Effect of neprilysin inhibition on renal function in patients with type 2 diabetes and chronic heart failure who are receiving target doses of inhibitors of the renin-angiotensin system: a secondary analysis of the PARADIGM-HF trial

Chronic Kidney Disease: Strategies to Retard Progression

Chronic kidney disease (CKD), defined as the presence of irreversible structural or functional kidney damages, increases the risk of poor outcomes due to its association with multiple complications, including altered mineral metabolism, anemia, metabolic acidosis, and increased cardiovascular events. The mainstay of treatments for CKD lies in the prevention of the development and progression of CKD as well as its complications. Due to the heterogeneous origins and the uncertainty in the pathogenesis of CKD, efficacious therapies for CKD remain challenging. In this review, we focus on the following four themes: first, a summary of the known factors that contribute to CKD development and progression, with an emphasis on avoiding acute kidney injury (AKI); second, an etiology-based treatment strategy for retarding CKD, including the approaches for the common and under-recognized ones; and third, the recommended approaches for ameliorating CKD complications, and the final section discusses the novel agents for counteracting CKD progression.

Sacubitril/valsartan in chronic kidney disease: From pharmacological mechanism to clinical application

Chronic kidney disease (CKD) is an irreversible, progressive disease characterized by persistent kidney damage, and significantly increased risks of cardiovascular event. However, therapeutic strategies to prevent or slow the progression of CKD remain limited. Sacubitril/valsartan (LCZ696), the representative of the first novel angiotensin receptor-neprilysin inhibitor, has been incorporated into clinical practice guidelines for improving outcomes as a milestone in patients with heart failure. Considering the complex and close relationship between CKD and heart failure, LCZ696 may be beneficial in the treatment of CKD. This review summarizes the pharmacological mechanism and clinical application of LCZ696 in patients with CKD, including its effect on cardiovascular risk and renal outcome, together with potential adverse events. Additionally, due to the influence of serum creatinine and estimated glomerular filtration rate on LCZ696 in patients with heart failure, we also discussed the effects of LCZ696 in patients with advanced CKD and end-stage renal disease. It should be noted that, current clinical studies on LCZ696 are mostly carried out in patients with heart failure, and renal indicators are selected as secondary outcomes. Therefore, more researches should be conducted in patients with CKD alone in the future, to determine the efficacy and safety of LCZ696 in patients with CKD.

Diagnosis and Management of Heart Failure in Elderly Patients from Hospital Admission to Discharge: Position Paper

Multidisciplinary management of worsening heart failure (HF) in the elderly improves survival. To ensure patients have access to adequate care, the current HF and French health authority guidelines advise establishing a clearly defined HF patient pathway. This pathway involves coordinating multiple disciplines to manage decompensating HF. Yet, recent registry data indicate that insufficient numbers of patients receive specialised cardiology care, which increases the risk of rehospitalisation and mortality. The patient pathway in France involves three key stages: presentation with decompensated HF, stabilisation within a hospital setting and transitional care back out into the community. In each of these three phases, HF diagnosis, severity and precipitating factors need to be promptly identified and managed. This is particularly pertinent in older, frail patients who may present with atypical symptoms or coexisting comorbidities and for whom geriatric evaluation may be needed or specific geriatric syndrome management implemented. In the transition phase, multi-professional post-discharge management must be coordinated with community health care professionals. When the patient is discharged, HF medication must be optimised, and patients educated about self-care and monitoring symptoms. This review provides practical guidance to clinicians managing worsening HF in the elderly.

ANMCO POSITION PAPER: on administration of type 2 sodium-glucose co-transporter inhibitors to prevent heart failure in diabetic patients and to treat heart failure patients with and without diabetes

This ANMCO (Associazione Nazionale Medici Cardiologi Ospedalieri) position paper aims to analyse the complex action of sodium-glucose co-transporter 2 inhibitors at the level of the kidney and cardiovascular system, focusing on the effect that these molecules have shown in the prevention and treatment of heart failure in diabetic and non-diabetic subjects. The goal was pursued by comparing the data generated with pathophysiology studies and with multicentre controlled studies in large populations. In accordance with the analysis carried out in the document, the following recommendations are issued: (i) canagliflozin, dapagliflozin, empagliflozin, and ertugliflozin are molecules recommended for the prevention of heart failure hospitalizations in type 2 diabetic subjects; (ii) canagliflozin and dapagliflozin are recommended for the prevention of heart failure hospitalizations in type 2 diabetic subjects with severe chronic kidney disease, dapagliflozin proved to be safe and effective also in diabetic subjects; and (iii) dapagliflozin and empagliflozin are recommended to reduce the combined risk of heart failure and cardiovascular death in diabetic and non-diabetic subjects with heart failure and reduced ejection fraction.

Impact of Sacubitril/Valsartan on Right Heart Failure

Sacubitril/valsartan improves mortality and morbidity in patients with heart failure with reduced ejection fraction. However, its impact on right heart failure remains unknown. We experienced a 70-year-old man who was started on sacubitril/valsartan to treat his right heart failure with moderate tricuspid regurgitation. Following the 3-month sacubitril/valsartan treatment, a functional and geological improvement was observed in the right heart as well as amelioration of his congestive symptoms. Sacubitril/valsartan might improve right heart failure in addition to conventionally-proven left heart failure. Further large-scale studies are warranted to validate our findings.

Renal protective effects and mechanisms of the angiotensin receptor-neprilysin inhibitor LCZ696 in mice with cardiorenal syndrome

AIMS

This study investigated the renal protective effects and mechanisms of angiotensin receptor-neprilysin inhibitor LCZ696 in mice with cardiorenal syndrome.

MATERIALS AND METHODS

Mice were divided into abdominal aortic ligation alone, or treatment with LCZ696 or valsartan, whilst those undergoing sham surgery served as controls. Rat proximal renal tubular epithelial cells from the NRK-52E line were treated with control solution, LCZ696 or valsartan, in the presence or absence of Ang II for 24 h.

KEY FINDINGS

Compared to controls, abdominal aortic ligation significantly increased plasma NT-proBNP and urine neutrophil gelatinase-associated lipocalin (NGAL), which were associated with reduced renal length and velocity time integral on ultrasonography. Histology revealed wrinkling of the glomerular capillary wall and sclerosis of the glomerulus, dilatation of the Bowman's capsule, accompanied by diffuse renal tubular atrophy and fibrosis, accompanied by lower kidney index and higher percentage area of fibrosis. Increases in NGAL and decreased ANP protein and mRNA expression levels were observed. These abnormalities were significantly prevented by LCZ696 and to a lesser extent by valsartan. Cellular experiments demonstrated a central role of Ang II/transforming growth factor-β1/Smad2/3/connective tissue growth factor-dependent signaling leading to type IV collagen deposition. This upregulation was reversed by LCZ696 in a greater extent than valsartan treatment alone, accompanied by a significant improvement in NGAL.

SIGNIFICANCE

LCZ696 can reduce kidney injury to a level beyond valsartan therapy alone in mice with cardiorenal syndrome, which can be speculated by effects on epithelial-mesenchymal transition and fibrosis through downregulating the TGF-β1/Smad2/3/CTGF/Collagen IV pathway.

The evolution and future of diabetic kidney disease research: a bibliometric analysis

BACKGROUND

Diabetic kidney disease (DKD) is one of the most important complications of diabetic mellitus. It is essential for nephrologists to understand the evolution and development trends of DKD.

METHODS

Based on the total cited numbers in the Web of Science Core Collection, which was searched through September 28th, 2020, we performed a bibliometric analysis of the top 100 most cited full-length original articles on the subject of DKD. The timespans, authors, contributions, subcategories, and topics of those 100 articles were analysed. In addition, the evolution of topics in DKD research was investigated.

RESULTS

There were 23,968 items under the subject of DKD in the Web of Science Core Collection. The top 100 cited articles, published from 1999 to 2017, were cited 38,855 times in total. Researchers from the USA contributed the most publications. The number of articles included in 'Experimental studies (EG)', 'Clinical studies (CS)', 'Epidemiological studies (ES)', and 'Pathological and pathophysiological studies (PP)' were 65, 26, 7, and 2, respectively. Among the 15 topics, the most popular topic is the renin-angiotensin-aldosterone system (RAAS), occurring in 26 articles, including 6 of the top 10 most cited articles. The evolution of topics reveals that the role of RAAS inhibitor is a continuous hotspot, and sodium-glucose cotransporter 2 (SGLT-2) inhibitor and glucagon-like peptide 1 (GLP-1) agonist are two renoprotective agents which represent novel therapeutic methods in DKD. In addition, the 26 clinical studies among the top 100 most cited articles were highlighted, as they help guide clinical practice to better serve patients.

CONCLUSIONS

This bibliometric analysis of the top 100 most cited articles revealed important studies, popular topics, and trends in DKD research to assist researchers in further understanding the subject.

Rationale for and Practical Use of Sacubitril/Valsartan in the Patient's Journey with Heart Failure and Reduced Ejection Fraction

Sacubitril with valsartan (sacubitril/valsartan) is a relatively novel compound that has become a milestone in the treatment of patients with chronic heart failure (HF) with reduced ejection fraction (HFrEF) in the last decade. Contemporary data suggest that sacubitril/valsartan is associated with improved outcomes compared with angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, and has a greater beneficial effect on myocardial reverse remodelling. Additionally, two recent trials have shown that sacubitril/valsartan is well-tolerated even in the acute HF setting, thus enabling a continuum of use in the patient's journey with HFrEF. This article summarises available data on the effectiveness and tolerability of sacubitril/valsartan in patients with HFrEF, and provides the clinician with practical insights to facilitate the use of this drug in every setting, with an emphasis on acute HF, hypotension, electrolyte imbalance and renal insufficiency.

Renal protection in chronic heart failure: focus on sacubitril/valsartan

Chronic kidney disease (CKD) is highly prevalent in patients with chronic heart failure (CHF) and increases the risk of overall and cardiovascular (CV) mortality. Despite evidence supporting the effectiveness of angiotensin-converting enzyme inhibitors (ACE-Is), angiotensin receptor blockers, and mineralocorticoid receptor antagonists in decreasing mortality in patients with CHF, CKD hampers the optimization of standard pharmacologic therapy for heart failure. Therefore, other treatment options are needed to optimize treatment outcomes in CHF patients with CKD. The first-in-class angiotensin receptor-neprilysin inhibitor, sacubitril/valsartan, has a complementary activity that counteracts the potential unwanted long-term effects of over-activation of the renin–angiotensin–aldosterone system. Sacubitril/valsartan reduced the risk of CV mortality compared to standard therapy with an ACE-I in patients with heart failure with reduced ejection fraction (HFrEF) in the PARADIGM-HF trial and has been shown to be safe and effective in a broad range of HFrEF patients. However, data on the efficacy and tolerability of sacubitril/valsartan in patients with more advanced CKD are limited. This review discusses the evidence for the role of sacubitril/valsartan in providing additional renal benefit in patients with HFrEF. Data from clinical trials and real-world experience in patients with HFrEF and advanced CKD support the benefits of dual angiotensin/neprilysin inhibition across the breadth of kidney disease stages, including patients with significant renal impairment that was not reported in the pivotal PARADIGM-HF trial, and suggests a central role for the cardiac benefits of sacubitril/valsartan in nephroprotection.

Angiotensin-neprilysin inhibition confers renoprotection in rats with diabetes and hypertension by limiting podocyte injury

OBJECTIVES

Combined angiotensin receptor--neprilysin inhibition (ARNI) reduces glomerulosclerosis better than single angiotensin receptor blockade (ARB) in diabetic, hypertensive rats. The renoprotective mechanism remains unknown, but may depend on superior blood pressure control, improved renal hemodynamics, suppressed renal inflammation or prevention of podocyte loss.

METHODS

To address this, TGR(mREN2)27 rats (a model of angiotensin II-dependent hypertension) were made diabetic for 12 weeks and treated with vehicle (n = 10), valsartan (ARB; n = 7) or sacubitril/valsartan (ARNI; n = 8) for the final 3 weeks. Arterial pressure was measured via radiotelemetry.

RESULTS

Sacubitril/valsartan lowered mean arterial pressure by -50 ± 4 mmHg and valsartan by -43 ± 4 mmHg (P = 0.3). Both treatments lowered albuminuria, but only sacubitril/valsartan maintained high urinary atrial natriuretic peptide, improved glycemic control and protected podocyte integrity, reflected by increased nephrin expression and suppression of transient receptor potential canonical 6 and regulator of calcineurin 1. This resulted in markedly reduced glomerulosclerosis (P < 0.05 vs. control and valsartan). Despite higher effective renal plasma flow and glomerular filtration rates, sacubitril/valsartan did neither improve filtration fraction nor renal immune cell infiltration.

CONCLUSION

Sacubitril/valsartan offers drug-class-specific renoprotection in a preclinical model of diabetes and hypertension. Renoprotection is unrelated to antihypertensive efficacy, renal hemodynamics or inflammation, but may be related to protective effects of natriuretic peptides on podocyte integrity.

Angiotensin receptor/neprilysin inhibitor-a breakthrough in chronic heart failure therapy: summary of subanalysis on PARADIGM-HF trial findings

It is over 4 years since the Prospective Comparison of angiotensin receptor/neprilysin inhibitor (ARNI) with ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial was published in New England Journal of Medicine. The PARADIGM-HF trial was the one that contributed to the official approval to use ARNI simultaneously with cardiac resynchronisation therapy (CRT) or implantable cardioverter-defibrillator (ICD) in patients who receive optimal medical treatment and still presented NYHA II-IV class symptoms according to the 2016 European Society of Cardiology Guidelines for the diagnosis and treatment of acute and chronic heart failure. The aim of this article is to summarise current knowledge on the activity of ARNI in a selected group of patients with heart failure with reduced ejection fraction (HFrEF) based on a recent PARADIGM-HF subanalysis in the field of renal function in patients with and without chronic kidney disease, glycaemia control in patients with diabetes, ventricular arrhythmias and sudden cardiac death and health-related quality of life. This article includes also recently announced findings on the TRANSITION study which revealed that HFrEF therapy with ARNI might be safely initiated after an acute decompensated heart failure episode, including patients with heart failure de novo and ACEI/ARB naïve, both hospitalised or shortly after discharge, in contrary to the PARADIGM-HF trial, where patients had to be administered a stable dose of an ACEI/ARB equivalent to enalapril 10 mg a day for at least 4 weeks before the screening.

The effect of neprilysin and renin inhibition on the renal dysfunction following ischemia-reperfusion injury in the rat

The natriuretic peptide (NP) system counter-regulates the renin-angiotensin system (RAS), so enhancing the activity of natriuretic peptides (NPs) may be beneficial in conditions when RAS is activated such as ischemia-reperfusion injury (IRI). Neprilysin is the key enzyme responsible for the degradation of NPs. The effects of neprilysin inhibition or the combination of neprilysin inhibition and RAS inhibition on renal IRI-induced renal dysfunction have not been investigated yet. To investigate this, rats underwent sham surgery or bilateral IRI for 20 min. G-Als, G-Scb, and G-Als+Scb underwent similar protocol but received aliskiren (renin inhibitor), sacubitril (neprilysin inhibitor) or a combination of both pre- and post-IRI, respectively. IRI caused significant alterations in all renal functional parameters, markers of acute renal injury, pro-inflammatory and pro-fibrotic cytokines, and histological features. All these alterations were significantly attenuated in G-Als, G-Scb, and G-Als+Scb. The attenuations in the alterations in serum creatinine, creatinine clearance, and histological features were larger in G-Als+Scb compared to either G-Als or G-Scb. We conclude that RAS blockade by a renin inhibitor (aliskiren) or neprilysin inhibition by sacubitril separately led to significant attenuation in the renal IRI-induced renal dysfunction. The combination of aliskiren and sacubitril was more effective than either one alone.

Renal protective effect of sacubitril/valsartan in patients with heart failure

Sacubitril/valsartan is a combined neprilysin inhibitor/angiotensin II receptor blocker designed for treatment of heart failure (HF). Nonetheless, its renal protective effect remained an issue of debate. This retrospective cohort study investigated the renal protective effect of sacubitril/valsartan in HF patients. HF patients on sacubitril/valsartan or valsartan for > 30 days were matched for gender, age, estimated glomerular filtration rate (eGFR), and left ventricular ejection fraction (LVEF) to be enrolled into analysis. The follow-up period was 18 months. The outcomes included end eGFR, renal function decline defined as 20% reduction of eGFR, mortality, and HF-related hospitalization. Each group had 137 patients after matching. The mean age was 72.7 years and 65.7% were male. Mean eGFR was 70.9 mL/min/1.73 m² and LVEF was 54.0% at baseline. Overall, the eGFR of sacubitril/valsartan groups was significantly higher than valsartan group at the end (P < 0.01). Subgroup analysis showed that the difference in eGFR was significant in subgroups with LVEF ≥ 40% or eGFR ≥ 60 mL/min/1.73 m². Multivariate Cox regression model showed that sacubitril/valsartan group had significantly reduced risk for renal function decline (hazard ratio: 0.5, 95% confidence interval: 0.3–0.9). Kaplan–Meier curve showed no difference in the risk for cardiovascular mortality, all-cause mortality or HF-related hospitalization. We showed renal protective effect of neprilysin inhibition in HF patients and specified that subgroups with LVEF ≥ 40% or eGFR ≥ 60 mL/min/1.73 m² were sensitive to this effect, suggesting an optimal subgroup of this treatment.

Renal Outcomes in Patients with Systolic Heart Failure Treated With Sacubitril-Valsartan or Angiotensin Converting Enzyme Inhibitor/Angiotensin Receptor Blocker

Objective

To assess 4 adverse renal outcomes in a heterogeneous cohort of patients with systolic heart failure (HF) who were prescribed sacubitril-valsartan vs angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACEi/ARB).

Patients and Methods

The OptumLabs Database Warehouse, which contains linked administrative claims and laboratory results, was used to identify patients with systolic HF who were prescribed sacubitril-valsartan or ACEi/ARB between July 1, 2015, and September 30, 2019. One-to-one propensity score matching and inverse probability of treatment weighting was used to balance baseline variables. Cox proportional hazards modeling was performed to compare renal outcomes in both medication groups, including 30% or more decline in estimated glomerular filtration rate (eGFR), doubling of serum creatinine, acute kidney injury (AKI), and kidney failure (eGFR < 15 mL/min per 1.73 m², kidney transplant, or dialysis initiation).

Results

A total of 4667 matched pairs receiving sacubitril-valsartan or ACEi/ARB were included; the mean follow-up period was 7.8±7.8 months. The mean age was 69.4±11 years; 35% were female, 19% black, and 15% Hispanic. The cumulative risk at 1 year was 6% for 30% or more decline in eGFR, 2% for doubling of serum creatinine, 3% for AKI, and 2% to 3% for kidney failure. Furthermore, no significant differences in risk were observed with sacubitril-valsartan compared with ACEi/ARB for a 30% or more decline in eGFR (hazard ratio [HR], 0.96; 95% CI, 0.79 to 1.10), doubling of serum creatinine (HR, 0.94; 95% CI, 0.69 to 1.27); AKI (HR, 0.80; 95% CI, 0.63 to 1.03), and kidney failure (HR 0.80; 95% CI, 0.59 to 1.08).

Conclusion

Among patients with systolic HF, the risk of adverse renal outcomes was similar between patients prescribed sacubitril-valsartan and those prescribed ACEi/ARB.

Novelties in Therapy of Chronic Heart Failure

In recent decades, considerable advances have been made in the treatment of heart failure. The main target of heart failure therapy is the inhibition of the sympathetic nervous system and renin-angiotensin-aldosterone system. The angiotensin receptor blockers represent a breakthrough in the treatment of heart failure with a demonstrated effect on reduction of cardiovascular events. However, new perspectives derive from latest drugs developed for diabetes, iron deficiency, and hyperkalemia. New frontiers are also opened to the development of neurohormonal therapies, antagonists of inflammatory mediators, inotropic agents, and cell-based treatments.

Inhibition of neprilysin with sacubitril without RAS blockage aggravates renal disease in Dahl SS rats

Salt-sensitive (SS) hypertension is accompanied with severe cardiorenal complications. In this condition, elevated blood pressure (BP) resulting from salt retention is associated with counterintuitively lower levels of atrial natriuretic peptide (ANP). In plasma, ANP is degraded by the neprilysin; therefore, pharmacological inhibition of this metalloprotease (i.e., with sacubitril) can be employed to increase ANP level. We have shown earlier that sacubitril in combination with valsartan (75 μg/day each) had beneficial effects on renal function in Dahl SS rats. The goal of this study was to evaluate the effects of a higher dose of sacubitril on renal damage in this model. To induce hypertension, male Dahl SS rats were fed a 4% NaCl diet (HS) for 21 days, and were administered sacubitril (125 μg/day) or vehicle via s.c. osmotic pumps. At the end of the HS challenge, both groups exhibited similar outcomes for GFR, heart weight, plasma electrolytes, BUN, and creatinine. Sacubitril exacerbated kidney hypertrophy, but did not affect levels of renal fibrosis. We also observed aggravated glomerular lesions and increased formation of protein casts in the sacubitril-treated animals compared to controls. Thus, in Dahl SS rats, administration of sacubitril without renin-angiotensin-system blockage had adverse effects on renal disease progression, particularly in regards to glomerular damage and protein cast formation. We can speculate that while ANP levels are increased because of neprilysin inhibition, there are off-target effects of sacubitril, which are detrimental to renal function in the SS hypertensive state.

How Diabetes and Heart Failure Modulate Each Other and Condition Management

Heart failure (HF) and diabetes mellitus (DM) confer considerable burden on the health care system. Although these often occur together, DM can increase risk of HF, whereas HF can accelerate complications of DM. HF is a clinical syndrome resulting from systolic or diastolic impairment caused by ischemic, nonischemic (eg, DM), or other etiologies. HF exists along a spectrum from stage A (ie, persons at risk of DM) to stage D (ie, refractory HF from end-stage DM cardiomyopathy [DMCM]). HF is further categorized by reduced, midrange, and preserved ejection fraction (EF). In type 2 DM, the most prevalent form of DM, several pathophysiological mechanisms (eg, insulin resistance and hyperglycemia) can contribute to myocardial damage, leading to DMCM. Management of HF and DM and patient outcomes are guided by EF and drug efficacy. In this review, we focus on the interplay between HF and DM on disease pathophysiology, management, and patient outcomes. Specifically, we highlight the role of novel antihyperglycemic (eg, sodium glucose cotransporter 2 inhibitors) and HF therapies (eg, renin-angiotensin-aldosterone system inhibitors) on HF outcomes in patients with DM and HF.

Effect of sacubitril/valsartan on renal function: a systematic review and meta-analysis of randomized controlled trials

A worsening renal function is prevalent among patients with cardiovascular disease, especially heart failure (HF). Sacubitril/valsartan appears to prevent worsening of renal function and progression of chronic kidney disease (CKD) as compared with renin-angiotensin system (RAS) inhibitors alone in HF patients. It is unclear whether these advantages are present in HF patients only, or can be extended to other categories of patients, in which this drug was studied. We performed a systematic review and meta-analysis to assess the consistency of effect size regarding renal outcome across randomized controlled trials (RCTs) that compared sacubitril/valsartan with RAS inhibitors in patients with or without HF. We searched Medline (PubMed), Scopus, and Thomson Reuters Web of Science databases until June 2020. We took into account RCTs that compared sacubitril/valsartan with a RAS inhibitor and reported data regarding renal function. We used random-effects models to obtain summary odds ratio (OR) with 95% confidence interval (CI). We extracted hazard ratios for renal outcomes, glomerular filtration rate slopes or rates of renal adverse events. Sensitivity analyses were performed by moderator analysis and random-effects meta-regression. The search revealed 10 RCTs (published between 2012 and 2019) on 16 456 subjects. Sacubitril/valsartan resulted in a lower risk of renal dysfunction as compared with RAS inhibitors alone [k = 10; pooled OR = 0.70 (95% CI 0.57-0.85); P < 0.001], with a moderate inconsistency between studies [Q(9) = 15.18; P = 0.086; I2  = 40.73%]. A stronger association was found in studies including older patients (k = 10; β = -0.047730; P = 0.020) or HF patients with preserved ejection fraction [pooled OR = 0.53 (0.41-0.68) vs. 0.76 (0.57-1.01) for studies on HF patients with reduced ejection fraction; P for comparison = 0.065]. The effect size did not change with different comparators (angiotensin-converting enzyme inhibitors vs. angiotensin II type 1 receptor blockers, P = 0.279). No significant association was found when the analysis was restricted to studies on non-HF patients [k = 3; pooled OR = 0.86 (0.61-1.22); P = 0.403] and studies with high risk of bias [k = 3; pooled OR = 0.34 (0.08-1.44); P = 0.143]. Our findings support the role of sacubitril/valsartan on preservation of renal function, especially in older patients and HF patients with preserved ejection fraction. However, evidence is currently limited to HF patients, while the renal outcome of sacubitril/valsartan therapy outside the HF setting needs to be further investigated.

Cardiovascular and Renal Outcomes of Mineralocorticoid Receptor Antagonist Use in PARAGON-HF

OBJECTIVES

This study sought to evaluate the efficacy and safety of sacubitril/valsartan in patients with heart failure with preserved ejection fraction (HFpEF) according to background mineralocorticoid receptor antagonist (MRA) therapy.

BACKGROUND

Current guidelines recommend consideration of MRAs in selected patients with HFpEF. This study assessed cardiovascular outcomes, renal outcomes, and safety of sacubitril/valsartan compared with valsartan in patients with HFpEF according to background MRA treatment.

METHODS

PARAGON-HF (Prospective Comparison of ARNI [angiotensin receptor-neprilysin inhibitor] with ARB [angiotensin-receptor blockers] Global Outcomes in HF with Preserved Ejection Fraction) randomized 4,796 patients with HFpEF to sacubitril/valsartan or valsartan. In a pre-specified subgroup analysis, the effect of sacubitril/valsartan versus valsartan was evaluated according to baseline MRA use on the primary study composite of total heart failure hospitalizations and cardiovascular death using semiparametric proportional rates methods, as well as the renal composite of ≥50% decrease in estimated glomerular filtration rate, development of end-stage renal disease, or death from renal causes using Cox proportional hazards regression models. Annual decline in estimated glomerular filtration rate was analyzed with repeated-measures mixed-effect models. Key safety outcomes included incidence of hypotension, hyperkalemia, and elevations in serum creatinine above predefined thresholds.

RESULTS

Patients treated with MRAs at baseline (n = 1,239, 26%), compared with MRA nonusers (n = 3,557, 74%), were younger (72 vs. 73 years), more often male (52% vs. 47%), had lower left ventricular ejection fraction (57% vs. 58%), and a higher proportion of prior HF hospitalization (59% vs. 44%) (all p < 0.001). Efficacy of sacubitril/valsartan compared with valsartan with regard to the primary cardiovascular (for MRA users: rate ratio: 0.73; 95% confidence interval [CI]: 0.56 to 0.95; vs. for MRA nonusers: rate ratio: 0.94; 95% CI: 0.79 to 1.11; p_interaction = 0.11) and renal endpoints (for MRA users: hazard ratio: 0.31; 95% CI: 0.13 to 0.76; vs. for MRA non-users: HR: 0.59; 95% CI: 0.36 to 0.95; p_interaction = 0.21) did not significantly vary by baseline MRA use. The incidence of key safety outcomes including hypotension and severe hyperkalemia (K > 6.0 mmol/l) did not vary by baseline MRA use. However, annual decline in estimated glomerular filtration rate was less with the combination of MRA and sacubitril/valsartan (for MRA users: absolute difference favoring sacubitril/valsartan: +1.2 ml/min/1.73 m² per year; 95% CI: 0.6 to 1.7; vs. for MRA nonusers: +0.4; 95% CI: 0.1 to 0.7; p_interaction = 0.01).

CONCLUSIONS

Clinical efficacy of sacubitril/valsartan compared with valsartan with regard to predefined cardiorenal composite outcomes in PARAGON-HF was consistent in patients treated and not treated with MRA at baseline. Addition of sacubitril/valsartan rather than valsartan alone to MRA appears to be associated with a lesser decline in renal function and no increase in severe hyperkalemia. These data support possible added value of combination treatment with sacubitril/valsartan and MRA in patients with HFpEF. (Prospective Comparison of ARNI [angiotensin receptor -neprilysin inhibitor] with ARB [angiotensin-receptor blockers] Global Outcomes in HF with Preserved Ejection Fraction [PARAGON-HF]; NCT01920711).

Association of Sacubitril/Valsartan with Metabolic Parameters in Patients with Reduced Ejection Fraction Heart Failure at a Multidisciplinary Clinic

Background: Sacubitril/valsartan was approved for New York Heart Association (NYHA) class II-IV heart failure with reduced ejection fraction (HFrEF) in 2015, based on the results of the PARADIGM-HF trial, which showed a reduction in cardiovascular (CV) death and heart failure hospitalization, compared with enalapril. A subsequent subgroup analysis of the trial showed glycemic improvement for patients on sacubitril/valsartan compared with those on enalapril. Methods: This was a retrospective observational study at the Loma Linda University (LLU) International Heart Institute (IHI). The aim was to evaluate the association of sacubitril/valsartan with glycemic index and other metabolic parameters, including change in hemoglobin A1C (HbA1C), blood pressure (BP), ejection fraction (EF), body weight, and lipid profile from baseline and at 3, 6, and 12 months. The rates of CV-related hospitalizations and total hospitalizations were also assessed. Results: The change in mean HbA1C from baseline was not significantly different at 1 year (P = 0.993). The mean EF was significantly higher and the mean diastolic BP was significantly lowered. Body weight and lipid parameters remained unchanged. Both the rates of CV-related hospitalizations and total hospitalizations were significantly lowered. For the prespecified subgroup analysis of diabetic HFrEF patients, the mean HbA1C was nonsignificant at 12 months (mean difference -0.48, P = 0.993). Conclusion: A non-significant reduction in HbA1C was associated in HFrEF patients with diabetes mellitus. Large randomized trials are needed to confirm our findings regarding the potential metabolic benefits of sacubitril/valsartan.

Chronic kidney disease, heart failure and neprilysin inhibition

Patients with chronic kidney disease are at increased risk of cardiovascular disease and this often manifests clinically like heart failure. Conversely, patients with heart failure frequently have reduced kidney function. The links between the kidneys and cardiovascular system are being elucidated, with blood pressure being a key risk factor. Patients with heart failure have benefitted from many trials which have now established a strong evidence based on which to base management. However, patients with advanced kidney disease have often been excluded from these trials. Nevertheless, there is little evidence that the benefits of such treatments are modified by the presence or absence of kidney disease, but more direct evidence among patients with advanced kidney disease is required. Neprilysin inhibition is the most recent treatment to be shown to improve outcomes among patients with heart failure. The UK HARP-III trial assessed whether neprilysin inhibition improved kidney function in the short- to medium-term and its effects on cardiovascular biomarkers. Although no effect (compared to irbesartan control) was found on kidney function, allocation to neprilysin inhibition (sacubitril/valsartan) did reduce cardiac biomarkers more than irbesartan, suggesting that this treatment might improve cardiovascular outcomes in this population. Larger clinical outcomes trials are needed to test this hypothesis.

Cardiac and Kidney Benefits of Empagliflozin in Heart Failure Across the Spectrum of Kidney Function: Insights From EMPEROR-Reduced

Supplemental Digital Content is available in the text.

In EMPEROR-Reduced (Empagliflozin Outcome Trial in Patients With Chronic Heart Failure With Reduced Ejection Fraction), empagliflozin reduced cardiovascular death or heart failure (HF) hospitalization and total HF hospitalizations, and slowed the progressive decline in kidney function in patients with HF and a reduced ejection fraction, with and without diabetes. We aim to study the effect of empagliflozin on cardiovascular and kidney outcomes across the spectrum of kidney function.

Natriuretic peptides and neprilysin inhibition in hypertension and hypertensive organ damage

The family of natriuretic peptides (NPs) discovered in mammalian tissues including cardiac atrium and brain consists of three members, namely, atrial, B- and C-type natriuretic peptides (ANP, BNP, CNP). Since the discovery, basic and clinical studies have been vigorously performed to explore the biological functions and pathophysiological roles of NPs in a wide range of diseases including hypertension and heart failure. These studies revealed that ANP and BNP are hormones secreted from the heart into the blood stream in response to pre- or after-load, counteracting blood pressure (BP) elevation and fluid retention through specific receptors. Meanwhile, CNP was found to be produced by the vascular endothelium, acting as a local mediator potentially serving protective functions for the blood vessels. Because NPs not only exert blood pressure lowering actions but also alleviate hypertensive organ damage, attempts have been made to develop therapeutic agents for hypertension by utilizing this family of NPs. One strategy is to inhibit neprilysin, an enzyme degrading NPs, thereby enhancing the actions of endogenous peptides. Recently, a dual inhibitor of angiotensin receptor-neprilysin was approved for heart failure, and neprilysin inhibition has also been shown to be beneficial in treating patients with hypertension. This review summarizes the roles of NPs in regulating BP, with special references to hypertension and hypertensive organ damage, and discusses the therapeutic implications of neprilysin inhibition.

Recently Approved and Under Investigation Drugs for Treating Patients with Heart Failure

Heart Failure (HF) represents a leading cause of morbidity and mortality worldwide. Despite the recent advances in the treatment of this condition, patients´ prognosis remains unfavorable in most cases. Sacubitril/valsartan and ivabradine have been recently approved to improve clinical outcomes in patients with HF with reduced ejection fraction. Drugs under investigation for treating patients with HF encompass many novel mechanisms including vasoactive peptides, blocking inflammatory- mediators, natriuretic peptides, selective non-steroidal mineralocorticoid-receptor antagonists, myocardial β3 adrenoreceptor agonists, inhibiting the cytochrome C/cardiolipin peroxidase complex, neuregulin-1/ErbB signaling and inhibiting late inward sodium current. The aim of this manuscript is to review the main drugs under investigation for the treatment of patients with HF and give perspectives for their implementation into clinical practice.

Efficacy and safety of sacubitril-valsartan in heart failure: a meta-analysis of randomized controlled trials

Aims

Sacubitril‐valsartan has been shown to have superior effects over angiotensin‐converting enzyme inhibitors and angiotensin receptor blockers in patients with heart failure (HF) and hypertension. The efficacy and safety of sacubitril‐valsartan in patients with HF are controversial. We performed a meta‐analysis of randomized controlled trials to assess and compare the effect and adverse events of sacubitril‐valsartan, valsartan, and enalapril in patients with HF.

Methods and results

We conducted a systematic search using PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov. Randomized controlled trials involving the use of sacubitril‐valsartan in patients with HF were included. We assessed the pooled odds ratio (OR) of all‐cause mortality, cardiovascular mortality, and hospitalization for HF in fixed‐effects models and the pooled risk ratio (RR) of symptomatic hypotension, worsening renal function, and hyperkalaemia in fixed‐effects models. Of the 315 identified records, six studies involving 14 959 patients were eligible for inclusion. Sacubitril‐valsartan reduced the endpoints of all‐cause mortality and cardiovascular mortality in patients with HF with reduced ejection fraction (HFrEF) in three trials with pooled ORs of 0.83 (P = 0.0006) and 0.78 (P < 0.0001), respectively. Regarding the composite outcome of hospitalization for HF in five trials, the pooled OR was 0.79 (P < 0.00001). Compared with enalapril or valsartan, sacubitril‐valsartan was associated with a high risk of symptomatic hypotension (RR 1.47, P < 0.00001), low risk of worsening renal function (RR 0.81, P = 0.005), and low rate of serious hyperkalaemia (≥6.0 mmol/L) (RR 0.76, P = 0.0007) in all six trials.

Conclusions

Compared with angiotensin‐converting enzyme inhibitors or angiotensin receptor blockers, sacubitril‐valsartan significantly decreased the risk of death from all causes or cardiovascular causes in HFrEF and hospitalization for HF in both patients with HFrEF and HF with preserved ejection fraction. Sacubitril‐valsartan reduced the risk of renal dysfunction and serious hyperkalaemia but was associated with more symptomatic hypotension.

Renal function dynamics following co-administration of sacubitril/valsartan and empagliflozin in patients with heart failure and type 2 diabetes

Aims

The aim of this study was to evaluate the safety profile in terms of changes in renal function after co‐treatment with sacubitril/valsartan and empagliflozin in patients with type 2 diabetes (T2D) and heart failure with reduced ejection fraction (HFrEF).

Methods and results

This multicentre observational analysis included 108 patients with T2D and HFrEF treated with both agents: baseline sacubitril/valsartan (Group A; n = 43), baseline empagliflozin (Group B; n = 42), or both agents initiated simultaneously (Group C; n = 23). The primary endpoint was estimated glomerular filtration rate (eGFR) dynamics across treatment groups. A binary characterization of worsening renal function (WRF)/improved renal function (IRF) was included in the primary endpoint. WRF and IRF were defined as an increase/decrease in serum creatinine ≥ 0.3 mg/dL or GFR ≥ 20%. Changes in quantitative variables were evaluated using joint modelling of survival and longitudinal data (JM). Rates and their treatment differences were determined by Poisson regression. The mean left ventricle ejection fraction and eGFR were 32 ± 6% and 70 ± 28 mL/min/1.73 m², respectively. At a median follow‐up of 1.01 years (inter‐quartile range 0.71–1.50), 377 outpatient visits were recorded. Although there were differences in GFR trajectories over time within each treatment, they did not achieve statistical significance (omnibus P = 0.154). However, when these differences were contrasted among groups, there was a significant decrease in GFR in Group A as compared with Group B (P = 0.002). The contrast between Groups C and B was not significant (P = 0.430). These differences were also reflected when the rates for WRF and IRF were contrasted among treatments.

Conclusions

The co‐administration of sacubitril/valsartan and empagliflozin in patients with HFrEF and concomitant T2D appears to be safe in terms of renal function.

Neprilysin as a Biomarker: Challenges and Opportunities

Neprilysin (NEP) inhibition is a successful novel therapeutic approach in heart failure with reduced ejection fraction. Assessing individual NEP status might be important for gathering insights into mechanisms of disease and optimising individualised patient care. NEP is a zinc-dependent multisubstrate-metabolising oligoendopeptidase localised in the plasma membrane with the catalytic site facing the extracellular space. Although NEP activity in vivo is predominantly tissue-based, NEP can be released into the circulation via ectodomain shedding and exosomes. Attempts to determine circulating NEP concentrations and activity have not yet resulted in convincingly coherent results relating NEP biomarkers to heart failure disease severity or outcomes. NEP is naturally expressed on neutrophils, opening up the possibility of measuring a membrane-associated form with integrity. Small studies have linked NEP expression on neutrophils with inflammatory state and initial data might indicate its role in heart failure with reduced ejection fraction. Future studies need to assess the regulation of systemic NEP activity, which is assumed to be tissue-based, and the relationship of NEP activation with disease state. The relationship between tissue NEP activity and easily accessible circulating NEP biomarkers and the impact of the latter remains to be established.

Characterization of the inflammatory-metabolic phenotype of heart failure with a preserved ejection fraction: a hypothesis to explain influence of sex on the evolution and potential treatment of the disease

Accumulating evidence points to the existence of an inflammatory-metabolic phenotype of heart failure with a preserved ejection fraction (HFpEF), which is characterized by biomarkers of inflammation, an expanded epicardial adipose tissue mass, microvascular endothelial dysfunction, normal-to-mildly increased left ventricular volumes and systolic blood pressures, and possibly, altered activity of adipocyte-associated inflammatory mediators. A broad range of adipogenic metabolic and systemic inflammatory disorders - e.g. obesity, diabetes and metabolic syndrome as well as rheumatoid arthritis and psoriasis - can cause this phenotype, independent of the presence of large vessel coronary artery disease. Interestingly, when compared with men, women are both at greater risk of and may suffer greater cardiac consequences from these systemic inflammatory and metabolic disorders. Women show disproportionate increases in left ventricular filling pressures following increases in central blood volume and have greater arterial stiffness than men. Additionally, they are particularly predisposed to epicardial and intramyocardial fat expansion and imbalances in adipocyte-associated proinflammatory mediators. The hormonal interrelationships seen in inflammatory-metabolic phenotype may explain why mineralocorticoid receptor antagonists and neprilysin inhibitors may be more effective in women than in men with HFpEF. Recognition of the inflammatory-metabolic phenotype may improve an understanding of the pathogenesis of HFpEF and enhance the ability to design clinical trials of interventions in this heterogeneous syndrome.

The role of sacubitril/valsartan in the treatment of chronic heart failure with reduced ejection fraction in hypertensive patients with comorbidities: From clinical trials to real-world settings

Background:

Sacubitril/valsartan, the first agent to be approved in a new class of drugs called angiotensin receptor neprilysin inhibitors (ARNIs), has been shown to reduce cardiovascular mortality and morbidity compared to enalapril in outpatient subjects with chronic heart failure (HF) and reduced left ventricular ejection fraction (HFrEF). However, there is little real-world evidence about the efficacy of ARNIs in elderly hypertensive patients with HFrEF and comorbidities.

Methods:

In this prospective open-label study, 108 subjects, 54 of them (mean age 78.6 ± 8.2 years, 75.0 % male), with HFrEF (29.8 ± 4.3 %) and New York Heart Association (NYHA) class II-III symptoms were assigned to receive ARNIs twice daily, according to the recommended dosage of 24/26, 49/51, 97/103 mg. Patients were gender- and age-matched with a control arm of patients with HFrEF receiving the optimal standard therapy for HF. The clinic blood pressure (BP), N-terminal pro-B-type natriuretic peptide (NT-proBNP), estimated glomerular filtration rate (eGFR), blood glucose and glycated hemoglobin (HbA1c), uric acid (UA), left ventricular ejection fraction (LVEF) and NYHA class were evaluated at a mean follow-up of 12 months. During the follow-up, the clinical outcomes, including mortality and re-hospitalization for HF, were collected.

Results:

NYHA class significantly improved in the ARNI arm compared to the control (24.9 vs. 6.4 %, shifting from class III to II, and 55.4 vs. 25.2 %, from class II to I, p < 0.05 for all). A significant improvement in LVEF and eGFR levels was found in the ARNI arm compared to controls (42.4 vs. 34.2 %, 73.8 vs. 61.2 mL/min, respectively; p < 0.001 for all). NT-proBNP, clinic systolic and diastolic BP, blood glucose, HbA1c and UA values were reduced in both treatment arms, but they were lower in the ARNI arm compared controls (3107 vs. 4552 pg/mL, 112.2 vs. 120.4 and 68.8 vs. 75.6 mmHg, 108.4 vs. 112.6 mg/dL, 5.4 vs. 5.9 % and 5.9 vs. 6.4 mg/dL, respectively, p < 0.05). Mortality and re-hospitalization for HF was lower in the ARNI arm than controls (20.1 vs. 33.6 % and 27.7 vs. 46.3 % respectively; p < 0.05 for all). Gender differences were not found in either arm. No patients refused to continue the study, and no side effects to the ARNI treatment were observed.

Conclusions:

In elderly patients with HFrEF and comorbidities, ARNI treatment seems effective and safe. The improvement in LVEF and cardiac remodeling, BP, eGFR, serum glucose, UA and HbA1c could be the mechanisms by which ARNIs play their beneficial role on clinical outcomes. However, these results need to be confirmed in studies involving a greater number of subjects, and with a longer follow-up.

Practical management of worsening renal function in outpatients with heart failure and reduced ejection fraction: Statement from a panel of multidisciplinary experts and the Heart Failure Working Group of the French Society of Cardiology

Renal function is often affected in patients with chronic heart failure with reduced ejection fraction (HFrEF). The complex interplay between heart and renal dysfunction makes renal function and potassium monitoring mandatory. Renin-angiotensin-aldosterone system (RAAS) blockers are a life-saving treatment for patients with HFrEF, regardless of worsening renal function. Uptitration to the maximum-tolerated dose should be a constant goal. This simple fact is all too often forgotten (only 30% of patients with heart failure receive the target dosage of RAAS blockers), and the RAAS blocker effect on renal function is sometimes misunderstood. RAAS blockers are not nephrotoxic drugs as they only have a functional effect on renal function. In many routine clinical cases, RAAS blockers are withheld or stopped because of this misunderstanding, combined with suboptimal assessment of the clinical situation and underestimation of the life-saving effect of RAAS blockers despite worsening renal function. In this expert panel, which includes heart failure specialists, geriatricians and nephrologists, we propose therapeutic management algorithms for worsening renal function for physicians in charge of outpatients with chronic heart failure. Firstly, the essential variables to take into consideration before changing treatment are the presence of concomitant disorders that could alter renal function status (e.g. infection, diarrhoea, hyperthermia), congestion/dehydration status, blood pressure and intake of nephrotoxic drugs. Secondly, physicians are invited to adapt medication according to four clinical scenarios (patient with congestion, dehydration, hypotension or hyperkalaemia). Close biological monitoring after treatment modification is mandatory. We believe that this practical clinically minded management algorithm can help to optimize HFrEF treatment in routine clinical practice.

Change in renal function associated with drug treatment in heart failure: national guidance

Inhibitors of the renin–angiotensin–aldosterone (RAAS) system are cornerstones of the management of patients with heart failure with reduced left ventricular ejection fraction (HFrEF). However, RAAS inhibitors may cause decline in renal function and/or hyperkalaemia, particularly during initiation and titration, intercurrent illness and during worsening of heart failure. There is very little evidence from clinical trials to guide the management of renal dysfunction. The Renal Association and British Society for Heart Failure have collaborated to describe the interactions between heart failure, RAAS inhibitors and renal dysfunction and give clear guidance on the use of RAAS inhibitors in patients with HFrEF. During initiation and titration of RAAS inhibitors, testing renal function is mandatory; a decline in renal function of 30% or more can be acceptable. During intercurrent illness, there is no evidence that stopping RAAS inhibitor is beneficial, but if potassium rises above 6.0 mmol/L, or creatinine rises more than 30%, RAAS inhibitors should be temporarily withheld. In patients with fluid retention, high doses of diuretic are needed and a decline in renal function is not an indication to reduce diuretic dose: if the patient remains congested, more diuretics are required. If a patient is hypovolaemic, diuretics should be stopped or withheld temporarily. Towards end of life, consider stopping RAAS inhibitors. RAAS inhibition has no known prognostic benefit in heart failure with preserved ejection fraction. Efforts should be made to initiate, titrate and maintain patients with HFrEF on RAAS inhibitor treatment, whether during intercurrent illness or worsening heart failure.

Neprilysin: A Potential Therapeutic Target of Arterial Hypertension?

Arterial hypertension is the most prevalent chronic disease in the adult population of developed countries and it constitutes a significant risk factor in the development of cardiovascular disease, contributing to the emergence of many comorbidities, among which heart failure excels, a clinical syndrome that nowadays represents a major health problem with uncountable hospitalizations and the indolent course of which progressively worsens until quality of life decreases and lastly death occurs prematurely. In the light of this growing menace, each day more efforts are invested in the field of cardiovascular pharmacology, searching for new therapeutic options that allow us to modulate the physiological systems that appear among these pathologies. Therefore, in the later years, the study of natriuretic peptides has become so relevant, which mediate beneficial effects at the cardiovascular level such as diuresis, natriuresis, and decreasing cardiac remodeling; their metabolism is mediated by neprilysin, a metalloproteinase, widely expressed in the human and capable of catalyzing many substrates. The modulation of these functions has been studied by decades, giving room to Sacubitril, the first neprilysin inhibitor, which in conjunction with an angiotensin receptor blocker has provided a high efficacy and tolerability among patients with heart failure, for whom it has already been approved and recommended. Nonetheless, in the matter of arterial hypertension, significant findings have arisen that demonstrate the potential role that it will play among the pharmacological alternatives in the upcoming years.

Critical Role of Neprilysin in Kidney Angiotensin Metabolism

RATIONALE

Kidney homeostasis is critically determined by the coordinated activity of the renin-angiotensin system (RAS), including the balanced synthesis of its main effector peptides Ang (angiotensin) II and Ang (1-7). The condition of enzymatic overproduction of Ang II relative to Ang (1-7) is termed RAS dysregulation and leads to cellular signals, which promote hypertension and organ damage, and ultimately progressive kidney failure. ACE2 (angiotensin-converting enzyme 2) and NEP (neprilysin) induce the alternative, and potentially reno-protective axis by enhancing Ang (1-7) production. However, their individual contribution to baseline RAS balance and whether their activities change in chronic kidney disease (CKD) has not yet been elucidated.

OBJECTIVE

To examine whether NEP-mediated Ang (1-7) generation exceeds Ang II formation in the healthy kidney compared with diseased kidney.

METHODS AND RESULTS

In this exploratory study, we used liquid chromatography-tandem mass spectrometry to measure Ang II and Ang (1-7) synthesis rates of ACE, chymase and NEP, ACE2, PEP (prolyl-endopeptidase), PCP (prolyl-carboxypeptidase) in kidney biopsy homogenates in 11 healthy living kidney donors, and 12 patients with CKD. The spatial expression of RAS enzymes was determined by immunohistochemistry. Healthy kidneys showed higher NEP-mediated Ang (1-7) synthesis than Ang II formation, thus displaying a strong preference towards the reno-protective alternative RAS axis. In contrast, in CKD kidneys higher levels of Ang II were recorded, which originated from mast cell chymase activity.

CONCLUSIONS

Ang (1-7) is the dominant RAS peptide in healthy human kidneys with NEP rather than ACE2 being essential for its generation. Severe RAS dysregulation is present in CKD dictated by high chymase-mediated Ang II formation. Kidney RAS enzyme analysis might lead to novel therapeutic approaches for CKD.

Angiotensin receptor-neprilysin inhibitor for the treatment of heart failure: a review of recent evidence

Heart failure (HF) is a growing health concern in aging societies worldwide. Sacubitril/valsartan is changing the real-world treatment in the whole spectrum of HF. The beginning was the PARADIGM-HF trial published in 2014, which demonstrated the beneficial effects of inhibiting natriuretic peptide breakdown in combination with hindering the renin-angiotensin system in HF patients with a reduced ejection fraction. Subsequent large-scale randomized trials have evaluated angiotensin receptor-neprilysin inhibitor in HF patients with acute decompensation or with preserved ejection fraction. The post hoc analyses are being conducted as well. This review summarizes the recent evidence of sacubitril/ valsartan regarding patient-centered outcomes, based on randomized controlled trials and their associated studies.

Pharmacological interventions for heart failure in people with chronic kidney disease

BACKGROUND

Approximately half of people with heart failure have chronic kidney disease (CKD). Pharmacological interventions for heart failure in people with CKD have the potential to reduce death (any cause) or hospitalisations for decompensated heart failure. However, these interventions are of uncertain benefit and may increase the risk of harm, such as hypotension and electrolyte abnormalities, in those with CKD.

OBJECTIVES

This review aims to look at the benefits and harms of pharmacological interventions for HF (i.e., antihypertensive agents, inotropes, and agents that may improve the heart performance indirectly) in people with HF and CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies through 12 September 2019 in consultation with an Information Specialist and using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials of any pharmacological intervention for acute or chronic heart failure, among people of any age with chronic kidney disease of at least three months duration.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the records to identify eligible studies and extracted data on the following dichotomous outcomes: death, hospitalisations, worsening heart failure, worsening kidney function, hyperkalaemia, and hypotension. We used random effects meta-analysis to estimate treatment effects, which we expressed as a risk ratio (RR) with 95% confidence intervals (CI). We assessed the risk of bias using the Cochrane tool. We applied the GRADE methodology to rate the certainty of evidence.

MAIN RESULTS

One hundred and twelve studies met our selection criteria: 15 were studies of adults with CKD; 16 studies were conducted in the general population but provided subgroup data for people with CKD; and 81 studies included individuals with CKD, however, data for this subgroup were not provided. The risk of bias in all 112 studies was frequently high or unclear. Of the 31 studies (23,762 participants) with data on CKD patients, follow-up ranged from three months to five years, and study size ranged from 16 to 2916 participants. In total, 26 studies (19,612 participants) reported disaggregated and extractable data on at least one outcome of interest for our review and were included in our meta-analyses. In acute heart failure, the effects of adenosine A1-receptor antagonists, dopamine, nesiritide, or serelaxin on death, hospitalisations, worsening heart failure or kidney function, hyperkalaemia, hypotension or quality of life were uncertain due to sparse data or were not reported. In chronic heart failure, the effects of angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) (4 studies, 5003 participants: RR 0.85, 95% CI 0.70 to 1.02; I2 = 78%; low certainty evidence), aldosterone antagonists (2 studies, 34 participants: RR 0.61 95% CI 0.06 to 6.59; very low certainty evidence), and vasopressin receptor antagonists (RR 1.26, 95% CI 0.55 to 2.89; 2 studies, 1840 participants; low certainty evidence) on death (any cause) were uncertain. Treatment with beta-blockers may reduce the risk of death (any cause) (4 studies, 3136 participants: RR 0.69, 95% CI 0.60 to 0.79; I2 = 0%; moderate certainty evidence). Treatment with ACEi or ARB (2 studies, 1368 participants: RR 0.90, 95% CI 0.43 to 1.90; I2 = 97%; very low certainty evidence) had uncertain effects on hospitalisation for heart failure, as treatment estimates were consistent with either benefit or harm. Treatment with beta-blockers may decrease hospitalisation for heart failure (3 studies, 2287 participants: RR 0.67, 95% CI 0.43 to 1.05; I2 = 87%; low certainty evidence). Aldosterone antagonists may increase the risk of hyperkalaemia compared to placebo or no treatment (3 studies, 826 participants: RR 2.91, 95% CI 2.03 to 4.17; I2 = 0%; low certainty evidence). Renin inhibitors had uncertain risks of hyperkalaemia (2 studies, 142 participants: RR 0.86, 95% CI 0.49 to 1.49; I2 = 0%; very low certainty). We were unable to estimate whether treatment with sinus node inhibitors affects the risk of hyperkalaemia, as there were few studies and meta-analysis was not possible. Hyperkalaemia was not reported for the CKD subgroup in studies investigating other therapies. The effects of ACEi or ARB, or aldosterone antagonists on worsening heart failure or kidney function, hypotension, or quality of life were uncertain due to sparse data or were not reported. Effects of anti-arrhythmic agents, digoxin, phosphodiesterase inhibitors, renin inhibitors, sinus node inhibitors, vasodilators, and vasopressin receptor antagonists were very uncertain due to the paucity of studies.

AUTHORS' CONCLUSIONS

The effects of pharmacological interventions for heart failure in people with CKD are uncertain and there is insufficient evidence to inform clinical practice. Study data for treatment outcomes in patients with heart failure and CKD are sparse despite the potential impact of kidney impairment on the benefits and harms of treatment. Future research aimed at analysing existing data in general population HF studies to explore the effect in subgroups of patients with CKD, considering stage of disease, may yield valuable insights for the management of people with HF and CKD.

Sacubitril/Valsartan: Updates and Clinical Evidence for a Disease-Modifying Approach

New therapeutic strategies aimed to tackle the rising socio-economic burden of heart failure (HF) have become an impelling priority. The new pharmacological class of angiotensin (Ang) receptor-neprilysin inhibitors (ARNI) prompted a real conceptual change in the treatment of HF moving from only the inhibition of the renin-Ang-aldosterone system and sympathetic nervous system to a strategy based on the concomitant pharmacological enhancement of endogenous natriuretic peptides. Sacubitril/valsartan, a first-in-class ARNI, has reduced the primary composite endpoint of cardiovascular death or HF hospitalisation, sudden cardiac death, disease progression and improved quality of life, compared with enalapril, in patients on evidence-based contemporary medical therapy. Our review underlines the increasing body of evidence supporting the efficacy of sacubitril/valsartan, which may be considered a new disease-modifying therapy and, after about 30 years of research, a real step forward in HF pharmacological therapy.

Potential of Renin-Angiotensin-Aldosterone System Modulations in Diabetic Kidney Disease: Old Players to New Hope!

Due to a tragic increase in the incidences of diabetes globally, diabetic kidney disease (DKD) has emerged as one of the leading causes of end-stage renal diseases (ESRD). Hyperglycaemia-mediated overactivation of the renin-angiotensin-aldosterone system (RAAS) is key to the development and progression of DKD. Consequently, RAAS inhibition by angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARBs) is the first-line therapy for the clinical management of DKD. However, numerous clinical and preclinical evidences suggested that RAAS inhibition can only halt the progression of the DKD to a certain extent, and they are inadequate to cure DKD completely. Recent studies have improved understanding of the complexity of the RAAS. It consists of two counter-regulatory arms, the deleterious pressor arm (ACE/angiotensin II/AT1 receptor axis) and the beneficial depressor arm (ACE2/angiotensin-(1-7)/Mas receptor axis). These advances have paved the way for the development of new therapies targeting the RAAS for better treatment of DKD. In this review, we aimed to summarise the involvement of the depressor arm of the RAAS in DKD. Moreover, in modern drug discovery and development, an advance approach is the bispecific therapeutics, targeting two independent signalling pathways. Here, we discuss available reports of these bispecific drugs involving the RAAS as well as propose potential treatments based on neurohormonal balance as credible therapeutic strategies for DKD.

Do most patients with obesity or type 2 diabetes, and atrial fibrillation, also have undiagnosed heart failure? A critical conceptual framework for understanding mechanisms and improving diagnosis and treatment

Obesity and diabetes can lead to heart failure with preserved ejection fraction (HFpEF), potentially because they both cause expansion and inflammation of epicardial adipose tissue and thus lead to microvascular dysfunction and fibrosis of the underlying left ventricle. The same process also causes an atrial myopathy, which is clinically evident as atrial fibrillation (AF); thus, AF may be the first manifestation of HFpEF. Many patients with apparently isolated AF have latent HFpEF or subsequently develop HFpEF. Most patients with obesity or diabetes who have AF and exercise intolerance have increased left atrial pressures at rest or during exercise, even in the absence of diagnosed HFpEF. Among patients with AF, those who also have latent HFpEF have increased risk for systemic thromboembolism and death. The identification of HFpEF in patients with obesity or diabetes alters the risk-to-benefit relationship of commonly prescribed treatments. Bariatric surgery and statins can ameliorate AF and reduce the risk for HFpEF. Conversely, antihyperglycaemic drugs that promote adipogenesis or cause sodium retention (insulin and thiazolidinediones) may increase the risk for heart failure in patients with an underlying ventricular myopathy. Patients with obesity and diabetes who undergo catheter ablation for AF are at increased risk for AF recurrence and for post-ablation increases in pulmonary venous pressures and worsening heart failure, especially if HFpEF coexists. Therefore, AF may be the earliest indicator of HFpEF in patients with obesity or type 2 diabetes, and recognition of HFpEF alters the management of these patients.

Heart failure and its complications in patients with diabetes: Mounting evidence for a growing burden

Heart failure (HF) is one of the major challenges in the management of diabetes patients. Among subjects with diabetes, up to 20% could have HF. Conversely, diabetes prevalence in HF patients varies greatly from more than 10% up to 50%. When it is present, the risk of mortality and rehospitalization increases substantially. In addition, current evidence points to an increased risk of atrial fibrillation and sudden cardiac death in patients with diabetes. The inter-relation between diabetes cardiomyopathy, left ventricular hypertrophy, coronary artery disease and renal dysfunction indicates complex and intricate pathways. Despite the great value of clinical assessment and echocardiography, there is insufficient data to suggest systematic screening for HF in asymptomatic patients with diabetes. There is little evidence to indicate that improved glycaemic control improves HF outcome in this population. In the case of established HF, the general guidelines apply in diabetes patients. However, recent advances concerning glucose-lowering treatment in patients with cardiovascular disease suggest that the choice of glucose-lowering agent is of crucial interest and should be based on the patient’s phenotype. New drug classes, such as SGLT2 inhibitors, seem to be of particular benefit in these patients. In the future, new personalized strategies should aim at not only good control of the glycaemic level but also the reduction and possibly the prevention of HF onset.

Renal effects of Sacubitril/Valsartan in heart failure with reduced ejection fraction: a real life 1-year follow-up study

Real-life data confirming the favourable renal outcome in patients with heart failure (HF) treated with Sacubitril/Valsartan, previously found in several trials (RCTs), are still scant. We evaluated the renal effects of Sacubitril/Valsartan in a real-life sample of HF patients. Observational analysis of 54 consecutive outpatients affected by HF with reduced ejection fraction (HFrEF) and clinical indication for Sacubitril/Valsartan. Patients were evaluated at baseline (T0) and after six (T6) and twelve (T12) months after initiating Sacubitril/Valsartan and compared with a group of 30 historical controls. Mean age: 65.5 ± 11.7 years. Older patients: 29 (53.7%). Mean baseline estimated glomerular filtration rate (eGFR): 59.4 ± 19.2 ml/min/1.73 m2. Patients with chronic kidney disease (CKD), defined by an eGFR < 60 ml/min/1.73 m2, were 29 (53.7%). Sacubitril/Valsartan was less titrated in both older patients and patients with CKD. There were no changes in diuretics during follow-up. Systolic blood pressure (BP) decreased during follow-up (p = 0.014), while left ventricular ejection fraction (LVEF) slighly increased (p < 0.001). Renal function improved after 12 months compared to historical controls (p for interaction < 0.001) and a greater benefit was found in subjects aged < 65 years (p for interaction = 0.002) and patients with CKD (p for interaction = 0.009). A statistically (p = 0.009), but not clinically significant increase in serum potassium was also found, regardless of age and CKD. This is the first study focused on the renal effects of Sacubitril/Valsartan in HFrEF patients followed for 12 months in a real-life clinical context. The improved eGFR, despite lower BP, represents an important confirmation outside the peculiar world of RCTs.

Neprilysin, the kidney brush border neutral proteinase: a possible potential target for ischemic renal injury

Neprilysin (NEP) is an endogenously induced peptidase for modulating production and degradation of various peptides in humans. It is most abundantly present in kidney and regulates the intrinsic renal homeostatic mechanism. Recently, drugs inhibiting NEP have been approved for the use in heart failure. In the context of increased prevalence of ischemia associated renal failure, NEP could be an attractive target for treating kidney failure. In the kidney, targeting NEP may possess potential benefits as well as adverse consequences. The unfavorable outcomes of NEP are mainly attributed to the degradation of the natriuretic peptides (NPs). NPs are involved in the inhibition of the renin-angiotensin-aldosterone system (RAAS) and activation of the sympathetic system contributing to the tubular and glomerular injury. In contrary, NEP exerts the beneficial effect by converting angiotensin-1 (Ang I) to angiotensin-(1-7) (Ang-(1-7)), thus activating MAS-related G-protein coupled receptor. MAS receptor antagonizes angiotensin type I receptor (AT-1R), reduces reactive oxygen species (ROS) and inflammation, thus ameliorating renal injury. However, the association of NEP with complex cascades of renal ischemia remains vague. Therefore, there is a need to evaluate the putative mechanism of NEP and its overlap with other signaling cascades in conditions of renal ischemia.

Bioactive Signaling in Next-Generation Pharmacotherapies for Heart Failure: A Review

Importance

The standard pharmacotherapy for heart failure (HF), particularly HF with reduced ejection fraction (HFrEF), is primarily through the use of receptor antagonists, notably inhibition of the renin-angiotensin system by either angiotensin-converting enzyme inhibition or angiotensin II receptor blockade (ARB). However, the completed Prospective Comparison of ARNI With an ACE-Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial identified that the use of a single molecule (sacubitril/valsartan), which is an ARB and the neutral endopeptidase inhibitor (NEPi) neprilysin, yielded improved clinical outcomes in HFrEF compared with angiotensin-converting enzyme inhibition alone.

Observations

This review examined specific bioactive signaling pathways that would be potentiated by NEPi and how these would affect key cardiovascular processes relevant to HFrEF. It also addressed potential additive/synergistic effects of ARB. A number of biological signaling pathways that may be potentiated by sacubitril/valsartan were identified, including some novel candidate molecules, which will act in a synergistic manner to favorably alter the natural history of HFrEF.

Conclusions and Relevance

This review identified that activation rather than inhibition of specific receptor pathways provided favorable cardiovascular effects that cannot be achieved by renin-angiotensin system inhibition alone. Thus, an entirely new avenue of translational and clinical research lies ahead in which HF pharmacotherapies will move beyond receptor antagonist strategies.

Novel Therapeutic Approaches Targeting the Renin-Angiotensin System and Associated Peptides in Hypertension and Heart Failure

Despite the success of renin-angiotensin system (RAS) blockade by angiotensin-converting enzyme (ACE) inhibitors and angiotensin II type 1 receptor (AT1R) blockers, current therapies for hypertension and related cardiovascular diseases are still inadequate. Identification of additional components of the RAS and associated vasoactive pathways, as well as new structural and functional insights into established targets, have led to novel therapeutic approaches with the potential to provide improved cardiovascular protection and better blood pressure control and/or reduced adverse side effects. The simultaneous modulation of several neurohumoral mediators in key interconnected blood pressure-regulating pathways has been an attractive approach to improve treatment efficacy, and several novel approaches involve combination therapy or dual-acting agents. In addition, increased understanding of the complexity of the RAS has led to novel approaches aimed at upregulating the ACE2/angiotensin-(1-7)/Mas axis to counter-regulate the harmful effects of the ACE/angiotensin II/angiotensin III/AT1R axis. These advances have opened new avenues for the development of novel drugs targeting the RAS to better treat hypertension and heart failure. Here we focus on new therapies in preclinical and early clinical stages of development, including novel small molecule inhibitors and receptor agonists/antagonists, less conventional strategies such as gene therapy to suppress angiotensinogen at the RNA level, recombinant ACE2 protein, and novel bispecific designer peptides.

Effects of Sacubitril/Valsartan Versus Irbesartan in Patients With Chronic Kidney Disease

BACKGROUND

Sacubitril/valsartan reduces the risk of cardiovascular mortality among patients with heart failure with reduced ejection fraction, but its effects on kidney function and cardiac biomarkers in people with moderate to severe chronic kidney disease are unknown.

METHODS

The UK HARP-III trial (United Kingdom Heart and Renal Protection-III), a randomized double-blind trial, included 414 participants with an estimated glomerular filtration rate (GFR) 20 to 60 mL/min/1.73 m² who were randomly assigned to sacubitril/valsartan 97/103 mg twice daily versus irbesartan 300 mg once daily. The primary outcome was measured GFR at 12 months using ANCOVA with adjustment for each individual's baseline measured GFR. All analyses were by intention to treat.

RESULTS

In total, 207 participants were assigned to sacubitril/valsartan and 207 to irbesartan. Baseline measured GFR was 34.0 (SE, 0.8) and 34.7 (SE, 0.8) mL/min/1.73 m², respectively. At 12 months, there was no difference in measured GFR: 29.8 (SE 0.5) among those assigned sacubitril/valsartan versus 29.9 (SE, 0.5) mL/min/1.73 m² among those assigned irbesartan; difference, -0.1 (0.7) mL/min/1.73 m². Effects were similar in all prespecified subgroups. There was also no significant difference in estimated GFR at 3, 6, 9, or 12 months and no clear difference in urinary albumin:creatinine ratio between treatment arms (study average difference, -9%; 95% CI, -18 to 1). However, compared with irbesartan, allocation to sacubitril/valsartan reduced study average systolic and diastolic blood pressure by 5.4 (95% CI, 3.4-7.4) and 2.1 (95% CI, 1.0-3.3) mm Hg and levels of troponin I and N terminal of prohormone brain natriuretic peptide (tertiary end points) by 16% (95% CI, 8-23) and 18% (95% CI, 11-25), respectively. The incidence of serious adverse events (29.5% versus 28.5%; rate ratio, 1.07; 95% CI, 0.75-1.53), nonserious adverse reactions (36.7% versus 28.0%; rate ratio, 1.35; 95% CI, 0.96-1.90), and potassium ≥5.5 mmol/L (32% versus 24%, P=0.10) was not significantly different between randomized groups.

CONCLUSIONS

Over 12 months, sacubitril/valsartan has similar effects on kidney function and albuminuria to irbesartan, but it has the additional effect of lowering blood pressure and cardiac biomarkers in people with chronic kidney disease.

CLINICAL TRIAL REGISTRATION

URL: http://www.isrctn.com . Unique identifier: ISRCTN11958993.