Effects of Serelaxin in Patients with Acute Heart Failure

Therapeutic potential of relaxin or relaxin mimetics in managing cardiovascular complications of diabetes

Diabetes mellitus is a metabolic disease with an escalating global prevalence. Despite the abundance and relative efficacies of current therapeutic approaches, they primarily focus on attaining the intended glycaemic targets, but patients ultimately still suffer from various diabetes-associated complications such as retinopathy, nephropathy, cardiomyopathy, and atherosclerosis. There is a need to explore innovative and effective diabetic treatment strategies that not only address the condition itself but also combat its complications. One promising option is the reproductive hormone relaxin, an endogenous ligand of the RXFP1 receptor. Relaxin is known to exert beneficial actions on the cardiovascular system through its vasoprotective, anti-inflammatory and anti-fibrotic effects. Nevertheless, the native relaxin peptide exhibits a short biological half-life, limiting its therapeutic potential. Recently, several relaxin mimetics and innovative delivery technologies have been developed to extend its biological half-life and efficacy. The current review provides a comprehensive landscape of the cardiovascular effects of relaxin, focusing on its potential therapeutic applications in managing complications associated with diabetes. The latest advancements in the development of relaxin mimetics and delivery methods for the treatment of cardiometabolic disorders are also discussed.

The utility of urine sodium-guided diuresis during acute decompensated heart failure

Diuresis to achieve decongestion is a central aim of therapy in patients hospitalized for acute decompensated heart failure (ADHF). While multiple approaches have been tried to achieve adequate decongestion rapidly while minimizing adverse effects, no single diuretic strategy has shown superiority, and there is a paucity of data and guidelines to utilize in making these decisions. Observational cohort studies have shown associations between urine sodium excretion and outcomes after hospitalization for ADHF. Urine chemistries (urine sodium ± urine creatinine) may guide diuretic titration during ADHF, and multiple randomized clinical trials have been designed to compare a strategy of urine chemistry-guided diuresis to usual care. This review will summarize current literature for diuretic monitoring and titration strategies, outline evidence gaps, and describe the recently completed and ongoing clinical trials to address these gaps in patients with ADHF with a particular focus on the utility of urine sodium-guided strategies.

Research progress of knee fibrosis after anterior cruciate ligament reconstruction

Anterior cruciate ligament (ACL) injury is a common sports injury, and ACL reconstruction is an effective surgery for this trauma. Most cases gain good recovery after surgery, while some patients may experience knee stiffness, which is characterized by joint fibrosis, leading to reduced joint mobility, pain, and dysfunction. Currently, various research studies have been conducted to unveil the mechanisms underlying this condition, identifying pre-, intra-, and post-operative risk factors, and testify the efficacy of different therapeutic methods against it. In this review, we summarize the current progress regarding the advancements in knee fibrosis after ACL reconstruction. The risk factors associated with knee fibrosis are systematically delineated, accompanied by an evaluation of the efficacy of various treatment modalities for both the prevention and mitigation of fibrosis. Furthermore, recommendations for future research directions are proposed, offering a foundational basis for subsequent investigations.

Prognostic association of circulating relaxin-2 in acute heart failure

BACKGROUND

Despite the increasing interest in the study of the endogenous relaxin system in heart failure (HF), its role as a prognostic marker in acute HF remains unclear. We aimed to evaluate the association of relaxin-2 circulating levels with 6 months' mortality in acute HF.

METHODS

We evaluated relaxin-2 serum levels at admission in a cohort of patients with acute HF (n = 202) using an enzyme immunoassay. The ability of relaxin-2 to predict all-cause death (primary outcome) and HF-specific death (secondary outcome) at 6 months was assessed using Cox-regression analysis.

RESULTS

The median age was 79 (70-85) years old, 44% of the patients were male, and 43% had preserved ejection fraction (≥50%). Median serum relaxin-2 level was 25 pg/mL. Patients with higher relaxin-2 levels had more peripheral oedemas, higher sodium retention score, higher pulmonary artery pressures, higher prevalence of right ventricle dysfunction and lower inferior vena cava collapse at inspiration. Conversely, there was no association with left chambers parameters or with B-type natriuretic peptide (BNP). Higher relaxin-2 concentrations were associated with a higher risk of all-cause death [HR 1.15; 95%CI 1.01,1.30; P = 0.030] and HF-specific death [HR 1.21; 95% CI 1.03-1.42; P = 0.018], after adjustment for classical prognostic factors such as age, sex and BNP.

CONCLUSIONS

In our acute HF population, relaxin-2 circulating levels were associated with clinical and echocardiographic markers of systemic congestion and with 6-months' mortality, independently of BNP. These results lay the groundwork for future investigations on the potential of relaxin-2 as an auxiliary biomarker in HF.

Distinct Comorbidity Clusters in Patients With Acute Heart Failure: Data From RELAX-AHF-2

BACKGROUND

Multimorbidity frequently occurs in patients with acute heart failure (AHF). The co-occurrence of comorbidities often follows specific patterns.

OBJECTIVES

This study investigated multimorbidity subtypes and their associations with clinical outcomes.

METHODS

From the prospective RELAX-AHF-2 (Relaxin for the Treatment of Acute Heart Failure-2) trial, 6,545 patients (26% with HF with preserved ejection fraction, defined as LVEF ≥50%) were classified into multimorbidity groups using latent class analysis. The association between subgroups and clinical outcomes was examined. Validation of these findings was conducted in the RELAX-AHF trial, which comprised 1,161 patients.

RESULTS

Five distinct multimorbidity groups emerged: 1) diabetes and chronic kidney disease (CKD) (often male, high prevalence of CKD and diabetes mellitus); 2) ischemic (ischemic HF); 3) elderly/atrial fibrillation (AF) (oldest, high prevalence of AF); 4) metabolic (obese, hypertensive, more often HF with preserved ejection fraction); and 5) young (fewest comorbidities). After adjusting for confounders, patients in the diabetes and CKD (HR: 1.80; 95% CI: 1.50-2.20), elderly/AF (HR: 1.42; 95% CI: 1.20-1.70), and metabolic (HR: 1.40; 95% CI: 1.20-1.80) groups had higher rates of the composite outcome than patients in the young group, primarily driven by differences in rehospitalization. Treatment allocation (placebo or serelaxin) modified these associations (Pinteraction <0.001). Serelaxin-treated patients in the young group were associated with a lower risk for all-cause mortality (HR: 0.59; 95% CI: 0.40-0.90). Similarly, patients from the RELAX-AHF trial clustered in 5 multimorbidity groups. The clinical characteristics and associations with outcomes could also be validated.

CONCLUSIONS

Comorbidities naturally clustered into 5 mutually exclusive groups in RELAX-AHF-2, showing variations in clinical outcomes. These data emphasize that the specific combination of comorbidities can influence adverse outcomes and treatment responses in patients with AHF.

Impact of age on clinical outcomes and response to serelaxin in patients with acute heart failure: An analysis from the RELAX-AHF-2 trial

AIMS

Acute heart failure (AHF) is a major cause of hospitalizations and death in the elderly. However, elderly patients are often underrepresented in randomized clinical trials. We analysed the impact of age on clinical outcomes and response to treatment in patients enrolled in Relaxin in Acute Heart Failure (RELAX-AHF-2), a study that included older patients than in previous AHF trials.

METHODS AND RESULTS

The RELAX-AHF-2 randomized patients admitted for AHF to infusion of serelaxin or placebo. We examined the association of pre-specified clinical outcomes and treatment effect according to age categories [(years): <65 (n = 1411), 65-74 (n = 1832), 75-79 (n = 1222), 80-84 (n = 1156) and ≥85 (n = 924)]. The mean age of the 6545 patients enrolled in RELAX-AHF-2 was 73.0 ± 11 years. The risk of all-cause and cardiovascular (CV) death (all p < 0.001) as well as the composite endpoint of CV death or heart failure/renal failure rehospitalization through 180 days (p = 0.002) and hospital discharge through day 60 (p = 0.013) were all directly associated with age categories. Age remained independently associated with outcomes after adjustment for clinical confounders and the results were consistent when age was analysed continuously. No clinically significant change in treatment effects of serelaxin was observed across age categories for the pre-specified endpoints (interaction p > 0.05).

CONCLUSION

Elderly patients are at higher risk of short- and long-term CV outcomes after a hospitalization for AHF. Further efforts are needed to improve CV outcomes in this population.

Engineering and Characterization of a Long-Half-Life Relaxin Receptor RXFP1 Agonist

Relaxin-2 is a peptide hormone with important roles in human cardiovascular and reproductive biology. Its ability to activate cellular responses such as vasodilation, angiogenesis, and anti-inflammatory and antifibrotic effects has led to significant interest in using relaxin-2 as a therapeutic for heart failure and several fibrotic conditions. However, recombinant relaxin-2 has a very short serum half-life, limiting its clinical applications. Here, we present protein engineering efforts targeting the relaxin-2 hormone in order to increase its serum half-life while maintaining its ability to activate the G protein-coupled receptor RXFP1. To achieve this, we optimized a fusion between relaxin-2 and an antibody Fc fragment, generating a version of the hormone with a circulating half-life of around 3 to 5 days in mice while retaining potent agonist activity at the RXFP1 receptor both in vitro and in vivo.

Relaxin suppresses atrial fibrillation, reverses fibrosis and reduces inflammation in aged hearts

Healthy aging results in cardiac structural and electrical remodeling that increase susceptibility to cardiovascular diseases. Relaxin has shown broad cardioprotective effects including anti-fibrotic, anti-arrhythmic and anti-inflammatory outcomes in multiple models. This paper focuses on the cardioprotective effects of Relaxin in a rat model of aging. Sustained atrial or ventricular fibrillation are readily induced in the hearts of aged but not young control animals. Treatment with Relaxin suppressed this arrhythmogenic response by increasing conduction velocity, decreasing fibrosis and promoting substantial cardiac remodeling. Relaxin treatment resulted in a significant increase in the levels of: Nav1.5, Cx43, βcatenin and Wnt1 in rat hearts. In isolated cardiomyocytes, Relaxin increased Nav1.5 expression. These effects were mimicked by CHIR 99021, a pharmacological activator of canonical Wnt signaling, but blocked by the canonical Wnt inhibitor Dickkopf1. Relaxin prevented TGF-β-dependent differentiation of cardiac fibroblasts into myofibroblasts while increasing the expression of Wnt1; the effects of Relaxin on cardiac fibroblast differentiation were blocked by Dickkopf1. RNASeq studies demonstrated reduced expression of pro-inflammatory cytokines and an increase in the expression of α- and β-globin in Relaxin-treated aged males. Relaxin reduces arrhythmogenicity in the hearts of aged rats by reduction of fibrosis and increased conduction velocity. These changes are accompanied by substantial remodeling of the cardiac tissue and appear to be mediated by increased canonical Wnt signaling. Relaxin also exerts significant anti-inflammatory and anti-oxidant effects in the hearts of aged rodents. The mechanisms by which Relaxin increases the expression of Wnt ligands, promotes Wnt signaling and reprograms gene expression remain to be determined.

Engineering a long acting, non-biased relaxin agonist using Protein-in-Protein technology

The peptide hormone relaxin plays a critical role in tissue remodeling in a variety of tissues through activation of its cognate receptor, RXFP1. Relaxin's ability to modify extracellular matrices has provided a strong rationale for treating fibrosis in a variety of tissues. Treatment with recombinant relaxin peptides in clinical studies of heart failure has not yet proven useful, likely due to the short half-life of infused peptide. To circumvent this particular pharmacokinetic pitfall we have used a Protein-in-Protein (PiP) antibody technology described previously, to insert a single-chain human relaxin construct into the complementarity-determining region (CDR) of an immunoglobulin G (IgG) backbone, creating a relaxin molecule with a half-life of ∼4-5 days in mice. Relaxin-PiP biologics displaced Europium-labeled human relaxin in RXFP1-expressing cells and demonstrated full agonist activity on both human and mouse RXFP1 receptors. Relaxin-PiPs did not show signal transduction bias, as they activated cAMP in THP-1 cells, and cGMP and pERK signaling in primary human cardiac fibroblasts. In an induced carbon tetrachloride mouse model of liver fibrosis one relaxin-PiP, R2-PiP, caused reduction of liver lesions, ameliorated collagen accumulation in the liver with the corresponding reduction of Collagen1a1 gene expression, and increased cell proliferation in hepatic parenchyma. These relaxin biologics represent a novel approach to the design of a long-acting RXFP1 agonist to probe the clinical utility of relaxin/RXFP1 signaling to treat a variety of human fibrotic diseases.

Novel Relaxin Receptor RXFP1 Agonist AZD3427 in the Treatment of Heart Failure: A Phase 1a/b, First-in-Human, Randomized, Single-Blind, Placebo-Controlled Study

BACKGROUND

Heart failure mortality remains high despite recent progress in pharmacological treatment. AZD3427 is a selective long-acting analog of relaxin, a vasodilatory hormone with antifibrotic effects. We assessed the safety, pharmacokinetics, and pharmacodynamics of AZD3427 in healthy volunteers and patients with heart failure on standard-of-care therapy.

METHODS AND RESULTS

In this first-in-human, phase 1a/b, randomized, single-blind, placebo-controlled study, healthy volunteers were randomized 6:2 to receive a single dose of AZD3427 or placebo by subcutaneous injection in 5 mixed-ethnicity cohorts (5, 10, 30, 90, or 270 mg) and 1 Japanese-descent cohort (270 mg), or by intravenous injection in 1 cohort (15 mg). After confirming safety and tolerability in healthy volunteers, 3 cohorts of patients with heart failure and left ventricular ejection fraction ≤40% and 3 cohorts with ejection fraction ≥41% were randomized 6:2 to receive 5 weekly doses of AZD3427 (5, 15, or 45 mg) or placebo by subcutaneous injection. In total, 56 healthy volunteers and 48 patients with heart failure were randomized. AZD3427 was well tolerated at all doses. After subcutaneous administration, AZD3427 was absorbed slowly, and exposure was approximately linear across the dose range. In patients with heart failure, AZD3427 terminal half-life was 13 to 14 days and there were numerical increases in stroke volume and estimated glomerular filtration rate. No treatment-emergent antidrug antibodies were detected.

CONCLUSIONS

AZD3427 had favorable safety and pharmacokinetic profiles. Hemodynamic changes in patients with heart failure were consistent with the anticipated effects of a relaxin analog. These findings support further development of AZD3427 as a novel long-term treatment for patients with heart failure.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique Identifier: NCT04630067.

Prediction of cardiac worsening through to cardiogenic shock in patients with acute heart failure

AIMS

Acute heart failure (AHF) can result in worsening of heart failure (WHF), cardiogenic shock (CS), or death. Risk factors for these adverse outcomes are not well characterized. This study aimed to identify predictors for WHF or new-onset CS in patients hospitalized for AHF.

METHODS AND RESULTS

Prospective cohort study enrolling consecutive patients with AHF admitted to a large tertiary care centre with follow-up until death or discharge. WHF was defined by the RELAX-AHF-2 criteria. CS was defined as SCAI stages B-E. Potential predictors were assessed by fitting logistic regression models adjusted for age and sex. N = 233 patients were enrolled, median age was 78 years, and 80 were women (35.9%). Ischaemic cardiomyopathy was present in 82 patients (40.8%). Overall, 96 (44.2%) developed WHF and 18 (9.7%) CS. In-hospital death (8/223, 3.6%) was related to both events (WHF: OR 6.64, 95% CI 1.21-36.55, P = 0.03; CS: OR 38.27, 95% CI 6.32-231.81, P < 0.001). Chronic kidney disease (OR 2.20, 95% CI 1.25-3.93, P = 0.007), logarithmized serum creatinine (OR 2.90, 95% CI 1.51-5.82, P = 0.002), cystatin c (OR 1.86, 95% CI 1.27-2.77, P = 0.002), tricuspid valve regurgitation (OR 2.08, 95% CI 1.11-3.94, P = 0.023) and logarithmized pro-adrenomedullin (OR 3.01, 95% CI 1.75-5.38, P < 0.001) were significant predictors of WHF. Chronic kidney disease (OR 3.17, 95% CI 1.16-9.58, P = 0.03), cystatin c (OR 1.88, 95% CI 1.00-3.53, P = 0.045), logarithmized pro-adrenomedullin (OR 2.90, 95% CI 1.19-7.19, P = 0.019), and tricuspid valve regurgitation (OR 10.44, 95% CI 2.61-70.00, P = 0.003) were significantly with new-onset CS.

CONCLUSIONS

Half of patients admitted with AHF experience WHF or new-onset CS. Chronic kidney disease, tricuspid valve regurgitation, and elevated pro-adrenomedullin concentrations predict these events. They could potentially serve as early warning signs for further deterioration in AHF patients.

Cardiovascular effects of relaxin-2: therapeutic potential and future perspectives

The hormone relaxin-2 has emerged as a promising player in regulating the physiology of the cardiovascular system. Through binding to the relaxin family peptide receptor 1 (RXFP1), this hormone elicits multiple physiological responses including vasodilation induction, reduction of inflammation and oxidative stress, and angiogenesis stimulation. The role of relaxin-2, or its recombinant human form known as serelaxin, has been investigated in preclinical and clinical studies as a potential therapy for cardiovascular diseases, especially heart failure, whose current therapy is still unoptimized. However, evidence from past clinical trials has been inconsistent and further research is needed to fully understand the potential applications of relaxin-2. This review provides an overview of serelaxin use in clinical trials and discusses future directions in the development of relaxin-2 mimetics, which may offer new therapeutic options for patients with heart failure.

Translational pharmacokinetic/pharmacodynamic model for mRNA-0184, an investigational therapeutic for the treatment of heart failure

Heart failure (HF) is a complex, progressive disorder that is associated with substantial morbidity and mortality on a global scale. Relaxin-2 is a naturally occurring hormone that may have potential therapeutic benefit for patients with HF. To investigate the therapeutic potential of relaxin in the treatment of patients with HF, mRNA-0184, a novel, investigational, lipid nanoparticle (LNP)-encapsulated mRNA therapy that encodes for human relaxin-2 fused to variable light chain kappa (Rel2-vlk) was developed. A translational semi-mechanistic population pharmacokinetic (PK)/pharmacodynamic (PD) model was developed using data from non-human primates at dose levels ranging from 0.15 to 1 mg/kg. The PK/PD model was able to describe the PK of Rel2-vlk mRNA and translated Rel2-vlk protein in non-human primates adequately with relatively precise estimates. The preclinical PK/PD model was then scaled allometrically to determine the human mRNA-0184 dose that would achieve therapeutic levels of Rel2-vlk protein expression in patients with stable HF with reduced ejection fraction. Model-based simulations derived from the scaled PK/PD model support the selection of 0.025 mg/kg as an appropriate starting human dose of mRNA-0184 to achieve average trough relaxin levels between 1 and 2.5 ng/mL, which is the potential exposure for cardioprotective action of relaxin.

The art of healing hearts: Mastering advanced RNA therapeutic techniques to shape the evolution of cardiovascular medicine in biomedical science

Cardiovascular diseases (CVDs) are the leading cause of death worldwide and are associated with increasing financial health burden that requires research into novel therapeutic approaches. Since the early 2000s, the availability of next-generation sequencing techniques such as microRNAs, circular RNAs, and long non-coding RNAs have been proven as potential therapeutic targets for treating various CVDs. Therapeutics based on RNAs have become a viable option for addressing the intricate molecular pathways that underlie the pathophysiology of CVDs. We provide an in-depth analysis of the state of RNA therapies in the context of CVDs, emphasizing various approaches that target the various stages of the basic dogma of molecular biology to effect temporary or long-term changes. In this review, we summarize recent methodologies used to screen for novel coding and non-coding RNA candidates with diagnostic and treatment possibilities in cardiovascular diseases. These methods include single-cell sequencing techniques, functional RNA screening, and next-generation sequencing.Lastly, we highlighted the potential of using oligonucleotide-based chemical products such as modified RNA and RNA mimics/inhibitors for the treatment of CVDs. Moreover, there will be an increasing number of potential RNA diagnostic and therapeutic for CVDs that will progress to expand for years to come.

A Review of Contemporary and Future Pharmacotherapy for Chronic Heart Failure in Children

This review delves into the most recent therapeutic approaches for pediatric chronic heart failure (HF) as proposed by the International Society for Heart and Lung Transplantation (ISHLT), which are not yet publicly available. The guideline proposes an exhaustive overview of the evolving pharmacological strategies that are transforming the management of HF in the pediatric population. The ISHLT guidelines recognize the scarcity of randomized clinical trials in children, leading to a predominance of consensus-based recommendations, designated as Level C evidence. This review article aims to shed light on the significant paradigm shifts in the proposed 2024 ISHLT guidelines for pediatric HF and their clinical ramifications for pediatric cardiology practitioners. Noteworthy advancements in the updated proposed guidelines include the endorsement of angiotensin receptor-neprilysin inhibitors (ARNIs), sodium-glucose cotransporter 2 inhibitors (SGLT2is), and soluble guanylate cyclase (sGC) stimulators for treating chronic HF with reduced ejection fraction (HFrEF) in children. These cutting-edge treatments show potential for enhancing outcomes in pediatric HFrEF. Nonetheless, the challenge persists in validating the efficacy of therapies proven in adult HFrEF for the pediatric cohort. Furthermore, the proposed ISHLT guidelines address the pharmacological management of chronic HF with preserved ejection fraction (HFpEF) in children, marking a significant step forward in pediatric HF care. This review also discusses the future HF drugs in the pipeline, their mechanism of actions, potential uses, and side effects.

Targeting G protein-coupled receptors for heart failure treatment

Heart failure remains a leading cause of morbidity and mortality worldwide. Current treatment for patients with heart failure include drugs targeting G protein-coupled receptors such as β-adrenoceptor antagonists (β-blockers) and angiotensin II type 1 receptor antagonists (or angiotensin II receptor blockers). However, many patients progress to advanced heart failure with persistent symptoms, despite treatment with available therapeutics that have been shown to reduce mortality and mortality. GPCR targets currently being explored for the development of novel heart failure therapeutics include adenosine receptor, formyl peptide receptor, relaxin/insulin-like family peptide receptor, vasopressin receptor, endothelin receptor and the glucagon-like peptide 1 receptor. Many GPCR drug candidates are limited by insufficient efficacy and/or dose-limiting unwanted effects. Understanding the current challenges hindering successful clinical translation and the potential to overcome existing limitations will facilitate the future development of novel heart failure therapeutics. LINKED ARTICLES: This article is part of a themed issue Therapeutic Targeting of G Protein-Coupled Receptors: hot topics from the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists 2021 Virtual Annual Scientific Meeting. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.14/issuetoc.

Relaxin as a treatment for musculoskeletal fibrosis: What we know and future directions

Fibrotic changes in musculoskeletal diseases arise from the abnormal buildup of fibrotic tissue around the joints, leading to limited mobility, compromised joint function, and diminished quality of life. Relaxin (RLX) attenuates fibrosis by accelerating collagen degradation and inhibiting excessive extracellular matrix (ECM) production. Further, RLX disrupts myofibroblast activation by modulating the TGF-β/Smads signaling pathways, which reduces connective tissue fibrosis. However, the mechanisms and effects of RLX in musculoskeletal pathologies are emerging as increasing research focuses on relaxin's impact on skin, ligaments, tendons, cartilage, joint capsules, connective tissues, and muscles. This review delineates the actions of relaxin within the musculoskeletal system and the challenges to its clinical application. Relaxin shows significant potential in both in vivo and in vitro studies for broadly managing musculoskeletal fibrosis; however, challenges such as short biological half-life and sex-specific responses may pose hurdles for clinical use.

Functional crosstalk between angiotensin receptors (types 1 and 2) and relaxin family peptide receptor 1 (RXFP1): Implications for the therapeutic targeting of fibrosis

Class A, rhodopsin-like, G-protein-coupled receptors (GPCRs) are by far the largest class of GPCRs and are integral membrane proteins used by various cells to convert extracellular signals into intracellular responses. Initially, class A GPCRs were believed to function as monomers, but a growing body of evidence has emerged to suggest that these receptors can function as homodimers and heterodimers and can undergo functional crosstalk to influence the actions of agonists or antagonists acting at each receptor. This review will focus on the angiotensin type 1 (AT1) and type 2 (AT2) receptors, as well as the relaxin family peptide receptor 1 (RXFP1), each of which have their unique characteristics but have been demonstrated to undergo some level of interaction when appropriately co-expressed, which influences the function of each receptor. In particular, this receptor functional crosstalk will be discussed in the context of fibrosis, the tissue scarring that results from a failed wound-healing response to injury, and which is a hallmark of chronic disease and related organ dysfunction. LINKED ARTICLES: This article is part of a themed issue Therapeutic Targeting of G Protein-Coupled Receptors: hot topics from the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists 2021 Virtual Annual Scientific Meeting. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.14/issuetoc.

R2R01: A long-acting single-chain peptide agonist of RXFP1 for renal and cardiovascular diseases

BACKGROUND

The therapeutic potential of relaxin for heart failure and renal disease in clinical trials is hampered by the short half-life of serelaxin. Optimization of fatty acid-acetylated single-chain peptide analogues of relaxin culminated in the design and synthesis of R2R01, a potent and selective RXFP1 agonist with subcutaneous bioavailability and extended half-life.

EXPERIMENTAL APPROACH

Cellular assays and pharmacological models of RXFP1 activation were used to validate the potency and selectivity of R2R01. Increased renal blood flow was used as a translational marker of R2R01 activity. Human mastocytes (LAD2 cells) were used to study potential pseudo-allergic reactions and CD4+ T-cells to study immunogenicity. The pharmacokinetics of R2R01 were characterized in rats and minipigs.

KEY RESULTS

In vitro, R2R01 had comparable potency and efficacy to relaxin as an agonist for human RXFP1. In vivo, subcutaneous administration of R2R01 increased heart rate and renal blood flow in normotensive and hypertensive rat and did not show evidence of tachyphylaxis. R2R01 also increased nipple length in rats, used as a chronic model of RXFP1 engagement. Pharmacokinetic studies showed that R2R01 has a significantly extended terminal half-life. The in vitro assays with LAD2 cells and CD4+ T-cells showed that R2R01 had low potential for pseudo-allergic and immunogenic reactions, respectively.

CONCLUSION AND IMPLICATIONS

R2R01 is a potent RXFP1 agonist with an extended half-life that increases renal blood flow in various settings including normotensive and hypertensive conditions. The preclinical efficacy and safety data supported clinical development of R2R01 as a potential new therapy for renal and cardiovascular diseases.

Cardiomyocyte-specific RXFP1 overexpression protects against pressure overload-induced cardiac dysfunction independently of relaxin

Heart failure (HF) prevalence is rising due to reduced early mortality and demographic change. Relaxin (RLN) mediates protective effects in the cardiovascular system through Relaxin-receptor 1 (RXFP1). Cardiac overexpression of RXFP1 with additional RLN supplementation attenuated HF in the pressure-overload transverse aortic constriction (TAC) model. Here, we hypothesized that robust transgenic RXFP1 overexpression in cardiomyocytes (CM) protects from TAC-induced HF even in the absence of RLN. Hence, transgenic mice with a CM-specific overexpression of human RXFP1 (hRXFP1tg) were generated. Receptor functionality was demonstrated by in vivo hemodynamics, where the administration of RLN induced positive inotropy strictly in hRXFP1tg. An increase in phospholamban-phosphorylation at serine 16 was identified as a molecular correlate. hRXFP1tg were protected from TAC without additional RLN administration, presenting not only less decline in systolic left ventricular (LV) function but also abrogated LV dilation and pulmonary congestion compared to WT mice. Molecularly, transgenic hearts exhibited not only a significantly attenuated fetal and fibrotic gene activation but also demonstrated less fibrotic tissue and CM hypertrophy in histological sections. These protective effects were evident in both sexes. Similar cardioprotective effects of hRXFP1tg were detectable in a RLN-knockout model, suggesting an alternative mechanism of receptor activation through intrinsic activity, alternative endogenous ligands or crosstalk with other receptors. In summary, CM-specific RXFP1 overexpression provides protection against TAC even in the absence of endogenous RLN. This suggests RXFP1 overexpression as a potential therapeutic approach for HF, offering baseline protection with optional RLN supplementation for specific activation.

Vasodilators for Acute Heart Failure - A Systematic Review with Meta-Analysis

BACKGROUND

Acute heart failure is a public health concern. This study systematically reviewed randomized clinical trials (RCTs) to evaluate vasodilators in acute heart failure.

METHODS

The search was conducted across the databases of Medline, Embase, Latin American and the Caribbean Literature on Health Sciences, Web of Science, and the Cochrane Central Register of Controlled Trials. Inclusion criteria consisted of RCTs that compared vasodilators versus standard care, placebo, or cointerventions. The primary outcome was all-cause mortality; secondary outcomes were serious adverse events (SAEs), tracheal intubation, and length of hospital stay. Risk of bias was assessed in all trials.

RESULTS

The study included 46 RCTs that enrolled 28,374 patients with acute heart failure. Vasodilators did not reduce the risk of all-cause mortality (risk ratio, 0.95; 95% confidence interval [CI], 0.87 to 1.04; I2=9.51%; P=0.26). No evidence of a difference was seen in the risk of SAEs (risk ratio, 1.01; 95% CI, 0.97 to 1.05; I2=0.94%) or length of hospital stay (mean difference, -0.10; 95% CI, -0.28 to 0.08; I2=69.84%). Vasodilator use was associated with a lower risk of tracheal intubation (risk ratio, 0.54; 95% CI, 0.30 to 0.99; I2=51.96%) compared with no receipt of vasodilators.

CONCLUSIONS

In this systematic review with meta-analysis of patients with acute heart failure, vasodilators did not reduce all-cause mortality.

Significance of plasma relaxin-2 levels in patients with primary hypertension and type 2 diabetes mellitus

BACKGROUND

This study aimed to evaluate plasma relaxin‑2 (RLN-2) levels in patients with arterial hypertension (AH) and their relationships with clinical and laboratory parameters.

METHODS

The study involved 106 hypertensive patients, including 55 with type 2 diabetes mellitus (T2DM), and 30 control subjects. Plasma RLN-2 levels were measured using an enzyme-linked immunosorbent assay kit.

RESULTS

RLN-2 levels were reduced in patients with AH compared to healthy volunteers (p < 0.001), and hypertensive patients with T2DM had lower RLN-2 levels than those without impaired glucose metabolism (p < 0.001). RLN‑2 was negatively correlated with systolic blood pressure (SBP) (p < 0.001) and anthropometric parameters such as body mass index (BMI; p = 0.027), neck (p = 0.045) and waist (p = 0.003) circumferences, and waist-to-hip ratio (p = 0.011). RLN‑2 also had inverse associations with uric acid levels (p = 0.019) and lipid profile parameters, particularly triglycerides (p < 0.001) and non-HDL-C/HDL‑C (p < 0.001), and a positive relationship with HDL‑C (p < 0.001). RLN‑2 was negatively associated with glucose (p < 0.001), insulin (p = 0.043), HbA1c (p < 0.001), and HOMA-IR index (p < 0.001). Univariate binary logistic regression identified RLN‑2 as a significant predictor of impaired glucose metabolism (p < 0.001).

CONCLUSIONS

Decreased RLN-2 levels in patients with AH and T2DM and established relationships of RLN‑2 with SBP and parameters of glucose metabolism and lipid profile suggest a diagnostic role of RLN‑2 as a biomarker for AH with T2DM.

Endothelial Dysfunction in Heart Failure: What Is Its Role?

The endothelium is a continuous layer of cells that coats the interior walls of arteries, capillaries, and veins. It has an essential regulatory role in hemostatic function, vascular tone, inflammation, and platelet activity. Endothelial dysfunction is characterized by a shift to a proinflammatory and prothrombic state, and it could have a bidirectional relationship with heart failure (HF). Due to neurohormonal activation and shear stress, HFrEF may promote endothelial dysfunction, increase ROS synthesis, and reduce nitric oxide production. Different studies have also shown that endothelium function is damaged in HFpEF because of a systemic inflammatory state. Some clinical trials suggest that drugs that have an effect on endothelial dysfunction in patients with HF or cardiovascular disease may be a therapeutic option. The aim of this review is to highlight the pathogenetic correlation between endothelial dysfunction and heart failure and the related potential therapeutic options.

Identification of Novel Series of Potent and Selective Relaxin Family Peptide Receptor 1 (RXFP1) Agonists

Relaxin H2 is a clinically relevant peptide agonist for relaxin family peptide receptor 1 (RXFP1), but a combination of this hormone's short plasma half-life and the need for injectable delivery limits its therapeutic potential. We sought to overcome these limitations through the development of a potent small molecule (SM) RXFP1 agonist. Although two large SM HTS campaigns failed in identifying suitable hit series, we uncovered novel chemical space starting from the only known SM RXFP1 agonist series, represented by ML290. Following a design-make-test-analyze strategy based on improving early dose to man ranking, we discovered compound 42 (AZ7976), a highly selective RXFP1 agonist with sub-nanomolar potency. We used AZ7976, its 10 000-fold less potent enantiomer 43 and recombinant relaxin H2 to evaluate in vivo pharmacology and demonstrate that AZ7976-mediated heart rate increase in rats was a result of RXFP1 agonism. As a result, AZ7976 was selected as lead for continued optimization.

Current RNA strategies in treating cardiovascular diseases

Cardiovascular disease (CVD) continues to impose a significant global health burden, necessitating the exploration of innovative treatment strategies. Ribonucleic acid (RNA)-based therapeutics have emerged as a promising avenue to address the complex molecular mechanisms underlying CVD pathogenesis. We present a comprehensive review of the current state of RNA therapeutics in the context of CVD, focusing on the diverse modalities that bring about transient or permanent modifications by targeting the different stages of the molecular biology central dogma. Considering the immense potential of RNA therapeutics, we have identified common gene targets that could serve as potential interventions for prevalent Mendelian CVD caused by single gene mutations, as well as acquired CVDs developed over time due to various factors. These gene targets offer opportunities to develop RNA-based treatments tailored to specific genetic and molecular pathways, presenting a novel and precise approach to address the complex pathogenesis of both types of cardiovascular conditions. Additionally, we discuss the challenges and opportunities associated with delivery strategies to achieve targeted delivery of RNA therapeutics to the cardiovascular system. This review highlights the immense potential of RNA-based interventions as a novel and precise approach to combat CVD, paving the way for future advancements in cardiovascular therapeutics.

New Pharmacotherapeutic Classes for the Management of Heart Failure: A Narrative Review

Heart failure (HF) is a syndrome characterized by the heart failing to pump blood to the body at a rate proportional to its needs. HF is a public health burden globally and one of the leading causes of hospitalizations in adults. While many classes of drugs have been introduced for the treatment of HF, not every drug may be well-tolerated by patients. In this narrative review, we describe a few of the newer classes of medications proposed to be efficacious in treating acute and chronic HF. We focus on vericiguat, omecamtiv mecarbil, ularitide, and serelaxin, and thoroughly examine their efficacy and safety profiles while summarizing the clinical trials of the drugs. There is a need for more long-term studies comparing the efficacy of these medications to the conventional ones.

Profile of patients hospitalized in intensive cardiac care units in France: ADDICT-ICCU registry

BACKGROUND

Intensive cardiac care units (ICCU) were initially developed to monitor ventricular arrhythmias after myocardial infarction. In recent decades, ICCU have diversified their activities.

AIM

To determine the type of patients hospitalized in ICCU in France.

METHODS

We analysed the characteristics of patients enrolled in the ADDICT-ICCU registry (NCT05063097), a prospective study of consecutive patients admitted to ICCU in 39 centres throughout France from 7th-22nd April 2021. In-hospital major adverse events (MAE) (death, resuscitated cardiac arrest and cardiogenic shock) were recorded.

RESULTS

Among 1499 patients (median age 65 [interquartile range 54-74] years, 69.6% male, 21.7% diabetes mellitus, 64.7% current or previous smokers), 34.9% had a history of coronary artery disease, 11.7% atrial fibrillation and 5.2% cardiomyopathy. The most frequent reason for admission to ICCU was acute coronary syndromes (ACS; 51.5%), acute heart failure (AHF; 14.1%) and unexplained chest pain (6.8%). An invasive procedure was performed in 36.2%. "Advanced" ICCU therapies were required for 19.9% of patients (intravenous diuretics 18.4%, non-invasive ventilation 6.1%, inotropic drugs 2.3%). No invasive procedures or advanced therapies were required in 44.1%. Cardiac computed tomography or magnetic resonance imaging was carried out in 12.3% of patients. The median length of ICCU hospitalization was 2.0 (interquartile range 1.0-4.0) days. The mean rate of MAE was 4.5%, and was highest in patients with AHF (10.4%).

CONCLUSIONS

ACS remains the main cause of admissions to ICCU, with most having a low rate of in-hospital MAE. Most patients experience a brief stay in ICCU before being discharged home. AHF is associated with highest death rate and with higher resource consumption.

SGLT2 inhibitors in heart failure with preserved ejection fraction

Heart failure (HF) is a clinical syndrome due to either functional or structural impairment of the ventricular pump or filling, representing a major cause of global morbidity and mortality. Heart failure with preserved ejection fraction (HFpEF), characterized by a left ventricular ejection fraction (LVEF) of ≥50%, constitutes over half of the HF population, with a rising prevalence. Until recently, therapeutic options in treating HFpEF and reducing hospitalization and mortality remained limited. Sodium-glucose cotransporter 2 (SGLT2) inhibitors have shown promising results in this patient population. This review article explores current literature and significant clinical trials investigating the impact of sodium- SGLT2 inhibitors in patients with HFpEF.

Cardiac and Renal Fibrosis, the Silent Killer in the Cardiovascular Continuum: An Up-to-Date

Cardiovascular disease (CVD) and chronic kidney disease (CKD) often coexist and have a major impact on patient prognosis. Organ fibrosis plays a significant role in the pathogenesis of cardio-renal syndrome (CRS), explaining the high incidence of heart failure and sudden cardiac death in these patients. Various mediators and mechanisms have been proposed as contributors to the alteration of fibroblasts and collagen turnover, varying from hemodynamic changes to the activation of the renin-angiotensin system, involvement of FGF 23, and Klotho protein or collagen deposition. A better understanding of all the mechanisms involved has prompted the search for alternative therapeutic targets, such as novel inhibitors of the renin-angiotensin-aldosterone system (RAAS), serelaxin, and neutralizing interleukin-11 (IL-11) antibodies. This review focuses on the molecular mechanisms of cardiac and renal fibrosis in the CKD and heart failure (HF) population and highlights the therapeutic alternatives designed to target the responsible pathways.

Hydralazine combined with conventional therapy improved outcomes in severe systolic dysfunction and mitral regurgitation

AIMS

Patients with heart failure (HF) and reduced left ventricular ejection fraction (LVEF) accompanied by significant mitral regurgitation (MR) had poor outcome. Several vasodilator trials showed neutral results. We aimed to investigate the effect of early up-titration of hydralazine combined with conventional treatment in acute HF with severe systolic dysfunction and significant MR.

METHODS AND RESULTS

The study was open-labelled, one-to-one ratio randomized designed. Consecutively hospitalized patients with decompensated HF symptoms, LVEF < 35%, and MR more than moderate severity were enrolled after exclusion. All participants with inadequate preload should have intake promotion with/without fluid supply. Patients receiving evidence-based medications (EBMs) as conventional treatment served as the control. Hydralazine + conventional treatment group received up-titration of hydralazine at Days 1-5 of the index admission combined with EBMs and throughout the course of follow-up. The endpoints included cardiovascular (CV) death and HF rehospitalization. Totally, 408 patients were enrolled (203 in conventional treatment and 205 in hydralazine + conventional treatment). The mean follow-up period was 3.5 years. The mean dose of hydralazine was 191 mg at index admission and 264 mg at study end in hydralazine + conventional treatment group. Both groups did not significantly differ in prescription rates and dosages of EBMs (all P > 0.05) at study end. Side effects did not differ between the two groups. Finally, 51% (104 out of 203 cases) reached endpoints in conventional group and 34.6% (71 out of 205 cases) in hydralazine + conventional treatment group, which had a significant reduction in CV events (hazard ratio 0.613, 95% confidence interval 0.427-0.877, P < 0.001). In-hospital death during the index admission was significantly higher in conventional group (5.4% vs. 0.5%, respectively; P = 0.001).

CONCLUSIONS

When administered without inadequate preload, combining early up-titration of hydralazine with EBMs improves outcome in patients with severe systolic dysfunction and significant MR, and it is safe and well tolerated.

The diverse influences of relaxin-like peptide family on tumor progression: Potential opportunities and emerging challenges

Relaxin-like peptide family exhibit differential expression patterns in various types of cancers and play a role in cancer development. This family participates in tumorigenic processes encompassing proliferation, migration, invasion, tumor microenvironment, immune microenvironment, and anti-cancer resistance, ultimately influencing patient prognosis. In this review, we explore the mechanisms underlying the interaction between the RLN-like peptide family and tumors and provide an overview of therapeutic approaches utilizing this interaction.

Vulnerable period in heart failure: a window of opportunity for the optimization of treatment - a statement by Mexican experts

Acute heart failure (HF) is associated with poor prognosis. After the acute event, there is a vulnerable period during which the patient has a marked risk of readmission or death. Therefore, early optimization of treatment is mandatory during the vulnerable period. The objective of this article is to provide recommendations to address the management of patients with HF during the vulnerable period from a practical point of view. A group of Mexican experts met to prepare a consensus document. The vulnerable period, with a duration of up to 6 months after the acute event - either hospitalization, visit to the emergency department or the outpatient clinic/day hospital - represents a real window of opportunity to improve outcomes for these patients. To best individualize the recommendations, the management strategies were divided into three periods (early, intermediate and late vulnerable period), including not only therapeutic options but also evaluation and education. Importantly, the recommendations are addressed to the entire cardiology team, including physicians and nurses, but also other specialists implicated in the management of these patients. In conclusion, this document represents an opportunity to improve the management of this population at high risk, with the aim of reducing the burden of HF.

Standardized Definitions for Evaluation of Acute Decompensated Heart Failure Therapies: HF-ARC Expert Panel Paper

Acute decompensated heart failure (ADHF) is one of the most common reasons for hospitalizations or urgent care and is associated with poor outcomes. Therapies shown to improve outcomes are limited, however, and innovation in pharmacologic and device-based therapeutics are therefore actively being sought. Standardizing definitions for ADHF and its trajectory is complex, limiting the generalizability and translation of clinical trials to effect clinical care and policy change. The Heart Failure Collaboratory is a multistakeholder organization comprising clinical investigators, clinicians, patients, government representatives (including U.S. Food and Drug Administration and National Institutes of Health participants), payors, and industry collaborators. The following expert consensus document is the product of the Heart Failure Collaboratory convening with the Academic Research Consortium, including members from academia, the U.S. Food and Drug Administration, and industry, for the purposes of proposing standardized definitions for ADHF and highlighting important endpoint considerations to inform the design and conduct of clinical trials for drugs and devices in this clinical arena.

Impact of vasodilators on diuretic response in patients with congestive heart failure: A mechanistic trial of cimlanod (BMS-986231)

AIM

To investigate the effects of Cimlanod, a nitroxyl donor with vasodilator properties, on water and salt excretion after an administration of an intravenos bolus of furosemide.

METHODS AND RESULTS

In this randomized, double-blind, mechanistic, crossover trial, 21 patients with left ventricular ejection fraction <45%, increased plasma concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and receiving loop diuretics were given, on separate study days, either an 8 h intravenous (IV) infusion of cimlanod (12 μg/kg/min) or placebo. Furosemide was given as a 40 mg IV bolus four hours after the start of infusion. The primary endpoint was urine volume in the 4 h after the bolus of furosemide during infusion of cimlanod compared with placebo. Median NT-proBNP at baseline was 1487 (interquartile range: 847-2665) ng/L. Infusion of cimlanod increased cardiac output and reduced blood pressure without affecting cardiac power index consistent with its vasodilator effects. Urine volume in the 4 h post-furosemide was lower with cimlanod (1032 ± 393 ml) versus placebo (1481 ± 560 ml) (p = 0.002), as were total sodium excretion (p = 0.004), fractional sodium excretion (p = 0.016), systolic blood pressure (p < 0.001), estimated glomerular filtration rate (p = 0.012), and haemoglobin (p = 0.010), an index of plasma volume expansion.

CONCLUSIONS

For patients with heart failure and congestion, vasodilatation with agents such as cimlanod reduces the response to diuretic agents, which may offset any benefit from acute reductions in cardiac preload and afterload.

Managing hypertension in African Americans with heart failure: A guide for the primary care clinician

Hypertension is the predominant risk factor for cardiovascular disease related morbidity and mortality among Black adults in the United States. It contributes significantly to the development of heart failure and increases the risk of death following heart failure diagnosis. It is also a leading predisposing factor for hypertensive disorders of pregnancy and peripartum cardiomyopathy in Black women. As such, all stakeholders including health care providers, particularly primary care clinicians (including physicians and advanced practice providers), patients, and communities must be aware of the consequences of uncontrolled hypertension among Black adults. Appropriate treatment strategies should be identified and implemented to ensure timely and effective blood pressure management among Black individuals, particularly those with, and at risk for heart failure.

Acute heart failure: mechanisms and pre-clinical models-a Scientific Statement of the ESC Working Group on Myocardial Function

While chronic heart failure (CHF) treatment has considerably improved patient prognosis and survival, the therapeutic management of acute heart failure (AHF) has remained virtually unchanged in the last decades. This is partly due to the scarcity of pre-clinical models for the pathophysiological assessment and, consequently, the limited knowledge of molecular mechanisms involved in the different AHF phenotypes. This scientific statement outlines the different trajectories from acute to CHF originating from the interaction between aetiology, genetic and environmental factors, and comorbidities. Furthermore, we discuss the potential molecular targets capable of unveiling new therapeutic perspectives to improve the outcome of the acute phase and counteracting the evolution towards CHF.

Acute Heart Failure Is a Malignant Process: But We Can Induce Remission

Acute heart failure is a common and increasingly prevalent condition, affecting >10 million people annually. For those patients who survive to discharge, early readmissions and death rates are >30% everywhere on the planet, making it a malignant condition. Beyond these adverse outcomes, it represents one of the largest drivers of health care costs globally. Studies in the past 2 years have demonstrated that we can induce remissions in this malignant process if therapy is instituted rapidly, at the first acute heart failure episode, using full doses of all available effective medications. Multiple studies have demonstrated that this goal can be achieved safely and effectively. Now the urgent call is for all stakeholders, patients, physicians, payers, politicians, and the public at large to come together to address the gaps in implementation and enable health care providers to induce durable remissions in patients with acute heart failure.

Safety and Performance of the Aortix Device in Acute Decompensated Heart Failure and Cardiorenal Syndrome

BACKGROUND

Cardiorenal syndrome (CRS) complicates 33% of acute decompensated heart failure (ADHF) admissions, and patients with persistent congestion at discharge have high 30-day event rates.

OBJECTIVES

The purpose of this study was to evaluate a novel catheter-deployed intra-aortic entrainment pump (IAEP) in patients with ADHF with CRS and persistent congestion.

METHODS

A multicenter (n = 14), nonrandomized, single-arm, safety and feasibility study of IAEP therapy was conducted. Within patient changes (post-pre IAEP therapy) in fluid loss, hemodynamics, patient-reported dyspnea, and serum biomarkers were assessed using Wilcoxon signed-rank testing.

RESULTS

Of 21 enrolled patients, 18 received Aortix therapy. Mean ± SD patient age was 60.3 ± 7.9 years. The median left ventricular ejection fraction was 22.5% (25th-75th percentile: 10.0%-53.5%); 27.8% had a left ventricular ejection fraction ≥50%. Pre-therapy, patients received 8.7 ± 4.1 days of loop diuretic agents and 44% were on inotropes. Pump therapy averaged 4.6 ± 1.6 days, yielding net fluid losses of 10.7 ± 6.5 L (P < 0.001) and significant (P < 0.01) reductions in central venous pressure (change from baseline: -8.5 mm Hg [25th-75th percentile: -3.5 to -10.0 mm Hg]), pulmonary capillary wedge pressure (-11.0 mm Hg [25th-75th percentile: -5.0 to -14.0 mm Hg]), and serum creatinine (-0.2 mg/dL [25th-75th percentile: -0.1 to -0.5 mg/dL]) with improved estimated glomerular filtration rate (+5.0 mL/min/1.73 m2 [25th-75th percentile: 2.0-9.0 mL/min/1.73 m2]) and patient-reported dyspnea score (+16 [25th-75th percentile: 3-37]). Dyspnea scores, natriuretic peptides, and renal function improvements persisted through 30 days.

CONCLUSIONS

This pilot study of patients with ADHF, persistent congestion, and worsening renal function due to CRS supports the potential for safely achieving decongestion using IAEP therapy. These initial promising results provide the basis for future randomized clinical trials of this novel pump. (An Evaluation of the Safety and Performance of the Aortix System for Intra-Aortic Mechanical Circulatory Support in Patients with Cardiorenal Syndrome [The Aortix CRS Pilot Study]; NCT04145635).

Emerging Individualized Approaches in the Management of Acute Cardiorenal Syndrome With Renal Assist Devices

Growing insights into the pathophysiology of acute cardiorenal syndrome (CRS) in acute decompensated heart failure have indicated that not every rise in creatinine is associated with adverse outcomes. Detection of persistent volume overload and diuretic resistance associated with creatinine rise may identify patients with true acute CRS. More in-depth phenotyping is needed to identify pathologic processes in renal arterial perfusion, venous outflow, and microcirculatory-interstitial-lymphatic axis alterations that can contribute to acute CRS. Recently, various novel device-based interventions designed to target different pathophysiologic components of acute CRS are in early feasibility and proof-of-concept studies. However, appropriate trial endpoints that reflect improvement in cardiorenal trajectories remain elusive and highly debated. In this review the authors describe the variety of physiological derangements leading to acute CRS and the opportunity to individualize the management of acute CRS with novel renal assist devices that can target specific components of these alterations.

Bioactive Compounds and Cardiac Fibrosis: Current Insight and Future Prospect

Cardiac fibrosis is a pathological condition characterized by excessive deposition of collagen and other extracellular matrix components in the heart. It is recognized as a major contributor to the development and progression of heart failure. Despite significant research efforts in characterizing and identifying key molecular mechanisms associated with myocardial fibrosis, effective treatment for this condition is still out of sight. In this regard, bioactive compounds have emerged as potential therapeutic antifibrotic agents due to their anti-inflammatory and antioxidant properties. These compounds exhibit the ability to modulate fibrogenic processes by inhibiting the production of extracellular matrix proteins involved in fibroblast to myofibroblast differentiation, or by promoting their breakdown. Extensive investigation of these bioactive compounds offers new possibilities for preventing or reducing cardiac fibrosis and its detrimental consequences. This comprehensive review aims to provide a thorough overview of the mechanisms underlying cardiac fibrosis, address the limitations of current treatment strategies, and specifically explore the potential of bioactive compounds as therapeutic interventions for the treatment and/or prevention of cardiac fibrosis.

Safety, tolerability and efficacy of up-titration of guideline-directed medical therapies for acute heart failure in elderly patients: A sub-analysis of the STRONG-HF randomized clinical trial

AIMS

STRONG-HF examined a high-intensity care (HIC) strategy of rapid up-titration of guideline-directed medical therapy (GDMT) and close follow-up after acute heart failure (AHF) admission. We assess the role of age on efficacy and safety of HIC.

METHODS AND RESULTS

Hospitalized AHF patients, not treated with optimal GDMT were randomized to HIC or usual care. The primary endpoint of 180-day death or HF readmission occurred equally in older (>65 years, n = 493, 74 ± 5 years) and younger patients (53 ± 11 years, adjusted hazard ratio [aHR] 1.02, 95% confidence interval [CI] 0.73-1.43, p = 0.89). Older patients received slightly lower GDMT to day 21, but same doses at day 90 and 180. The effect of HIC on the primary endpoint was numerically higher in younger (aHR 0.51, 95% CI 0.32-0.82) than older patients (aHR 0.73, 95% CI 0.46-1.15, adjusted interaction p = 0.30), partially related to COVID-19 deaths. After exclusion of COVID-19 deaths, the effect of HIC was similar in younger (aHR 0.51, 95% CI 0.32-0.82) and older patients (aHR 0.63, 95% CI 0.32-1.02, adjusted interaction p = 0.56), with no treatment-by-age interaction (interaction p = 0.57). HIC induced larger improvements in quality of life to day 90 in younger (EQ-VAS adjusted-mean difference 5.51, 95% CI 3.20-7.82) than in older patients (1.77, 95% CI -0.75 to 4.29, interaction p = 0.032). HIC was associated with similar rates of adverse events in older and younger patients.

CONCLUSION

High-intensity care after AHF was safe and resulted in a significant reduction of all-cause death or HF readmission at 180 days across the study age spectrum. Older patients have smaller benefits in terms of quality of life.

Sodium-glucose cotransporter 2 inhibitors and cardiovascular clinical outcomes in acute heart failure: A narrative review

PURPOSE

This review describes the evidence from randomized controlled trials (RCTs) regarding the effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors on cardiovascular (CV) clinical outcomes when therapy is initiated during acute heart failure (HF).

SUMMARY

SGLT2 inhibitors have become a cornerstone of guideline-directed medical therapy (GDMT) for type 2 diabetes mellitus, chronic kidney disease, and HF. Because of their ability to promote natriuresis and diuresis as well as other potentially beneficial CV effects, use of SGLT2 inhibitors has been investigated when therapy is initiated during hospitalization for acute HF. We identified 5 placebo-controlled RCTs that reported CV clinical outcomes incorporating one or more components of all-cause mortality, CV mortality, CV hospitalization, HF worsening, and hospitalization for HF in patients treated with empagliflozin (n = 3 trials), dapagliflozin (n = 1 trial), and sotagliflozin (n = 1 trial). Nearly all CV outcomes in these trials showed benefit with SGLT2 inhibitor use during acute HF. Incidence of hypotension, hypokalemia, and acute renal failure was generally similar to that with placebo. These findings are limited by heterogeneous outcome definitions, variation in time to SGLT2 inhibitor initiation, and small sample sizes.

CONCLUSION

SGLT2 inhibitors may have a role in inpatient management of acute HF, provided there is close monitoring for fluctuations in hemodynamic, fluid, and electrolyte status. Initiation of SGLT2 inhibitors at the time of acute HF may promote optimized GDMT, continued medication adherence, and reduced risk of CV outcomes.

Heart Failure Management Capability and Exacerbation of Heart Failure - A 6-Month Prospective Cohort Study

Background: In households with older individuals, where a patient is experiencing heart failure (HF), effective cooperation between patients and caregivers is crucial for disease management. However, there is limited evidence regarding the impact of cooperative HF management on the incidence of exacerbation. Therefore, the aim of this 6-month prospective cohort study was to investigate the association between HF management capability and exacerbations. Methods and Results: The study enrolled outpatients (age ≥65 years) with chronic HF from a cardiology clinic and their caregivers. Self-care capabilities among patients and caregivers were evaluated using the Self-Care of Heart Failure Index (SCHFI) and Caregiver Contribution-SCHFI, respectively. Total scores were calculated using the highest score for each item. During the follow-up period, 31 patients experienced worsening HF. The analysis revealed no significant association between the total HF management score and HF exacerbation among all eligible patients. However, in patients with preserved left ventricular ejection fraction (LVEF), high HF management capability of the family unit was associated with a reduced risk of HF exacerbation, even after adjusting for the severity of HF. Conclusions: In older patients with HF and preserved LVEF, effective HF management may contribute to a lower risk of exacerbations.

Development of Novel High-Affinity Antagonists for the Relaxin Family Peptide Receptor 1

H2 relaxin is a peptide hormone that exerts its biological actions through the G protein-coupled receptor, RXFP1. The numerous important biological functions of H2 relaxin, including potent renal, vasodilatory, cardioprotective, and anti-fibrotic actions, have resulted in considerable interest in its use as a therapeutic for various cardiovascular diseases and other fibrotic indications. Interestingly though, H2 relaxin and RXFP1 have been shown to be overexpressed in prostate cancer, allowing for the downregulation or blocking of relaxin/RXFP1 to decrease prostate tumor growth. These findings suggest the application of an RXFP1 antagonist for the treatment of prostate cancer. However, these therapeutically relevant actions are still poorly understood and have been hindered by the lack of a high-affinity antagonist. In this study, we chemically synthesized three novel H2 relaxin analogues that have complex insulin-like structures with two chains (A and B) and three disulfide bridges. We report here the structure-activity relationship studies on H2 relaxin that resulted in the development of a novel high-affinity RXFP1 antagonist, H2 B-R13HR (∼40 nM), that has only one extra methylene group in the side chain of arginine 13 in the B-chain (ArgB13) of H2 relaxin. Most notably, the synthetic peptide was shown to be active in a mouse model of prostate tumor growth in vivo where it inhibited relaxin-mediated tumor growth. Our compound H2 B-R13HR will be an important research tool to understand relaxin actions through RXFP1 and may be a potential lead compound for the treatment of prostate cancer.