.9%), followed by Black men (46.8%), White women (48.6%), and White men (54.4%). Median (95% CI) time to CVH or death was shortest for Black women (8.0 months [6.8-10.0]) followed by Black men (9.9 months [8.8-12.0]), White women (11.0 months [9.6-13.0]), and White men (15.0 months [14.0-16.0]). CONCLUSIONS In this large, real-world cohort of US patients with ATTR-CM, sex and race contributed to disparities in tafamidis initiation and survival, underscoring compounded disparities in both access and outcomes.

Background: Bicuspid aortic valve anatomy increases procedural complexity during transcatheter aortic valve implantation, yet outcome-oriented anatomic risk stratification for intraprocedural events remains limited. Aims: We aimed to develop and externally validate an anatomy-driven score to predict a composite intraprocedural endpoint, assessed at exit from the procedure room, in bicuspid transcatheter aortic valve implantation. Methods: Consecutive patients with bicuspid aortic valve undergoing transcatheter aortic valve implantation were analysed in a development cohort (N=793) and a multicentre external validation cohort (N=134). Candidate preprocedural computed tomography and echocardiographic variables were prespecified by expert consensus and refined using penalized regression with bootstrap stability selection within a domain-constrained framework. A five-indicator score (0 to 10 points) was derived from routine imaging metrics spanning the ascending aorta, aortic root, valve complex, annulus-outflow tract unit, and left ventricle, and tested using multivariable logistic regression. Results: The composite intraprocedural endpoint occurred in 101/793 (12.7%) patients in the development cohort, with stepwise increases across risk strata (7.2%, 13.3%, 30.6%; p<0.001). Each 1-point increase was independently associated with higher risk (odds ratio 1.32; 95% confidence interval 1.18-1.47). A similar gradient was observed in external validation (3.1%, 10.8%, 50.0%; p=0.012; odds ratio 1.55 per point), with a C-statistic of 0.725. Higher risk categories were associated with lower early safety and higher 30-day and 1-year mortality. Conclusions: An anatomy-driven score derived from routine preprocedural imaging demonstrates graded discrimination of intraprocedural risk and may inform procedural planning in bicuspid transcatheter aortic valve implantation.

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 Structural heart disease (SHD) drives heart failure and cardiovascular mortality but remains underdiagnosed, and echocardiography is limited as a population-level screening tool. Objectives We evaluated whether a composite artificial intelligence-enabled electrocardiogram (AI-ECG), combining independently developed models for left ventricular systolic (LVSD) and diastolic dysfunction (LVDD), identifies prevalent and predicts incident SHD across diverse populations. Methods In this multinational cohort study, detection was assessed cross-sectionally in a Korean clinical cohort (Incheon Sejong Hospital) and a US dataset (Columbia University Irving Medical Center), and incident risk was assessed in the Korean cohort and the UK Biobank among individuals without baseline SHD or heart failure. Adults with paired ECG and echocardiography were analyzed for detection, with the composite defined as positive on either model. SHD comprised reduced left ventricular ejection fraction, moderate or severe valvular disease, left ventricular hypertrophy, or pulmonary hypertension. Detection was assessed by sensitivity and specificity, and incident risk by Cox models and the C statistic. Results Among 46,082 and 36,286 participants in the two detection cohorts, the composite detected SHD with sensitivity of 71.8% and 76.1% and specificity of 88.3% and 70.1%, with positivity across all phenotypes. Among at-risk individuals, composite positivity was associated with incident SHD (hazard ratios, 3.75 and 2.75), with C statistics of 0.69 to 0.78. Conclusions A composite AI-ECG identified prevalent and predicted incident SHD across multinational cohorts, capturing signals beyond its training targets and supporting its potential as a scalable cardiovascular screening tool; whether ECG-based risk stratification improves outcomes requires prospective evaluation.

Arrhythmia risk rises early in many forms of cardiac stress, often before contractile failure is evident. Stressed cardiomyocytes accumulate biomolecular condensates, known as stress granules (SGs), whose contribution to this electrical vulnerability has been unclear. We mapped where SGs reside and followed their life cycle under acute and chronic oxidative stress across complementary model systems and assessed electrophysiological consequences with pharmacological tools targeting granule assembly, microtubule integrity, and calcium channel function. Under both stress regimes, SGs localized preferentially to z-lines and intercalated discs, marking these mechanically critical sites as hubs of condensate assembly. Merging of granules, referred to as coarsening, rather than initial formation, emerged as a pathological connection. Early granules were broadly cytoprotective, whereas progressive coarsening was accompanied by disruption of alpha-actinin and L-type calcium channel (Cav1.2) nanodomains and by shortening of action potential (AP) duration. Coarsened granules disorganized Cav1.2 nanodomains through a microtubule-dependent mechanism, and arresting coarsening with nocodazole preserved nanodomain integrity and restored AP morphology. The transition from nascent to coarsened SGs therefore represents a targetable inflection point, and limiting coarsening may prevent proarrhythmic remodeling during cardiac oxidative stress.

Background: Finerenone, a non-steroidal mineralocorticoid receptor antagonist (nsMRA), improves cardiorenal outcomes in chronic kidney disease, type 2 diabetes, and heart failure. However, its clinical efficacy and safety when initiated early after acute myocardial infarction (AMI) remain unknown. Methods: This retrospective cohort study utilized the TriNetX global federated network to identify adult patients with AMI who initiated finerenone within 6 months of the index event. These were compared to a propensity score-matched control group of AMI survivors who did not receive finerenone. Results: After 1:1 propensity score matching, 1,012 patients were included (506 per group; mean age 69 years). The cohort represented a high-risk phenotype with a high prevalence of type 2 diabetes (~84%) and CKD (~80%). Over a 2-year follow-up, finerenone treatment was associated with a lower risk of the composite endpoint of mortality and heart failure (HR 0.644; 95% CI 0.495?0.837; P < 0.001). Notably, finerenone was also associated with a lower risk of progression to ESRD or CKD stage 5 (HR 0.573; 95% CI 0.387?0.851; P = 0.005) and all-cause hospitalization (HR 0.602; 95% CI 0.482?0.751; P < 0.001). There was no significant difference in the risk of adverse events, including hyperkalemia, hyponatremia, and syncope or hypotension between groups. Conclusion: In this real-world study of high-risk post-AMI patients, early initiation of finerenone was associated with lower risks of composite cardiovascular events, all-cause mortality, and renal disease progression, without a significant increase in adverse events. These findings warrant validation in prospective randomized controlled trials.

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.

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: Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome comprising multiple pathophysiological phenotypes. HFpEF trials have largely enrolled diverse populations and reported average treatment effects, consistently yielding neutral results that may obscure drug-specific benefits within distinct subgroups. To address this issue, we employ an interaction-based that incorporates treatment-by-variable interactions to uncover drug-specific responses. Methods: We leveraged four HFpEF clinical trials (TOPCAT, RELAX, NEAT-HFpEF, INDIE-HFpEF) and developed a framework comprising two complementary approaches. The first employed a prognostic responder model to evaluate whether conventional responder definitions reflect treatment-specific benefit or instead capture favorable clinical trajectories common to both treatment and placebo groups. The second used an interaction-based individual treatment effect (ITE) modeling to identify baseline variables that modify therapy effect, distinguishing drug-specific response from prognostic phenotypes. Results: Although the prognostic responder model demonstrated good discrimination, further analisys suggested it primarily captured a prognostic signal associated with favorable clinical trajectories common to both treatment and placebo arms. In contrast, the ITE model identified distinct, drug-specific effect modifiers across trials (cardiorenal-inflammatory for spironolactone (TOPCAT), NO-mediated anti-inflammatory for isosorbide mononitrate (NEAT-HFpEF), afterload-reducing for inorganic nitrite (INDIE-HFpEF), and anti-volume-overload for sildenafil (RELAX). Each ITE model demonstrated significance only within its own trial suggesting drug-specific signal. Conclusions: The proposed method identifies mechanism-specific effect modifiers, and uncovers clinically meaningful heterogeneity in treatment response, which is not captured by conventional MCID-based approaches. Although exploratory, these findings support phenotype-guided therapy in HFpEF and argue for phenotype-informed trial design to enhance treatment-effect detection and therapy targeting.

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.

Background: Suspected acute coronary syndrome is a frequent Emergency Department (ED) presentation, requiring safe and efficient assessment. We interrogated long-term trends in whole population care for these patients using a new multi-centre regional registry. Methods: The DataLoch Heart Disease Registry links relevant data from primary and secondary healthcare records, with national administrative data for patients registered within the Lothian Health Board region of Scotland (~1M population). We included all adult patients presenting to secondary- or tertiary-care EDs in the region between 2014 and 2024, in whom high-sensitivity cardiac troponin was measured within 24 hours of presentation. Annual diagnostic rates for myocardial infarction, pharmacological and interventional management, and outcomes up to 1 year after ED presentation were studied. Logistic regression models were used to report change in annual trends for myocardial infarction, cardiac death, cardiovascular death and all-cause mortality, adjusted for age, sex, ethnicity, socioeconomic deprivation and comorbidity. Results: Over 10 years, 117,142 consecutive patients (mean age 58 +/- 18 years, 48% female, 6.6% with confirmed myocardial infarction) were included. Cardiac troponin testing increased year on year, from 61 per 1000 ED attendances in 2014 to 103 per 1000 in 2024 (P<0.001), but the proportion of patients admitted to hospital fell (59% in 2014 to 38% in 2024, P<0.001). Associated with these trends, the tested population had fewer cardiovascular risk factors and myocardial infarction incidence fell from 73 per 1000 tested patients in 2014 to 47 per 1000 in 2024 (adjusted odds ratio 0.62, 95% confidence intervals 0.56 to 0.69, P<0.001). In patients diagnosed with myocardial infarction, prescriptions of preventative therapies and numbers of revascularisation procedures were unchanged. After adjustment, no change over time was observed in one-year cardiac or cardiovascular mortality in those with a diagnosis of myocardial infarction. Conclusions: ED testing using cardiac troponin has extended to a broader population at lower risk of myocardial infarction. Despite this trend, early rule-out pathways have reduced hospital admissions, without observable changes in outcomes for those with myocardial infarction.