Circulation: Heart Failure最新文献

Background: In patients with right ventricular (RV) outflow tract stenosis and pulmonary regurgitation (PR), percutaneous pulmonary valve implantation (PPVI) aims to preserve RV and left ventricular (LV) integrity and function. Our study aimed to assess acute changes in biventricular intrinsic myocardial function occurring with PPVI.

Methods: Twenty patients with RV outflow tract dysfunction (mean±1 SD; age, 23.0±10.9 years; mean peak echocardiographic RV outflow tract gradient, 64±25 mm Hg) underwent PPVI with biventricular assessment of pressure-volume loops using the conductance catheter technique during the same cardiac catheterization. Load-independent parameters of ventricular contractility (ventricular elastance) and ventricular compliance function, as well as pulmonary/systemic arterial elastance and ventriculoarterial coupling, were assessed before and directly after PPVI. Cardiac magnetic resonance for quantification of biventricular volumes, function, and PR was also performed.

Results: After PPVI, both RV ventricular elastance (median [interquartile range], 0.26 [0.16-0.83] to 0.19 [0.13-0.42] mm Hg/mL per m²; P=0.029) and pulmonary systemic arterial elastance (0.32±0.20 to 0.25±0.19 mm Hg/mL per m²; P<0.001) decreased significantly, while right ventriculoarterial coupling (1.14±0.61 to 1.10±0.59; P=0.76) did not change statistically significant. LV ventricular elastance (1.31±0.93 to 1.23±0.72 mm Hg/mL per m²; P=0.68) and left ventriculoarterial coupling (0.75 [0.51-1.23] to 0.82 [0.53-1.10]; P=0.98) were not affected by PPVI although systemic arterial elastance increased significantly (0.83±0.26 to 0.90±0.34 mm Hg/mL per m²; P=0.032). Both RV (P=0.37) and LV (P=0.20) compliance showed no significant change after PPVI. Patients with relevant PR (≥25%; n=10) had lower RV ventricular elastance (P=0.043) before and higher LV compliance (P=0.010) after PPVI compared with patients with minor PR (<25%; n=10), whereas ventriculoarterial coupling was similar between the 2 groups.

Conclusions: Acute reduction of RV overload by PPVI is accompanied by an instantaneous decline in RV contractility with persistent and inefficient ventriculoarterial coupling. The LV adequately adapts to an increase in pre- and post-load with nonsignificant changes in LV intrinsic function and ventriculoarterial coupling. The relevance of these response patterns on long-term biventricular remodeling requires further investigation.

Background: Transthyretin amyloid cardiomyopathy (ATTR-CM) causes a restrictive cardiomyopathy resulting in heart failure (HF). Signaling pathways associated with ATTR-CM are not well defined. The purpose of this study was to identify signaling pathways that are dysregulated in ATTR-CM compared with controls.

Methods: This was a case-control study of cases with ATTR-CM, internal controls with hypertensive left ventricular hypertrophy, and external controls with HF. For model development, ATTR-CM cases were age- and sex-matched with internal controls with hypertensive left ventricular hypertrophy. Plasma proteomics profiling of 7289 proteins was conducted. A sparse partial least squares discriminant analysis was performed to develop a proteomics-based discrimination model from 70% of the data (ie, the training set), and the discriminative ability was tested in the remaining 30% of the data (ie, the internal test set). External validation using HF controls was also conducted. Pathway analysis of significantly (ie, univariable P<10^-6) dysregulated proteins was executed. Signaling pathways with a false discovery rate <0.05 were declared positive.

Results: The analysis included 169 cases and 220 controls. A total of 211 discriminant proteins were identified in the training set from the proteomics-based model developed to distinguish ATTR-CM cases from 170 internal controls with hypertensive left ventricular hypertrophy. The area under the receiver-operating characteristic curve to discriminate ATTR-CM in the test set from 50 external controls with HF was 0.89 (95% CI, 0.82-0.96). The sensitivity was 0.90 (95% CI, 0.75-0.97), and the specificity was 0.86 (95% CI, 0.72-0.96). Pathway analysis revealed the PI3K-Akt (phosphoinositide-3-kinase-protein kinase) pathway and its related pathways (eg, JAK-STAT [Janus kinase-signal transducer and activator of transcription]) were dysregulated. Dysregulation of previously identified pathways, such as the complement and coagulation cascade pathways, was also observed.

Conclusions: This study reveals a distinct proteomic profile of ATTR-CM compared with controls with HF, and elucidates both novel and known signaling pathways that are differentially regulated in ATTR-CM.

Background: Less than 1 in 3 patients in the United States with heart failure (HF) with reduced ejection fraction are receiving guideline-recommended medical therapy. Remote titration programs outside of structured episodes of care may address this issue and improve the implementation of guideline-recommended care.

Methods: AIM-POWER (Artificial Intelligence Mobile Health Trial of a Digital Platform to Optimize Guideline-Directed Heart Failure Therapy Using Wearable Sensors) was a multicenter, open-label, clinical trial of participants with HF with reduced ejection fraction who were not optimized on medical therapy designed to evaluate the safety and efficacy of a digital intervention to guide optimal initiation and titration of pharmacological therapy. Participants were randomized 1:1 to a BiovitalsHF intervention or usual care and followed for 90 days. Participants receiving the intervention assessed their weight daily, and blood pressure and heart rate twice daily. These data were collected remotely and used to create outpatient medication titration recommendations from the BiovitalsHF platform to site clinicians every 2 weeks. The primary outcome was the between-group difference in the change in an HF optimal therapy score.

Results: We randomized 122 participants at 21 sites in the United States. The mean (±SD) age of the participants was 61.6±12.4 years, and 69% were male. The mean left ventricular ejection fraction was 29±6.7%, and the mean baseline HF optimal therapy score was 3.8±1.8 (range, 0-8). At 90 days after randomization, the change in the score was significantly greater in the intervention group than usual care group (1.72 ±1.75 intervention versus 0.44 ±1.18 usual care; P<0.001).

Conclusions: In participants with HF with reduced ejection fraction who were not yet optimized on medical therapy, a digital intervention that focused on the optimization of HF pharmacological therapy resulted in a significantly greater change in an HF optimal therapy score at 90 days than usual care.

Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04191330.

Background: Hypertrophic cardiomyopathy (HCM) is an important cause of morbidity and mortality in children, but treatment options are limited. Aficamten, a next-in-class cardiac myosin inhibitor, directly targets the hypercontractility underlying HCM. Aficamten improved exercise capacity, health status, and symptoms in adults with obstructive HCM in the pivotal, phase 3 SEQUOIA-HCM trial (Safety, Efficacy, and Quantitative Understanding of Obstruction Impact of Aficamten in HCM; NCT05186818).

Methods: CEDAR-HCM (Clinical Evaluation of dosing With Aficamten to Reduce Obstruction in Pediatric Population With HCM) is an international, multicenter, randomized, double-blind, placebo-controlled trial followed by an open-label extension to evaluate the efficacy, safety, and pharmacokinetics of aficamten in pediatric participants with symptomatic obstructive HCM. The trial will enroll ≈55 adolescents (12 to <18 years) and subsequently expand to include at least 10 children (6 to <12 years) with nonsyndromic obstructive HCM, left ventricular ejection fraction ≥60%, Valsalva left ventricular outflow tract gradient ≥50 mm Hg, and New York Heart Association functional class ≥II. Participants will be randomized 2:1 to aficamten or placebo in addition to standard of care therapy or as monotherapy, with echocardiogram-guided dose adjustments targeting a Valsalva left ventricular outflow tract gradient <30 mm Hg while maintaining left ventricular ejection fraction ≥50%. The primary end point is the change in Valsalva left ventricular outflow tract gradient from baseline to week 12. Secondary end points include change in resting left ventricular outflow tract gradient, cardiac biomarkers, New York Heart Association functional class, and assessment of pharmacokinetics. After completing the 12-week randomized period, eligible participants will continue into a long-term open-label extension.

Results: The trial is currently enrolling.

Conclusions: Results of CEDAR-HCM will provide insight into the safety and efficacy of aficamten in adolescents and in children as young as 6 years of age.

Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT06412666.

Background: MGP (matrix Gla-protein), a known inhibitor of vascular calcification, becomes biologically active by vitamin K-dependent carboxylation. Circulating levels of dpucMGP (dephospho-uncarboxylated matrix Gla-protein), the inactive form of MGP, have been associated with large artery stiffening and reduced skeletal muscle mass in heart failure (HF). Whether dpucMGP is related to adverse outcomes in patients with HF is unknown.

Methods: In this cohort study, we measured plasma dpucMGP among 2247 PHFS (Penn HF Study) participants. We examined the relationship between dpucMGP and ≈5000 other proteins (SomaScan assay) to identify biological pathways associated with dpucMGP. We assessed the association between dpucMGP levels and (1) death or HF-related hospital admission; (2) all-cause death.

Results: Participants' median age was 61 years (interquartile range, 53-70 years), 64% were male, and 71% were White. dpucMGP exhibited prominent proteomic associations with acute phase response, coagulation, complement system, fibrosis, cell signaling, and metabolic pathways. Greater dpucMGP was associated with older age, renal dysfunction, and warfarin use, whereas Black ethnicity was associated with lower dpucMGP. Increased dpucMGP levels were associated with an increased risk of death or HF-related hospital admission (standardized hazard ratio, 1.23 [95% CI, 1.17-1.28]; P<0.0001) and all-cause death (standardized hazard ratio, 1.32 [95% CI, 1.25-1.40]; P<0.0001), particularly among participants with nonischemic HF. Associations between dpucMGP and outcomes were dependent on warfarin use, and higher dpucMGP levels were found to mediate the association between warfarin use and adverse outcomes (death [total effect: P=0.005; indirect effect: P<0.001] and death or HF-related hospital admission [total effect: P<0.001; indirect effect: P=0.002]).

Conclusions: Higher dpucMGP is associated with multiple biological pathways and with an increased risk for adverse outcomes in HF. Greater dpucMGP levels mediated the relationship between warfarin use and adverse outcomes. Further studies are required to determine the role of therapeutic interventions to reduce dpucMGP levels in this patient population.

Background: Arrhythmogenic cardiomyopathy (ACM) is a fatal genetic heart disease primarily caused by mutations in desmosomal genes, leading to impaired cell-cell adhesion, ventricular arrhythmias, and progressive heart failure. Although gene therapy for specific ACM populations shows promise, it remains unclear whether mutation-agnostic pathways dysregulated across desmosomal mutations could be exploited for therapeutic intervention in this genetically broad and severe population. The reduction in expression of the ventricular gap junction protein Cx43 (connexin-43) is a common molecular alteration underlying desmosomal junctional deficits and arrhythmias, suggesting a potential common underlying mechanism and a therapeutic target for ACM. We hypothesized that restoration of Cx43 expression could be a mutation-agnostic intervention for ACM.

Methods: We exploited adeno-associated-viral-mediated gene therapy to restore the gap junction protein, Cx43, in genetic mouse models and human stem cell models of ACM, harboring loss or mutations in desmosomal genes, including desmoplakin (Dsp), plakophilin-2 (PKP2), and desmoglein-2 (DSG2).

Results: Administration of AAV-Cx43 (adeno-associated-viral-mediated connexin-43) gene therapy alleviated the severe biventricular dilatation, contractile dysfunction, and arrhythmias, while prolonging lifespan in 2 severe desmosomal ACM mouse models, either harboring Dsp loss and a prevalent human PKP2 mutation. Viral-mediated restoration of Cx43 could also alleviate physiological deficits in ACM human induced pluripotent stem cell-derived cardiomyocytes harboring PKP2 and DSG2 mutations. Mechanistically, Cx43 targets desmosomal protein expression and relocalization to the cell junction to support their mechanical stabilization and coupling.

Conclusions: By using mouse and human models of desmosomal ACM harboring different mutational backgrounds, we show the sufficiency of Cx43 gene therapy and its restoration to modify and alleviate ACM deficits. These data suggest that noncanonical functions of Cx43, including mechanical modulation and reassembly of the desmosome, are a therapeutic target with the potential to treat diverse ACM populations.