Serelaxin, recombinant human relaxin-2, for treatment of acute heart failure (RELAX-AHF): a randomised, placebo-controlled trial

Reperfusion therapy with recombinant human relaxin-2 (Serelaxin) attenuates myocardial infarct size and NLRP3 inflammasome following ischemia/reperfusion injury via eNOS-dependent mechanism

Aims

The preconditioning-like infarct-sparing and anti-inflammatory effects of the peptide hormone relaxin following ischemic injury have been studied in the heart. Whether reperfusion therapy with recombinant human relaxin-2, serelaxin, reduces myocardial infarct size and attenuates the subsequent NLRP3 inflammasome activation leading to further loss of functional myocardium following ischemia/reperfusion (I/R) injury is unknown.

Methods and results

After baseline echocardiography, adult male wild-type C57BL or eNOS knockout mice underwent myocardial infarction (MI) by coronary artery ligation for 30 min followed by 24 h reperfusion. Mice were treated with either serelaxin (10 µg/kg; sc) or saline 1 h prior to ischemia or 5 min before reperfusion. In both pre-treatment and reperfusion therapy arms, serelaxin improved survival at 24 h post MI in wild-type mice (79% and 82%) as compared with controls (46% and 50%, P = 0.01), whereas there was no difference in survival between serelaxin- and saline-treated eNOS knockout mice. Moreover, serelaxin significantly reduced infarct size (64% and 67% reduction, P < 0.05), measured with TTC staining, and preserved LV fractional shortening (FS) and end-systolic diameter (LVESD) in wild-type mice as compared with controls (P < 0.05). Interestingly, caspase-1 activity in the heart tissue, a measure of inflammasome formation, was markedly reduced in serelaxin-treated wild-type mice compared with controls at 24 h post-MI in both treatment modalities (P < 0.05). Genetic deletion of eNOS abolished the infarct-sparing and anti-inflammatory effects of serelaxin as well as functional preservation. Serelaxin plasma levels assessed at 5 min and 1 h after treatment, using ELISA, approximated physiologic relaxin levels during pregnancy in mice and parallels that in humans.

Conclusion

Serelaxin attenuates myocardial I/R injury and the subsequent caspase-1 activation via eNOS-dependent mechanism.

Optimizing Hypertensive Acute Heart Failure Management with Afterload Reduction

PURPOSE OF REVIEW

In spite of advances in our understanding of acute heart failure (AHF) and its different phenotypic expressions, AHF management is still centered on volume removal with intravenous diuretics. This narrative review describes the pathophysiology underlying hypertensive AHF and appraises therapies targeting these mechanisms.

RECENT FINDINGS

Vascular redistribution rather than volume overload may be the primary determinant of elevated cardiac filling pressures and subsequent pulmonary congestion in patients with hypertensive AHF; in these patients, vasodilators should be the predominant treatment. Additional therapy with diuretics in hypertensive AHF should be relegated to the treatment of overt volume overload or persistent congestion in spite of optimized hemodynamics. Intravenous nitroglycerin at high doses can rapidly achieve pulmonary decongestion and reduce downstream critical care needs in these patients. The therapeutic role for synthetic peptides with vasodilator properties has yet to be defined. Evidence supporting both old and new vasodilator therapies is limited by a paucity of well-designed studies and failure to demonstrate improvement in long-term outcomes. Targeted study of this phenotype of AHF is needed before vasodilator therapies become incorporated into treatment guidelines.

Serelaxin as a novel therapeutic opposing fibrosis and contraction in lung diseases

The most common therapies for asthma and other chronic lung diseases are anti-inflammatory agents and bronchodilators. While these drugs oppose disease symptoms, they do not reverse established structural changes in the airways and their therapeutic efficacy is reduced with increasing disease severity. The peptide hormone, relaxin, is a Relaxin Family Peptide Receptor 1 (RXFP1) receptor agonist with unique combined effects in the lung that differentiates it from these existing therapies. Relaxin has previously been reported to have cardioprotective effects in acute heart failure as well anti-fibrotic actions in several organs. This review focuses on recent experimental evidence of the beneficial effects of chronic relaxin treatment in animal models of airways disease demonstrating inhibition of airway hyperresponsiveness and reversal of established fibrosis, consistent with potential therapeutic benefit. Of particular interest, accumulating evidence demonstrates that relaxin can also acutely oppose contraction by reducing the release of mast cell-derived bronchoconstrictors and by directly eliciting bronchodilation. When used in combination, chronic and acute treatment with relaxin has been shown to enhance responsiveness to both glucocorticoids and β₂-adrenoceptor agonists respectively. While the mechanisms underlying these beneficial actions remain to be fully elucidated, translation of these promising combined preclinical findings is critical in the development of relaxin as a novel alternative or adjunct therapeutic opposing multiple aspects of airway pathology in lung diseases.

Withaferin A Associated Differential Regulation of Inflammatory Cytokines

A role of inflammation-associated cytokines/chemokines has been implicated in a wide variety of human diseases. Here, we investigated the regulation of inflammatory cytokines released by monocyte-derived THP-1 cells following treatment with the dietary agent withaferin A (WFA). Membrane-based cytokine array profiling of the culture supernatant from adenosine triphosphate-stimulated WFA-treated THP-1 cells showed differential regulation of multiple cytokines/chemokines. A selected group of cytokines/chemokines [interleukin-1 beta (IL-1β), CCL2/MCP-1, granulocyte-macrophage colony stimulating factor, PDGF-AA, PTX3, cystatin-3, relaxin-2, TNFRSF8/CD30, and ACRP30] was validated at the transcription level using qPCR. In silico analysis for transcriptional binding factors revealed the presence of nuclear factor-kappa B (NF-κB) in a group of downregulated cytokine gene promoters. WFA treatment of THP-1 cells blocks the nuclear translocation of NF-kB and corresponds with the reduced levels of cytokine secretion. To further understand the differential expression of cytokines/chemokines, we showed that WFA alters the nigericin-induced co-localization of NLRP3 and ASC proteins, thereby inhibiting caspase-1 activation, which is responsible for the cleavage and maturation of pro-inflammatory cytokines IL-1β and IL-18. These data suggest that dietary agent WFA concurrently targets NF-κB and the inflammasome complex, leading to inhibition of IL-1β and IL-18, respectively, in addition to differential expression of multiple cytokines/chemokines. Taken together, these results provide a rationale for using WFA to further explore the anti-inflammatory mechanism of cytokines/chemokines associated with inflammatory diseases.

Serial Sonographic Assessment of Pulmonary Edema in Patients With Hypertensive Acute Heart Failure

OBJECTIVES

Objective measures of clinical improvement in patients with acute heart failure (AHF) are lacking. The aim of this study was to determine whether repeated lung sonography could semiquantitatively capture changes in pulmonary edema (B-lines) in patients with hypertensive AHF early in the course of treatment.

METHODS

We conducted a feasibility study in a cohort of adults with acute onset of dyspnea, severe hypertension in the field or at triage (systolic blood pressure ≥ 180 mm Hg), and a presumptive diagnosis of AHF. Patients underwent repeated dyspnea and lung sonographic assessments using a 10-cm visual analog scale (VAS) and an 8-zone scanning protocol. Lung sonographic assessments were performed at the time of triage, initial VAS improvement, and disposition from the emergency department. Sonographic pulmonary edema was independently scored offline in a randomized and blinded fashion by using a scoring method that accounted for both the sum of discrete B-lines and degree of B-line fusion.

RESULTS

Sonographic pulmonary edema scores decreased significantly from initial to final sonographic assessments (P < .001). The median percentage decrease among the 20 included patient encounters was 81% (interquartile range, 55%-91%). Although sonographic pulmonary edema scores correlated with VAS scores (ρ = 0.64; P < .001), the magnitude of the change in these scores did not correlate with each other (ρ = -0.04; P = .89).

CONCLUSIONS

Changes in sonographic pulmonary edema can be semiquantitatively measured by serial 8-zone lung sonography using a scoring method that accounts for B-line fusion. Sonographic pulmonary edema improves in patients with hypertensive AHF during the initial hours of treatment.

In-hospital worsening heart failure: a clinically relevant endpoint?

Outcome measures used for the clinical evaluation of patients with acute heart failure differ between studies and may neither adequately address the characteristic presenting symptoms and signs nor reflect the pathophysiological processes involved. In-hospital worsening of heart failure (WHF) is associated with poor outcomes and thus a potential endpoint conveying clinically meaningful prognostic information. Current definitions of WHF are based on the combination of worsening symptoms and signs and the intensification of treatment during admission. Definitions vary across studies and do not fully account for baseline therapy or circumstances in which there is failure to respond to treatment. Further, there are limited data to inform healthcare professionals as to which patients are most at risk of developing in-hospital WHF. In this opinion piece, we review the definitions for WHF used in recent and ongoing clinical trials and propose a novel definition, which captures failure to respond to treatment as well as clinical worsening (deterioration of symptoms and signs) of the patient's condition. Such a definition, applied consistently across studies, would help clarify the characteristics of patients likely to develop in-hospital WHF, allow comparative assessments of the effectiveness of interventions, and help guide appropriate patient management in order to improve outcomes.

Acute Heart Failure: Definition, Classification and Epidemiology

Purpose of Review

The purpose of this review is to describe the extent and scope of acute heart failure (AHF), place it within its clinical context and highlight some of the difficulties in defining it as a pathophysiological entity.

Recent Findings

A diagnosis of AHF is made when patients present acutely with signs and symptoms of heart failure, often with decompensation of pre-existing cardiomyopathy. The most current guidelines classify based on clinical features at initial presentation and are used to both risk stratify and guide the management of haemodynamic compromise. Despite this, AHF remains a diagnosis with a poor prognosis and there is no therapy proven to have long-term mortality benefits.

Summary

We provide an introduction to AHF and discuss its definition, causes and precipitants. We also present epidemiological and demographic data to suggest that there is significant patient heterogeneity and that AHF is not a single pathology, but rather a range of pathophysiological entities. This poses a challenge when designing clinical trials and may, at least in part, explain why the results in this area have been largely disappointing.

Relaxin reverses inflammatory and immune signals in aged hearts

Background

‘Healthy’ aging drives structural and functional changes in the heart including maladaptive electrical remodeling, fibrosis and inflammation, which lower the threshold for cardiovascular diseases such as heart failure (HF) and atrial fibrillation (AF). Despite mixed results in recent clinical trials, Relaxin-therapy for 2-days could reduce mortality by 37% at 180-days post-treatment, in patients with acute decompensated HF. Relaxin’s short life-span (hours) but long-lasting protective actions led us to test the hypothesis that relaxin acts at a genomic level to reverse maladaptive remodeling in aging and HF.

Methods and results

Young (9-month) and aged (24-month), male and female F-344/Brown Norway rats were treated with relaxin (0.4 mg/kg/day) for 2-weeks delivered by subcutaneous osmotic mini-pumps or with sodium acetate (controls). The genomic effects of aging and relaxin were evaluated by extracting RNA from the left ventricles and analyzing genomic changes by RNA-sequencing, Ingenuity Pathway Analysis, MetaCore and tissue immunohistochemistry. We found that aging promotes a native inflammatory response with distinct sex-differences and relaxin suppresses transcription of multiple genes and signaling pathways associated with inflammation and HF in both genders. In addition, aging significantly increased: macrophage infiltration and atrial natriuretic peptide levels in female ventricles, and activation of the complement cascade, whereas relaxin reversed these age-related effects.

Conclusion

These data support the hypothesis that relaxin alters gene transcription and suppresses inflammatory pathways and genes associated with HF and aging. Relaxin’s suppression of inflammation and fibrosis supports its potential as a therapy for cardiovascular and inflammation-related diseases, such as HF, AF and diabetes.

A Human Study to Evaluate Safety, Tolerability, and Cyclic GMP Activating Properties of Cenderitide in Subjects With Stable Chronic Heart Failure

Cenderitide is a novel designer natriuretic peptide (NP) composed of C‐type natriuretic peptide (CNP) fused to the C‐terminus of Dendroaspis natriuretic peptide (DNP). Cenderitide was engineered to coactivate the two NP receptors, particulate guanylyl cyclase (pGC)‐A and ‐B. The rationale for its design was to achieve the renal‐enhancing and antifibrotic properties of dual receptor activation, but without clinically significant hypotension. Here we report the first clinical trial on the safety, tolerability, and cyclic guanosine monophosphate (cGMP) activating properties of Cenderitide in subjects with stable heart failure (HF). Four‐hour infusion of Cenderitide was safe, well‐tolerated, and significantly increased plasma cGMP levels and urinary cGMP excretion without adverse effects with no change in blood pressure. Thus, Cenderitide has a favorable safety profile and expected pharmacological effects in stable human HF. Our results support further investigations of Cenderitide in HF as a potential future cGMP‐enhancing therapeutic strategy.

Trends in Premature Mortality Due to Heart Failure by Autonomous Community in Spain: 1999 to 2013

INTRODUCTION AND OBJECTIVES

Heart failure (HF) is a major public health problem, and the prevalence increases with age. In Spain, there are considerable differences between autonomous communities. The aim of this study was to analyze trends in premature mortality due to HF between 1999 and 2013 in Spain by autonomous community.

METHODS

We analyzed data on mortality due to HF in Spanish residents aged 0 to 75 years by autonomous community between 1999 and 2013. Data were collected from files provided by the Spanish Statistics Office. Age-adjusted mortality rates were analyzed and the average annual percentage rate was estimated by Poisson models.

RESULTS

Mortality due to HF represented 10.9% of total mortality. In 2013, the national age-adjusted rate was 2.98 deaths in men and 1.29 deaths in women per 100 000 inhabitants, with an annual mean reduction of 2.27% and 4.53%, respectively. In men, average mortality showed the greatest reduction in Castile-La-Mancha (6.30%). In Cantabria, average mortality significantly increased (3.97%). In women, average mortality showed the greatest decrease in the Chartered Community of Navarre (15.17%).

CONCLUSIONS

During the study period, mortality due to HF showed an overall average decrease, both nationally and by autonomous community. This decrease was more pronounced in women than in men. Premature mortality significantly decreased in most-but not all-autonomous communities.

Newer hormonal pharmacotherapies for heart failure

INTRODUCTION

Heart failure (HF) is characterized by maladaptive neurohormonal activation of the cardiovascular and renal systems resulting in circulatory inadequacy and frequent acute exacerbations. The increasing burden of HF prompted investigation of underlying pathophysiological mechanisms and the design of pharmacotherapeutics that would target these pathways.

AREAS COVERED

A MEDLINE search for relevant original investigations and review articles of newer hormonal drugs for HF since the year 2005 till October 2017 provided us with necessary literature. Major trials and relevant clinical investigations were discussed.

EXPERT COMMENTARY

A multitude of hormonal pathways central to HF were identified, including the natriuretic peptide system and neurohormones such as relaxin, arginine vasopressin, and endothelin. However, drugs targeting these novel pathways (aliskiren, tolvaptan, ularitide, serelaxin, bosentan, macitentan) failed to show mortality benefit. This emphasizes a tremendous unmet need in the pharmacotherapy for HF, especially for the subtypes of acute HF and HF with preserved ejection fraction. Sacubitril/valsartan demonstrated substantial mortality benefit in chronic systolic HF population and is endorsed by international HF guidelines. If proven to be efficacious in larger outcome trials, finerenone can be a valuable addition baseline HF therapy. More basic, translational, and phenotype specific clinical research is warranted to improve HF pharmacotherapy.

Effects of serelaxin on renal microcirculation in rats under control and high-angiotensin environments

Serelaxin is a novel recombinant human relaxin-2 that has been investigated for the treatment of acute heart failure. However, its effects on renal function, especially on the renal microcirculation, remain incompletely characterized. Our immunoexpression studies localized RXFP1 receptors on vascular smooth muscle cells and endothelial cells of afferent arterioles and on principal cells of collecting ducts. Clearance experiments were performed in male and female normotensive rats and Ang II-infused male rats. Serelaxin increased mean arterial pressure slightly and significantly increased renal blood flow, urine flow, and sodium excretion rate. Group analysis of all serelaxin infusion experiments showed significant increases in GFR. During infusion with subthreshold levels of Ang II, serelaxin did not alter mean arterial pressure, renal blood flow, GFR, urine flow, or sodium excretion rate. Heart rates were elevated during serelaxin infusion alone (37 ± 5%) and in Ang II-infused rats (14 ± 2%). In studies using the in vitro isolated juxtamedullary nephron preparation, superfusion with serelaxin alone (40 ng/ml) significantly dilated afferent arterioles (10.8 ± 1.2 vs. 13.5 ± 1.1 µm) and efferent arterioles (9.9 ± 0.9 vs. 11.9 ± 1.0 µm). During Ang II superfusion, serelaxin did not alter afferent or efferent arteriolar diameters. During NO synthase inhibition (l-NNA), afferent arterioles also did not show any vasodilation during serelaxin infusion. In conclusion, serelaxin increased overall renal blood flow, urine flow, GFR, and sodium excretion and dilated the afferent and efferent arterioles in control conditions, but these effects were attenuated or prevented in the presence of exogenous Ang II and NO synthase inhibitors.

Addressing the Heterogeneity of Heart Failure in Future Randomized Trials

PURPOSE OF THE REVIEW

The aim of review is to describe the essential role of study designs beyond RCTs in contemporary contest of HF patients giving perspectives on its evolving. The article concludes with concern about the support of observational studies for future randomized clinical trials.

RECENT FINDINGS

With the aging population and spectacular advance in cardiovascular therapy, the clinical syndrome comprising heart failure (HF) is increasingly in complexity of heterogeneity. It remains among the most challenging of clinical syndromes with a magnitude of proposed pathophysiological mechanisms involving the heart and the interplay with cardiac and non-cardiac comorbidities. In this epidemiological scenario, randomized clinical trials are suffering from growing failed treatment, so that a deeper understanding of heterogeneity represents a major unmet need. This field also is greatly in a more nuanced comprehension about the applicability in clinical practice of trials' results derived from well-selected HF population. Thus, we need to reflect on trials failures and the translation of previous trials in clinical practice in order to redirect the future trial intervention.

Impact of Site Selection and Study Conduct on Outcomes in Global Clinical Trials

PURPOSE OF REVIEW

There are over 25 million patients living with heart failure globally. Overall, and especially post-discharge, clinical outcomes have remained poor in heart failure despite multiple trials, with both successes and failures over the last two decades. Matching therapies to the right patient population, identifying high-quality sites, and ensuring optimal trial design and execution represent important considerations in the development of novel therapeutics in this space.

RECENT FINDINGS

While clinical trials have undergone rapid globalization, this has come with regional variation in comorbidities, clinical parameters, and even clinical outcomes and treatment effects across international sites. These issues have now highlighted knowledge gaps about the conduct of trials, selection of study sites, and an unmet need to develop and identify "ideal" sites. There is a need for all stakeholders, including academia, investigators, healthcare organizations, patient advocacy groups, industry sponsors, research organizations, and regulatory authorities, to work as a multidisciplinary group to address these problems and develop practical solutions to improve trial conduct, efficiency, and execution. We review these trial-level issues using examples from contemporary studies to inform and optimize the design of future global clinical trials in heart failure.

Pharmacological and Non-pharmacological Treatment for Decompensated Heart Failure: What Is New?

PURPOSE OF THE REVIEW

Acute heart failure (AHF) is a life-threatening clinical condition that requires prompt medical attention. The aim of the current review is to summarise the results of recent clinical trials conducted in patients with AHF.

RECENT FINDINGS

Several novel compounds have apparently beneficial acute effects on cardiovascular haemodynamics and patients' symptoms, but their administration has not yet translated into improved survival and has been deleterious in some cases. The management of patients with AHF is challenging and reflects the heterogeneity of patient's presentation, the complexity and severity of a multi-organ syndrome, and the limited therapeutic options, usually restricted to a combination of diuretics and vasodilators. Ongoing trials of novel treatments may provide evidence of an effect on outcomes.

Diuretic Strategies in Acute Decompensated Heart Failure

PURPOSE OF REVIEW

The burden of heart failure in the United States is growing rapidly to epic proportions with serious clinical implications for patients and economic strain for healthcare systems. One of the most common reasons for hospitalization in acute decompensated heart failure (ADHF) is excess volume accumulation which leads to untoward symptoms including dyspnea,orthopnea, and edema.

RECENT FINDINGS

Over the past several decades, there has been great interest in exploring various decongestive strategies in order to achieve symptomatic improvement and favorable clinical outcomes. These include different modalities of loop diuretic administration, the adjunctive use of non-loop diuretics, and other diuretic sparing strategies. Herein, we provide an appraisal of these decongestive strategies and discuss novel concepts predicting clinical outcomes based on diuretic response and decongestive adequacy while discussing commonly encountered problems such as worsening renal function in ADHF.

Global Variations in Patient Populations and Outcomes in Heart Failure Clinical Trials

PURPOSE OF REVIEW

Heart failure is a global pandemic and there has been a growing effort to enroll patients from different geographical regions in randomized controlled trials. In this review, we examined regional variation in both patient characteristics and outcomes among several of the most recent global heart failure trials RECENT FINDINGS: Retrospective analyses of global heart failure trials have identified marked variations in both baseline characteristics and management of heart failure by region of enrollment. In some trials, this variation has been significant enough to cause differential treatment effects. We summarized key heterogeneity observed in global heart failure clinical trials. Differences in both patient population and organization of these trials abroad pose an important challenge in making interpretations and country-level decisions. As such, we encourage a concerted effort to account for these differences in future research.

Relaxin contributes to the regulation of arterial pressure in adult female mice

Relaxin is increasingly being recognized as a potent vasodilatory and antifibrotic hormone. Given that relaxin is present in the circulation during the luteal phase of the menstrual cycle and during pregnancy, when arterial pressure is lowest in women, relaxin may contribute to the relative cardiovascular protection observed in premenopausal women as compared with age-matched men and postmenopausal women. In the present study, we investigated the contribution of relaxin to the normal regulation of arterial pressure in adult female and male mice and during pregnancy. Mean arterial pressure (MAP) was measured via radiotelemetry in 14-week-old male and female wild-type (WT; C67BL/6xSv129) and relaxin knockout (KO) mice. Thereafter, female mice were time-mated with a (non-telemetered) male of the same genotype and MAP was measured throughout gestation. Basal MAP was ∼10 mmHg lower in WT females than males (P<0.05). Relaxin deficiency increased basal MAP in females (P<0.05 vs WT female), but not males. As expected, MAP decreased during gestation in WT mice. Conversely, in relaxin KO mice, arterial pressure increased during mid and late gestation (P<0.05 as compared with WT). Moreover, relaxin deficiency impaired gestational weight gain and reduced litter size. This is the first study to (i) demonstrate that relaxin contributes to the sexual dimorphism of arterial pressure in mice and (ii) document the changes in the arterial pressure profile of pregnant relaxin KO mice. Understanding the mechanisms that underlie the regulation of arterial pressure in premenopausal females may uncover new strategies to treat hypertension in women (non-pregnant and pregnant) and men.

Second thoughts on the final rule: An analysis of baseline participant characteristics reports on ClinicalTrials.gov

Background

ClinicalTrials.gov is valuable for aggregate-level analysis of trials. The recently published final rule aims to improve reporting of trial results. We aimed to assess variability in ClinicalTirals.gov records reporting participants’ baseline measures.

Methods and findings

The September 2015 edition of the database for Aggregate Analysis of ClinicalTrials.gov (AACT), was used in this study. To date, AACT contains 186,941 trials of which 16,660 trials reporting baseline (participant) measures were analyzed. We also analyzed a subset of 13,818 Highly Likely Applicable Clinical Trials (HLACT), for which reporting of results is likely mandatory and compared a random sample of 30 trial records to their journal articles. We report counts for each mandatory baseline measure and variability reporting in their formats. The AACT dataset contains 8,161 baseline measures with 1206 unique measurement units. However, of these 6,940 (85%) variables appear only once in the dataset. Age and Gender are reported using many different formats (178 and 49 respectively). “Age” as the variable name is reported in 60 different formats. HLACT subset reports measures using 3,931 variables. The most frequent Age format (i.e. mean (years) ± sd) is found in only 45% of trials. Overall only 4 baseline measures (Region of Enrollment, Age, Number of Participants, and Gender) are reported by > 10% of trials. Discrepancies are found in both the types and formats of ClinicalTrials.gov records and their corresponding journal articles. On average, journal articles include twice the number of baseline measures (13.6±7.1 (sd) vs. 6.6±7.6) when compared to the ClinicalTrials.gov records that report any results.

Conclusions

We found marked variability in baseline measures reporting. This is not addressed by the final rule. To support secondary use of ClinicalTrials.gov, a uniform format for baseline measures reporting is warranted.

Lessons learned in acute heart failure

Acute heart failure (HF) is a global pandemic with more than one million admissions to hospital annually in the US and millions more worldwide. Post-discharge mortality and readmission rates remain unchanged and unacceptably high. Although recent drug development programmes have failed to deliver novel therapies capable of reducing cardiovascular morbidity and mortality in patients hospitalized for worsening chronic HF, hospitalized HF registries and clinical trial databases have generated a wealth of information improving our collective understanding of the HF syndrome. This review will summarize key insights from clinical trials in acute HF and hospitalized HF registries over the last several decades, focusing on improving the management of patients with HF and reduced ejection fraction.

Heart failure

Heart failure is common in adults, accounting for substantial morbidity and mortality worldwide. Its prevalence is increasing because of ageing of the population and improved treatment of acute cardiovascular events, despite the efficacy of many therapies for patients with heart failure with reduced ejection fraction, such as angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), β blockers, and mineralocorticoid receptor antagonists, and advanced device therapies. Combined angiotensin receptor blocker neprilysin inhibitors (ARNIs) have been associated with improvements in hospital admissions and mortality from heart failure compared with enalapril, and guidelines now recommend substitution of ACE inhibitors or ARBs with ARNIs in appropriate patients. Improved safety of left ventricular assist devices means that these are becoming more commonly used in patients with severe symptoms. Antidiabetic therapies might further improve outcomes in patients with heart failure. New drugs with novel mechanisms of action, such as cardiac myosin activators, are under investigation for patients with heart failure with reduced left ventricular ejection fraction. Heart failure with preserved ejection fraction is a heterogeneous disorder that remains incompletely understood and will continue to increase in prevalence with the ageing population. Although some data suggest that spironolactone might improve outcomes in these patients, no therapy has conclusively shown a significant effect. Hopefully, future studies will address these unmet needs for patients with heart failure. Admissions for acute heart failure continue to increase but, to date, no new therapies have improved clinical outcomes.

Prognostic Value of N-Terminal Pro-B-Type Natriuretic Peptide Levels in Heart Failure Patients With and Without Atrial Fibrillation

BACKGROUND

Patients with heart failure (HF) and atrial fibrillation (AF) have higher circulating levels of NT-proBNP (N-terminal pro-B-type natriuretic peptide) than HF patients without AF. There is uncertainty about the prognostic importance of a given concentration of NT-proBNP in HF patients with and without AF. We investigated this question in a large cohort of patients with HF and reduced ejection fraction.

METHODS AND RESULTS

We studied 14 737 patients with HF and reduced ejection fraction and a measurement of NT-proBNP at time of screening, enrolled in either the PARADIGM-HF trial (Prospective Comparison of ARNI With ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure) or the ATMOSPHERE trial (Aliskiren Trial to Minimize Outcomes in Patients With Heart Failure), of whom 3575 (24%) had AF on their baseline ECG. Median (Q1, Q3) levels of NT-proBNP were 1817 pg/mL (1095-3266 pg/mL) in those with AF and 1271 pg/mL (703-2569 pg/mL) in those without (P<0.0001). Patients with AF were older (67 versus 62 years), had worse New York Heart Association class (III/IV; 36% versus 24%), and experienced fewer previous HF hospitalizations (52% versus 61%) or myocardial infarction (30% versus 46%); all P<0.001. We categorized patients with and without AF into 5 NT-proBNP bands: <400, 400 to 999 (reference), 1000 to 1999, 2000 to 2999, and ≥3000 pg/mL. For the primary composite outcome of cardiovascular death or HF hospitalization, event rates differed for patients with and without AF in the lowest band (<400 pg/mL; 8.2 versus 5.0 per 100 patient-years), but not for the higher bands (400-999 pg/mL, 7.4 versus 7.7 per 100 patient-years; 1000-1999 pg/mL, 9.8 versus 11.4 per 100 patient-year; 2000-2999 pg/mL, 13.5 versus 13.4 per 100 patient-years; ≥3000 pg/mL, 22.7 versus 23.0 per 100 patient-years). These findings were consistent whether NT-proBNP was examined as a categorical or continuous variable and before and after adjustment for other prognostic variables. We found similar results for the components of the composite outcome and all-cause mortality.

CONCLUSIONS

HF and reduced ejection fraction patients with AF had higher NT-proBNP than those without AF. However, above a concentration of 400 pg/mL (representing most patients in each group), NT-proBNP had similar predictive value for adverse cardiovascular outcomes, irrespective of AF status.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier NCT00853658 (ATMOSPHERE) and NCT01035255 (PARADIGM-HF).

Serelaxin inhibits differentiation and fibrotic behaviors of cardiac fibroblasts by suppressing ALK-5/Smad2/3 signaling pathway

Serelaxin, a recombinant form of human relaxin-2, is currently regarded as a novel drug for treatment of acute heart failure. However, whether therapeutic effects of serelaxin are achieved by inhibiting cardiac fibrosis remains unclear. In this study, we investigate effects of serelaxin on inhibiting cardiac fibrosis. Cardiac fibroblasts (CFs) were isolated from the hearts of adult rats. Effects of serelaxin on differentiation of CFs towards myofibroblasts (MFs) and their fibrotic behaviors after induction with TGF-β1 were examined. Synthesis and degradation of collagens, secretion of IL-10, and expression of ALK-5 and p-Smad2/3 of TGF-β1-induced cells were assessed after treatment with serelaxin. Serelaxin inhibited differentiation of TGF-β1-induced CFs towards MFs, and reduced proliferation and migration of the induced cells. Moreover, serelaxin down-regulated expression of collagen I/III and TIMP-2, and up-regulated expression of MMP-2 and MMP-9 in the cells. After treatment with serelaxin, activity of MMP-2 and MMP-9 and secretion of IL-10 increased, expression of ALK-5 and the level of Smad2/3 phosphorylation was reduced significantly. These results suggest that serelaxin can inhibit differentiation of TGF-β1-induced CFs towards MFs, reduce production of collagens by suppressing ALK-5/Smad2/3 signaling pathway, and enhance extracellular matrix degradation by increasing MMP-2/TIMP-2 ratio and IL-10 secretion. Serelaxin may be a potential therapeutic drug for inhibiting cardiac fibrosis.

Contemporary Management of Cardiogenic Shock: A Scientific Statement From the American Heart Association

Cardiogenic shock is a high-acuity, potentially complex, and hemodynamically diverse state of end-organ hypoperfusion that is frequently associated with multisystem organ failure. Despite improving survival in recent years, patient morbidity and mortality remain high, and there are few evidence-based therapeutic interventions known to clearly improve patient outcomes. This scientific statement on cardiogenic shock summarizes the epidemiology, pathophysiology, causes, and outcomes of cardiogenic shock; reviews contemporary best medical, surgical, mechanical circulatory support, and palliative care practices; advocates for the development of regionalized systems of care; and outlines future research priorities.

Feasibility of Serial 6-min Walk Tests in Patients with Acute Heart Failure

Background: Functional status assessment is common in many cardiovascular diseases but it has undergone limited study in the setting of acute heart failure (AHF). Accordingly, we performed a pilot study of the feasibility of the six-minute walk test (6MWT) at the emergency department (ED) presentation and through the hospitalization in patients with AHF. Methods and Results: From November 2014 to February 2015, we conducted a multicenter, observational study of ED patients, aged 18–85 years, whose primary ED admission diagnosis was AHF. Other criteria for enrollment included a left ventricular ejection fraction ≤40%, systolic blood pressure between 90 and 170 mmHg, and verbal confirmation that the patient was able to walk >30 m at the baseline, prior to ED presentation. Study teams were uniformly trained to administer a 6MWT. Patients underwent a baseline 6MWT within 24 h of ED presentation (Day 1) and follow-up 6MWTs at 24 (Day 2), 48 (Day 3), and 120 h (Day 5). A total of 46 patients (65.2% male, 73.9% African American) had a day one mean walk distance of 137.3 ± 78 m, day 2 of 170.9 ± 100 m, and day 3 of 180.8 ± 98 m. The 6MWT demonstrated good reproducibility, as the distance walked on the first 6MWT on Day 3 was similar to the distance on the repeated 6MWT the same day. Conclusions: Our pilot study demonstrates the feasibility of the 6MWT as a functional status endpoint in AHF patients. A larger study in a more demographically diverse cohort of patients is necessary to confirm its utility and association with 30-day heart failure (HF) events.

In search of a small molecule agonist of the relaxin receptor RXFP1 for the treatment of liver fibrosis

The peptide hormone human relaxin-2 (H2-RLX) has emerged as a potential therapy for cardiovascular and fibrotic diseases, but its short in vivo half-life is an obstacle to long-term administration. The discovery of ML290 demonstrated that it is possible to identify small molecule agonists of the cognate G-protein coupled receptor for H2-RLX (relaxin family peptide receptor-1 (RXFP1)). In our efforts to generate a new medicine for liver fibrosis, we sought to identify improved small molecule functional mimetics of H2-RLX with selective, full agonist or positive allosteric modulator activity against RXFP1. First, we confirmed expression of RXFP1 in human diseased liver. We developed a robust cellular cAMP reporter assay of RXFP1 signaling in HEK293 cells transiently expressing RXFP1. A high-throughput screen did not identify further specific agonists or positive allosteric modulators of RXFP1, affirming the low druggability of this receptor. As an alternative approach, we generated novel ML290 analogues and tested their activity in the HEK293-RXFP1 cAMP assay and the human hepatic cell line LX-2. Differences in activity of compounds on cAMP activation compared with changes in expression of fibrotic markers indicate the need to better understand cell- and tissue-specific signaling mechanisms and their disease-relevant phenotypes in order to enable drug discovery.

Systolic blood pressure reduction during the first 24 h in acute heart failure admission: friend or foe?

AIMS

Changes in systolic blood pressure (SBP) during an admission for acute heart failure (AHF), especially those leading to hypotension, have been suggested to increase the risk for adverse outcomes.

METHODS AND RESULTS

We analysed associations of SBP decrease during the first 24 h from randomization with serum creatinine changes at the last time-point available (72 h), using linear regression, and with 30- and 180-day outcomes, using Cox regression, in 1257 patients in the VERITAS study. After multivariable adjustment for baseline SBP, greater SBP decrease at 24 h from randomization was associated with greater creatinine increase at 72 h and greater risk for 30-day all-cause death, worsening heart failure (HF) or HF readmission. The hazard ratio (HR) for each 1 mmHg decrease in SBP at 24 h for 30-day death, worsening HF or HF rehospitalization was 1.01 [95% confidence interval (CI) 1.00-1.02; P = 0.021]. Similarly, the HR for each 1 mmHg decrease in SBP at 24 h for 180-day all-cause mortality was 1.01 (95% CI 1.00-1.03; P = 0.038). The associations between SBP decrease and outcomes did not differ by tezosentan treatment group, although tezosentan treatment was associated with a greater SBP decrease at 24 h.

CONCLUSIONS

In the current post hoc analysis, SBP decrease during the first 24 h was associated with increased renal impairment and adverse outcomes at 30 and 180 days. Caution, with special attention to blood pressure monitoring, should be exercised when vasodilating agents are given to AHF patients.

Serelaxin improves cardiac and renal function in DOCA-salt hypertensive rats

Serelaxin, a recombinant form of the naturally occurring peptide hormone relaxin-2, is a pleiotropic vasodilating hormone that has been studied in patients with acute heart failure. In this study, the effects of serelaxin on cardiac and renal function, fibrosis, inflammation and lipid accumulation were studied in DOCA-salt treated rats. Uninephrectomized rats were assigned to two groups: controls provided with normal drinking water and DOCA provided with DOCA pellets and sodium chloride drinking water. After 4 weeks, the DOCA-salt rats were randomly selected and implanted with osmotic minipumps delivering vehicle or serelaxin for another 4 weeks. Treatment with serelaxin prevented cardiac and renal dysfunction in DOCA-salt rats. Serelaxin prevented cardiac and renal fibrosis, as determined by Picrosirius Red staining and Second Harmonic Generation (SHG) Microscopy. Treatment of DOCA-salt rats with serelaxin decreased renal inflammation, including the expression of TGF-β, NFκB, MCP-1, IL-1, IL-6, ICAM-1, VCAM-1 and CD68 macrophages. Serelaxin also decreased lipid accumulation in kidney in part by decreasing SREBP-1c, SREBP-2, ChREBP, FATP1, HMGCoAR, and LDL receptor, and increasing Acox1 and ABCA1. In summary, serelaxin reversed DOCA-salt induced cardiac and renal dysfunction.

Effects of Additive Tolvaptan vs. Increased Furosemide on Heart Failure With Diuretic Resistance and Renal Impairment - Results From the K-STAR Study

BACKGROUND

, were randomized into 2 groups and administered either ≤15 mg/day additive tolvaptan (TLV) or ≤40 mg/day increased FUR for 7 days. Changes in urine volume between baseline and mean urine volume during treatment were significantly higher in the TLV than FUR group (P=0.0003). Although there was no significant decrease in body weight or improved signs and symptoms of congestion between the 2 groups, the increase in serum creatinine on Day 7 from baseline was significantly smaller in the TLV than FUR group (P=0.038). Multiple logistic regression analysis revealed that additive TLV (odds ratio 0.157, 95% confidence interval 0.043-0.605, P=0.001) was an independent clinical factor for improved renal function during treatment compared with increased FUR.

CONCLUSIONS

In HF patients with residual congestion and renal dysfunction refractory to standard therapy, additive TLV increased urine volume without further renal impairment compared with patients who received an increased dose of FUR.

Relaxin-2 in Cardiometabolic Diseases: Mechanisms of Action and Future Perspectives

Despite the great effort of the medical community during the last decades, cardiovascular diseases remain the leading cause of death worldwide, increasing their prevalence every year mainly due to our new way of life. In the last years, the study of new hormones implicated in the regulation of energy metabolism and inflammation has raised a great interest among the scientific community regarding their implications in the development of cardiometabolic diseases. In this review, we will summarize the main actions of relaxin, a pleiotropic hormone that was previously suggested to improve acute heart failure and that participates in both metabolism and inflammation regulation at cardiovascular level, and will discuss its potential as future therapeutic target to prevent/reduce cardiovascular diseases.

Inorganic nitrate as a treatment for acute heart failure: a protocol for a single center, randomized, double-blind, placebo-controlled pilot and feasibility study

Background

Acute heart failure (AHF) is a frequent reason for hospitalization worldwide and effective treatment options are limited. It is known that AHF is a condition characterized by impaired vasorelaxation, together with reduced nitric oxide (NO) bioavailability, an endogenous vasodilatory compound. Supplementation of inorganic sodium nitrate (NaNO₃) is an indirect dietary source of NO, through bioconversion. It is proposed that oral sodium nitrate will favorably affect levels of circulating NO precursors (nitrate and nitrite) in AHF patients, resulting in reduced systemic vascular resistance, without significant hypotension.

Methods and outcomes

We propose a single center, randomized, double-blind, placebo-controlled pilot trial, evaluating the feasibility of sodium nitrate as a treatment for AHF. The primary hypothesis that sodium nitrate treatment will result in increased systemic levels of nitric oxide pre-cursors (nitrate and nitrite) in plasma, in parallel with improved vasorelaxation, as assessed by non-invasively derived systemic vascular resistance index. Additional surrogate measures relevant to the known pathophysiology of AHF will be obtained in order to assess clinical effect on dyspnea and renal function.

Discussion

The results of this study will provide evidence of the feasibility of this novel approach and will be of interest to the heart failure community. This trial may inform a larger study.

Effects of serelaxin on the outcome of patients with or without substantial peripheral edema: A subgroup analysis from the RELAX-AHF trial

BACKGROUND

Acute heart failure (AHF) is a heterogeneous disorder, with most of the patients presenting with breathlessness along with varying degrees of peripheral edema. The presence of peripheral edema suggests that volume overload is the cause of decompensation leading to AHF, whereas breathlessness in the absence of edema may reflect a "vascular phenotype." This analysis investigated the characteristics, therapeutic response, and outcome of patients with AHF, with and without overt peripheral edema in the RELAX-AHF trial.

METHODS

Physician-assessed edema scores at baseline were used to categorize the population into those with no/mild edema (score 0 or 1+) and moderate/severe edema (score 2+ or 3+). The effect of serelaxin vs placebo was assessed within each subgroup.

RESULTS

Patients with moderate/severe edema (n = 583; 50.5%) were more likely to have severe dyspnea, orthopnea (>30°), rales (≥1/3), and elevated jugular venous pressure (>6 cm) than the patients with little or no peripheral edema (n=571; 49.5%). The relative benefits of serelaxin in terms of reduction in breathlessness, lower diuretic requirements, decreased length of initial hospital stay and days in intensive care unit/cardiac care unit, and improved prognosis (180-day cardiovascular and all-cause mortality) were generally similar for patients with or without peripheral edema. However, because patients with moderate/severe peripheral edema had worse outcomes, the absolute benefit was generally greater than in patients with no/mild edema.

CONCLUSIONS

Overall, patients with AHF and moderate/severe peripheral edema have a worse prognosis but appear to receive similar relative benefit and perhaps greater absolute benefit from serelaxin administration.

Acute Heart Failure in the Emergency Department: the SAFE-SIMEU Epidemiological Study

BACKGROUND

Patients with acute heart failure (AHF) have high rates of attendance to emergency departments (EDs), with significant health care costs.

OBJECTIVES

We aimed to describe the clinical characteristics of patients attending Italian EDs for AHF and their diagnostic and therapeutic work-up.

METHODS

We carried out a retrospective analysis on 2683 cases observed in six Italian EDs for AHF (January 2011 to June 2012).

RESULTS

The median age of patients was 84 years (interquartile range 12), with females accounting for 55.8% of cases (95% confidence interval [CI] 53.5-57.6%). A first episode of AHF was recorded in 55.3% (95% CI 55.4-57.2%). Respiratory disease was the main precipitating factor (approximately 30% of cases), and multiple comorbidities were recorded in > 50% of cases (history of acute coronary syndrome, chronic obstructive pulmonary disease, diabetes, chronic kidney disease, valvular heart disease). The treatment was based on oxygen (69.7%; 67.9-71.5%), diuretics (69.2%; 67.9-71.5%), nitroglycerin (19.7%; 18.3-21.4%), and noninvasive ventilation (15.2%; 13.8-16.6%). Death occurred within 6 h in 2.5% of cases (2.0-3.1%), 6.4% (5.5-7.3%) were referred to the care of their general practitioners within a few hours from ED attendance or after short-term (< 24 h) observation 13.9% (12.6-15.2%); 60.4% (58.5-62.2%) were admitted to the hospital, and 16.8% (15.4-18.3%) were cared for in intensive care units according to disease severity.

CONCLUSIONS

Our study reporting the "real-world" clinical activity indicates that subjects attending the Italian EDs for AHF are rather different from those reported in international registries. Subjects are older, with a higher proportion of females, and high prevalence of cardiac and noncardiac comorbidities.

How Trialists and Pharmaceutical Sponsors Have Failed Us by Thinking That Acute Heart Failure Is a 48-Hour Illness

Trials of novel therapies for acute heart failure (HF) have followed a convention of short term, most commonly a 48-hour infusion of parenteral therapy compared with placebo or an active drug in a randomized, double-blind study design. Such trials include OPTIME-CHF, SURVIVE, VERITAS, PROTECT, ASCEND-HF, TRUE-HF, and RELAX-AHF-2. This article reviews how this practice in trials began and summarizes the reasons why such a brief exposure of any novel therapy has failed to reduce the end points of rehospitalization or death. Future trials should consider acute and extended use of novel agents to better match the pathophysiology of decompensation and recovery from acute HF.

Expression of RXFP1 Is Decreased in Idiopathic Pulmonary Fibrosis. Implications for Relaxin-based Therapies

RATIONALE

Relaxin is a hormone that has been considered as a potential therapy for patients with fibrotic diseases.

OBJECTIVES

To gauge the potential efficacy of relaxin-based therapies in idiopathic pulmonary fibrosis (IPF), we studied gene expression for relaxin/insulin-like family peptide receptor 1 (RXFP1) in IPF lungs and controls.

METHODS

We analyzed gene expression data obtained from the Lung Tissue Research Consortium and correlated RXFP1 gene expression data with cross-sectional clinical and demographic data. We also employed ex vivo donor and IPF lung fibroblasts to test RXFP1 expression in vitro. We tested CGEN25009, a relaxin-like peptide, in lung fibroblasts and in bleomycin injury.

MEASUREMENTS AND MAIN RESULTS

We found that RXFP1 is significantly decreased in IPF. In patients with IPF, the magnitude of RXFP1 gene expression correlated directly with diffusing capacity of the lung for carbon monoxide (P < 0.0001). Significantly less RXFP1 was detected in vitro in IPF fibroblasts than in donor controls. Transforming growth factor-β decreased RXFP1 in both donor and IPF lung fibroblasts. CGEN25009 was effective at decreasing bleomycin-induced, acid-soluble collagen deposition in vivo. The relaxin-like actions of CGEN25009 were abrogated by RXFP1 silencing in vitro, and, in comparison with donor lung fibroblasts, IPF lung fibroblasts exhibited decreased sensitivity to the relaxin-like effects of CGEN25009.

CONCLUSIONS

IPF is characterized by the loss of RXFP1 expression. RXFP1 expression is directly associated with pulmonary function in patients with IPF. The relaxin-like effects of CGEN25009 in vitro are dependent on expression of RXFP1. Our data suggest that patients with IPF with the highest RXFP1 expression would be predicted to be most sensitive to relaxin-based therapies.

Early Anti-inflammatory and Pro-angiogenic Myocardial Effects of Intravenous Serelaxin Infusion for 72 H in an Experimental Rat Model of Acute Myocardial Infarction

Sprague Dawley rats were subjected to acute myocardial infarction (AMI) by permanent ligation of the left anterior descending coronary artery. At the time of AMI, a subcutaneous mini-osmotic pump was implanted and animals were randomized into three groups, according to the intravenous therapy received during the first 72 h: placebo-treated (saline), serelaxin10-treated (SRLX10 = 10 μg/kg/day), or serelaxin30-treated (SRLX30 = 30 μg/kg/day). Treatment with SRLX30 reduced the expression of inflammatory cytokines and chemokines, as well as the infiltration of macrophages, and increased the expression of pro-angiogenic markers and vessel density in the infarcted myocardium after 7 days. SRLX30 did not reduce early myocardial fibrosis but reduced myocardial levels of sST2 and galectin-3. No significant effects were observed with SRLX10 treatment. A significant correlation was observed between plasma levels of serelaxin and effect measures. The results suggest serelaxin has a protective effect in early processes of cardiac remodeling after AMI.

Cardiovascular Outcomes With Minute Ventilation-Targeted Adaptive Servo-Ventilation Therapy in Heart Failure: The CAT-HF Trial

BACKGROUND

Sleep apnea is common in hospitalized heart failure (HF) patients and is associated with increased morbidity and mortality.

OBJECTIVES

The CAT-HF (Cardiovascular Improvements With MV-ASV Therapy in Heart Failure) trial investigated whether minute ventilation (MV) adaptive servo-ventilation (ASV) improved cardiovascular outcomes in hospitalized HF patients with moderate-to-severe sleep apnea.

METHODS

Eligible patients hospitalized with HF and moderate-to-severe sleep apnea were randomized to ASV plus optimized medical therapy (OMT) or OMT alone (control). The primary endpoint was a composite global rank score (hierarchy of death, cardiovascular hospitalizations, and percent changes in 6-min walk distance) at 6 months.

RESULTS

126 of 215 planned patients were randomized; enrollment was stopped early following release of the SERVE-HF (Adaptive Servo-Ventilation for Central Sleep Apnea in Systolic Heart Failure) trial results. Average device usage was 2.7 h/night. Mean number of events measured by the apnea-hypopnea index decreased from 35.7/h to 2.1/h at 6 months in the ASV group versus 35.1/h to 19.0/h in the control group (p < 0.0001). The primary endpoint did not differ significantly between the ASV and control groups (p = 0.92 Wilcoxon). Changes in composite endpoint components were not significantly different between ASV and control. There was no significant interaction between treatment and ejection fraction (p = 0.10 Cox model); however, pre-specified subgroup analysis suggested a positive effect of ASV in patients with HF with preserved ejection fraction (p = 0.036).

CONCLUSIONS

In hospitalized HF patients with moderate-to-severe sleep apnea, adding ASV to OMT did not improve 6-month cardiovascular outcomes. Study power was limited for detection of safety signals and identifying differential effects of ASV in patients with HF with preserved ejection fraction, but additional studies are warranted in this population. (Cardiovascular Improvements With MV ASV Therapy in Heart Failure [CAT-HF]; NCT01953874).