The Mechanism of Action of LCZ696

Possible role of LCZ696 in atherosclerosis: new inroads and perspective

LCZ696 blocks both angiotensin receptor type 1 (ATR1) and neprilysin (NEP), which are intricate in the degradation of natriuretic peptides (NPs) and other endogenous peptides. It has been shown NEP inhibitors and LCZ696 could be effectively in the management of atherosclerosis (AS). However, the underlying mechanism of LCZ696 in AS is needed to be clarified entirely. Hence, this review is directed to reconnoiter the mechanistic role of LCZ696 in AS. The anti-inflammatory role of LCZ696 is related to the inhibition of transforming growth factor beta (TGF-β)-activated kinase 1 (TAK) and nod-like receptor pyrin 3 receptor (NLRP3) inflammasome. Moreover, LCZ696, via inhibition of pro-inflammatory cytokines, oxidative stress, apoptosis and endothelial dysfunction can attenuate the development and progression of AS. In conclusion, LCZ696 could be effective in the management of AS through modulation of inflammatory and oxidative signaling. Preclinical and clinical studies are recommended in this regard.

Study on the Effects of Angiotensin Receptor/Neprilysin Inhibitors on Renal Haemodynamics in Healthy Dogs

An angiotensin receptor/neprilysin inhibitor (ARNI), a heart failure treatment, is a combination drug made up of sacubitril, a neprilysin inhibitor, and valsartan, a vascular receptor blocker. No human or veterinary studies regarding the effect of ARNI on renal haemodynamics in the absence of cardiac or renal issues exist. Therefore, we investigated the effect of ARNI on renal haemodynamics in five healthy dogs. ARNI was administered to all five dogs at an oral dose of 20 mg/kg twice daily for 4 weeks. Renal haemodynamics were assessed on the day before ARNI administration (BL), on Day 7, and on Day 28. The glomerular filtration rate (GFR) significantly increased on Day 28 compared to BL and Day 7, whereas renal plasma flow increased on Day 7 and Day 28 compared to BL. Systolic blood pressure significantly decreased between BL and Day 28. Plasma atrial natriuretic peptide (ANP) concentrations increased on Day 7 compared to BL. Additionally, ANP concentrations increased on Day 28 in three of the five dogs. Different ANP concentrations were observed in the remaining two dogs. Both urine output volume and heart rate remained relatively stable and did not exhibit significant change. In conclusion, ARNI may enhance renal haemodynamics in healthy dogs. ARNI could be a valuable drug for treating both heart and kidney disease in dogs.

Sacubitril/valsartan alleviates sunitinib-induced cardiac fibrosis and oxidative stress via improving TXNIP/TRX system and downregulation of NF-ĸB/Wnt/β-catenin/SOX9 signaling

We aimed in this study to investigate the possible cardioprotective effects of sacubitril/valsartan against sunitinib-induced cardiac fibrosis (CF) and oxidative stress via targeting thioredoxin-interacting protein/thioredoxin (TXNIP/TRX) system and nuclear factor-kappa B (NF-κB)/Wingless-related MMTV integration site (Wnt)/β-catenin/Sex-determining region Y box 9 (SOX9) signaling. CF was induced in male Wistar albino rats by cumulative dose of sunitinib (300 mg/kg, given over 4 weeks as: 25 mg/kg orally, three times a week), which were co-treated with sacubitril/valsartan (68 mg/kg/day, orally) for four weeks. Significant elevation in blood pressure, cardiac inflammatory and fibrotic markers besides cardiac dysfunction were observed. These alterations were associated with disruption of TXNIP/TRX system, upregulation of NF-κB/Wnt/β-catenin/SOX9 pathway along with marked increase in lysyl oxidase (LOX) and matrix metalloproteinase-1 (MMP-1) expressions and extensive deposition of collagen fibers in cardiac tissues. Luckily, sacubitril/valsartan was able to reverse all of the aforementioned detrimental effects in sunitinib-administered rats. These findings illustrate a potential role of sacubitril/valsartan in alleviating CF and oxidative stress induced by sunitinib via antioxidant, anti-inflammatory and antifibrotic properties. These remarkable effects of sacubitril/valsartan were mediated by its ability to improve TXNIP/TRX system and downregulate NF-κB/Wnt/β-catenin/SOX9 signaling in addition to decreasing LOX and MMP-1 expressions in cardiac tissues. In summary, this study highlights sacubitril/valsartan as a potential therapeutic agent in mitigating CF and oxidative stress especially in cancer cases treated with sunitinib.

LCZ696, an Angiotensin Receptor-Neprilysin Inhibitor, Ameliorates Endothelial Dysfunction in Diabetic C57BL/6 Mice

AIMS

LCZ696 (sacubitril/valsartan) exerts cardioprotective effects. Recent studies have suggested that it improves the endothelial function; however, the underlying mechanisms have not been thoroughly investigated. We investigated whether LCZ696 ameliorates diabetes-induced endothelial dysfunction.

METHODS

Diabetes was induced using streptozotocin in 8-week-old male C57BL/6 mice. Diabetic mice were randomly assigned to receive LCZ696 (100 mg/kg/day), valsartan (50 mg/kg/day), or a vehicle for three weeks. The endothelium-dependent and endothelium-independent vascular responses of the aortic segments were determined based on the response to acetylcholine and sodium nitroprusside, respectively. Human umbilical vein endothelial cells (HUVEC) and aortic segments obtained from C57BL/6 mice were used to perform in vitro and ex vivo experiments, respectively.

RESULTS

LCZ696 and valsartan reduced the blood pressure in diabetic mice (P＜0.05). The administration of LCZ696 (P＜0.001) and valsartan (P＜0.01) ameliorated endothelium-dependent vascular relaxation, but not endothelium-independent vascular relaxation, under diabetic conditions. LCZ696, but not valsartan, increased eNOSSer1177 (P=0.06) and Akt (P＜0.05) phosphorylation in the aorta. In HUVEC, methylglyoxal (MGO), a major precursor of advanced glycation end products, decreased eNOSSer1177 phosphorylation (P＜0.05) and increased eNOSThr495 phosphorylation (P＜0.001). However, atrial natriuretic peptide (ANP) reversed these effects. ANP also ameliorated the MGO-induced impairment of endothelium-dependent vascular relaxation in the aortic segments (P＜0.05), although L-NAME completely blocked this effect (P＜0.001).

CONCLUSION

LCZ696 ameliorated diabetes-induced endothelial dysfunction by increasing the bioavailability of ANP. Our findings suggest that LCZ696 has a vascular protective effect in a diabetic model and highlight that it may be more effective than valsartan.

Reverse Remodeling Effects of Sacubitril-Valsartan: Structural and Functional Optimization in Stage C Heart Failure

Sacubitril-valsartan, an angiotensin receptor-neprilysin inhibitor, reduces all-cause mortality and the rate of heart failure hospitalizations in patients with heart failure with reduced ejection fraction. This study aimed to elucidate the benefits of initiating sacubitril-valsartan on ventricular remodeling in patients previously optimized on guideline-directed medical therapy. In this prospective, single-arm longitudinal study, 40 patients with heart failure with reduced ejection fraction who were optimized on guideline-directed medical therapy were transitioned to sacubitril-valsartan. The primary end point was the change in left ventricular (LV) volume at 1 year as assessed by 3-dimensional transthoracic echocardiography. Other echocardiographic end points included change in LV-function and change in right ventricular (RV) size and function. The mean age was 55 ± 12 years, and 63% were male. At 1 year, LV end-diastolic volume decreased from 242 ± 71 to 157 ± 57 ml (p <0.001) with a corresponding increase in LV ejection fraction from 32 ± 7% to 44 ± 9% (p <0.001). RV end-diastolic volume decreased from 151 ± 51 to 105 ±45 ml (p <0.001). Although RV ejection fraction did not change (51 ± 8 vs 51 ± 10; p = 0.35), RV global longitudinal strain improved from -14.9 ± 3.4 % to -19.3 ± 4.3% (p <0.001). When added to standard medical therapy for heart failure, sacubitril-valsartan induces significant remodeling of both the right and left ventricles as assessed by 3-dimensional echocardiography.

LCZ696 (sacubitril/valsartan) mitigates cyclophosphamide-induced premature ovarian failure in rats; the role of TLR4/NF-κB/NLRP3/Caspase-1 signaling pathway

AIM

Cyclophosphamide (CP) is used to treat a variety of cancers and autoimmune illnesses. CP has been found to frequently cause premature ovarian failure (POF). The study's objective was to assess LCZ696's potential for protection against CP-induced POF in a rat model.

MAIN METHODS

Rats were randomly assigned into seven groups as follows: control, valsartan (VAL), LCZ696, CP, CP + VAL, CP + LCZ696, and CP + triptorelin (TRI). Ovarian malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), interleukin-18 (IL-18), IL-1β, and tumor necrosis factor-alpha (TNF-α) were assessed using ELISA. Serum anti-mullerian hormone (AMH), estrogen, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were also measured using ELISA. The expression of NLRP3/Caspase-1/GSDMD C-NT and TLR4/MYD88/NF-B P65 proteins was estimated using western blot assay. The histopathology of the ovaries was also investigated. The estrous cycle, body, and ovarian weights were also monitored.

KEY FINDINGS

CP treatment significantly elevated levels of MDA, IL-18, IL-1β, TNF-α, FSH, LH, and up-regulated TLR4/NF-κB/NLRP3/Caspase-1 proteins, as compared to the control group, however, ovarian follicles count, and levels of GSH, SOD, AMH, and estrogen were reduced with CP administration. All the aforementioned biochemical and histological abnormalities were considerably alleviated by the LCZ696 therapy compared to valsartan alone.

SIGNIFICANCE

LCZ696 effectively mitigated CP-induced POF, offering promising protection that could be related to its suppression power on NLRP3-induced pyroptosis and TLR4/NF-B P65 pathway.

Combined Left Ventricular Ejection Fraction and N-Terminal pro-B-type Natriuretic Peptide after Sacubitril/Valsartan for Predicting Outcomes in Patients with Heart Failure with Reduced Ejection Fraction

Background

The aim of this study was to determine whether a combined increase of ≥ 10% in left ventricular ejection fraction (LVEF) and decrease in N-terminal pro-B-type natriuretic peptide (NT pro-BNP) to < 1000 pg/mL after treatment with sacubitril/valsartan (SAC/VAL) in patients with heart failure with reduced ejection fraction (HFrEF) translated to better treatment outcomes in a real-world Taiwanese population.

Methods

This is a single-center, prospective, non-randomized, observational study. Consecutive patients with HFrEF were treated with SAC/VAL and followed up for at least 12 months. The primary endpoint was a change in LVEF and reduction in NT pro-BNP at 12 months. The secondary outcomes were death and heart failure (HF) rehospitalization.

Results

A total of 105 patients were analyzed after 12 months of SAC/VAL treatment. The mean age was 66.0 ± 11.6 years, and the mean LVEF and NT pro-BNP were 33.6 ± 6.7% and 4462.7 ± 5851.7 pg/mL respectively. The mean LVEF significantly increased to 50.5 ± 10.3% (p < 0.001), while NT pro-BNP decreased to 1270.3 ± 2368.2 pg/mL (p = 0.001) at 12 months, with the greatest changes occurring in the first 3 months of treatment (p < 0.001). Five patients died and 12 were rehospitalized for HF. None of the patients in the responder group died compared to 5 deaths in the non-responder group (p = 0.039). Combined ≥ 10% LVEF increase and NT pro-BNP of < 1000 pg/mL was an independent predictor of death and HF rehospitalization (p = 0.019).

Conclusions

SAC/VAL treatment resulted in significant improvements in LVEF, reduced NT pro-BNP level, death and HF hospitalization. Taken separately, an NT pro-BNP level of < 1000 pg/mL was a better predictor than ≥ 10% LVEF increase. Combining both variables predicted fewer deaths and HF rehospitalizations. Even with failure to reach the target dose, SAC/VAL still had significantly beneficial treatment outcomes in Taiwanese patients.

Molecular Mechanisms and Therapeutic Implications of Endothelial Dysfunction in Patients with Heart Failure

Heart failure is a complex medical syndrome that is attributed to a number of risk factors; nevertheless, its clinical presentation is quite similar among the different etiologies. Heart failure displays a rapidly increasing prevalence due to the aging of the population and the success of medical treatment and devices. The pathophysiology of heart failure comprises several mechanisms, such as activation of neurohormonal systems, oxidative stress, dysfunctional calcium handling, impaired energy utilization, mitochondrial dysfunction, and inflammation, which are also implicated in the development of endothelial dysfunction. Heart failure with reduced ejection fraction is usually the result of myocardial loss, which progressively ends in myocardial remodeling. On the other hand, heart failure with preserved ejection fraction is common in patients with comorbidities such as diabetes mellitus, obesity, and hypertension, which trigger the creation of a micro-environment of chronic, ongoing inflammation. Interestingly, endothelial dysfunction of both peripheral vessels and coronary epicardial vessels and microcirculation is a common characteristic of both categories of heart failure and has been associated with worse cardiovascular outcomes. Indeed, exercise training and several heart failure drug categories display favorable effects against endothelial dysfunction apart from their established direct myocardial benefit.

Mechanisms of current therapeutic strategies for heart failure: more questions than answers?

Heart failure (HF) is a complex, multifactorial and heterogeneous syndrome with substantial mortality and morbidity. Over the last few decades, numerous attempts have been made to develop targeted therapies that may attenuate the known pathophysiological pathways responsible for causing the progression of HF. However, therapies developed with this objective have sometimes failed to show benefit. The pathophysiological construct of HF with numerous aetiologies suggests that interventions with broad mechanisms of action which simultaneously target more than one pathway maybe more effective in improving the outcomes of patients with HF. Indeed, current therapeutics with clinical benefits in HF have targeted a wider range of intermediate phenotypes. Despite extensive scientific breakthroughs in HF research recently, questions persist regarding the ideal therapeutic targets which may help achieve maximum benefit. In this review, we evaluate the mechanism of action of current therapeutic strategies, the pathophysiological pathways they target and highlight remaining knowledge gaps regarding the mode of action of these interventions.

The Difference between Sacubitril Valsartan and Valsartan on Vascular Endothelial Function, APN, MMP-9, and BNP Levels in Patients with Hypertension and Chronic Heart Failure

Background

Sacubitril valsartan and valsartan are the first new drugs approved for angiotensin receptor neprilysin lysine inhibitors (ARNIs) in outpatients with chronic heart failure (CHF) and hypertension. Compared with enalapril, sacubitril valsartan and valsartan have been shown to reduce the mortality and morbidity of cardiovascular diseases. However, there is little actual evidence regarding the efficacy of ARNIs in hypertensive patients with CHF.

Methods

From January 2019 to January 2021, 60 patients with hypertension and chronic heart failure were diagnosed and treated in our hospital. The patients were randomly divided into an observation group and a control group, with 30 cases in each group. The control group was given valsartan, the observation group was given sacubitril valsartan, and both groups were treated for six months. The endothelium-dependent vasodilation (EDD) function of the brachial artery and serum nitric oxide (NO), endothelin-1 (ET-1), carotid artery intima-media thickness, and glomerular filtration, excess rate (eGFR), and left ventricular ejection fraction (LVEF) were compared between the two groups of patients before and after treatment. The serum adiponectin (APN), matrix metalloproteinase-9 (MMP-9), and brain natriuretic peptide (BNP) levels were compared before and after treatment.

Results

The total effective rate of treatment in the research group was higher than that in the control group (P < 0.05). After treatment, the cardiac function indexes LVESD and LVEDD of the two groups of patients were lower than before treatment, and LVEF was higher than before treatment, and the improvement rate of the treatment group was better than that of the control group (P < 0.05). After treatment, the serum APN of the two groups was higher than before treatment, the levels of MMP-9 and BNP were lower than before treatment, and the improvement rate of patients in the treatment group was better than that of patients in the control group (P < 0.05). There was no statistically significant in the levels of EDD, NO, and ET-1 of the two groups of patients before treatment (P < 0.05). After treatment, compared with the control group, the EDD function and NO level of the research group were significantly increased (P < 0.05), and the level of ET-1 was significantly reduced (P < 0.05). There was no statistically significant difference in carotid artery intima-media thickness, glomerular filtration rate, and left ventricular ejection fraction before and after treatment in the two groups (P < 0.05).

Conclusion

In the treatment of hypertension and chronic heart failure, sacubitril valsartan can improve the clinical symptoms of patients to the greatest extent and can significantly improve the levels of LVEF, LVEDD, NT-proBNP, heart function, and other indicators. Sacubitril valsartan can increase serum APN levels, reduce MMP-9 and BNP levels, and have good clinical effects. Sacubitril valsartan has a protective effect on the vascular endothelial function of patients with hypertension and CHF. However, these results need to be confirmed in studies involving more subjects and require longer follow-up times.

An Overview of Clinically Imperative and Pharmacodynamically Significant Drug Interactions of Renin-Angiotensin-Aldosterone System (RAAS) Blockers

INTRODUCTION

Hypertension is a leading cause of cardiovascular disease and chronic kidney disease, resulting in premature death and disability. The Renin-Angiotensin-Aldosterone System (RAAS) blockers, including Angiotensin-Converting Enzyme (ACE) inhibitors or Angiotensin Receptor Blockers (ARBs), are used as first-line antihypertensive therapy to treat hypertensive patients with comorbidities, including diabetes, ischemic heart disease, heart failure, and chronic kidney disease. The use of RAS blockers is associated with the risks, such as hyperkalemia, angioedema, etc. The drugs potentiating them interact pharmacodynamically, resulting in adverse consequences. This review article focuses on the clinically important drug interactions of RAAS blockers.

MATERIALS AND METHODS

The electronic databases, such as Medline/PubMed Central/PubMed, Google Scholar, ScienceDirect, Cochrane Library, Directory of Open Access Journals (DOAJ), Embase, and reference lists were searched to identify relevant articles.

RESULTS

The risk of hyperkalemia may be enhanced potentially in patients receiving a RAS blocker and potassium-sparing diuretics, potassium supplements, trimethoprim, adrenergic betablockers, antifungal agents, calcineurin inhibitors, pentamidine, heparins or an NSAID, concomitantly. The patients taking ACE inhibitors and mTOR inhibitors, DPP4 inhibitors, alteplase, or sacubitril/valsartan concurrently may be at increased risk of developing angioedema.

CONCLUSION

Clinicians, pharmacists, and other healthcare practitioners should be accountable for medication safety. To avoid adverse implications, prescribers and pharmacists must be aware of the drugs that interact with RAAS blockers.

The effects of sacubitril/valsartan on heart failure with preserved ejection fraction: a meta-analysis

BACKGROUND

Compared with angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, Sacubitril/Valsartan has been reported to have superior results. However, the effects of sacubitril/valsartan on heart failure with preserved ejection fraction (HFpEF) are still in dispute.

OBJECTIVES

This study aims to evaluate the effects of sacubitril/valsartan on the treatment of HFpEF patients.

METHODS

PubMed, Embase, Web of Science, Cochrane Library, and Clinicaltrials.gov were used to search for randomised controlled trials of sacubitril/valsartan in HFpEF patients from inception to 7 December 2020.

RESULTS

Four studies, with a total of 7739 participants, met the inclusion criteria. The present meta-analysis results showed that compared with the control group, sacubitril/valsartan reduced the hospitalisation rate of HF in HFpEF patients [Risk Ratio(RR): 0.85; 95% confidence interval (CI): 0.79-0.93; p = 0.0002). Regarding all-cause mortality, cardiovascular mortality, and the improvement in NYHA class, sacubitril/valsartan did not show apparent advantages. Although sacubitril/valsartan was linked to increasing the risk of symptomatic hypotension (RR: 1.44; 95% CI: 1.25-1.66; p﹤0.00001), there was no evidence supporting the incidence of renal function worsening and hyperkalemia.

CONCLUSION

Our study shows that compared with valsartan or individualised medical therapy (IMT), there were not different between the two groups except for the hospitalisation rate which was favoured by Sacubitril/Valsartan treatment group for HFpEF patients.

Effectiveness of sacubitril/valsartan versus aldosterone antagonists in heart failure with reduced ejection fraction: A retrospective cohort study

STUDY OBJECTIVE

To assess the effectiveness of sacubitril/valsartan versus angiotensin receptor antagonist therapy for prevention of heart failure (HF)-related hospitalization and all-cause hospitalization in a large cohort of patients with heart failure with reduced ejection fraction (HFrEF).

DESIGN

Retrospective cohort study.

DATA SOURCE

IBM^® MarketScan^® research databases (2014-2018).

PATIENTS

Patients aged 18 years or older with their first HFrEF hospitalization on or after January 1, 2015, who initiated sacubitril/valsartan or angiotensin receptor antagonist after hospital discharge.

INTERVENTION

Sacubitril/Valsartan versus Angiotensin receptor antagonist.

MEASUREMENTS AND MAIN RESULTS

The index date was the first sacubitril/valsartan or angiotensin receptor antagonist fill date. After 1 up to 3 propensity score matching, Cox proportional hazards regression was used with robust variance estimators to compare HF-related and all-cause hospitalizations between treatments. Subgroup and sensitivity analyses were conducted to assess the robustness of the main analysis. After propensity score matching, 1,088 sacubitril/valsartan and 2,839 angiotensin receptor antagonist new users were included. The crude incidence of HF-related hospitalization was 13 per 100 person-years for sacubitril/valsartan users and 18 per 100 person-years for angiotensin receptor antagonist users. Compared with angiotensin receptor antagonist use, sacubitril/valsartan use was associated with 27% lower risk of HF-related hospitalization (adjusted hazard ratio, 0.73; 95% confidence interval, 0.58-0.91; p = 0.006) and 31% lower risk of all-cause hospitalization (adjusted hazard ratio, 0.69; 95% confidence interval, 0.61-0.79; p < 0.001). Subgroup analyses revealed no significant heterogeneity, including subpopulations with chronic kidney disease or coronary artery disease.

CONCLUSIONS

Compared with angiotensin receptor antagonists, sacubitril/valsartan was associated with lower risk of HF-related and all-cause hospitalizations. Our data suggest that, when added sequentially, sacubitril/valsartan should be the preferred initial agent over angiotensin receptor antagonists.

Protective Effects of Sacubitril/Valsartan on Cardiac Fibrosis and Function in Rats With Experimental Myocardial Infarction Involves Inhibition of Collagen Synthesis by Myocardial Fibroblasts Through Downregulating TGF-β1/Smads Pathway

Objectives: To investigate the effect and mechanism of sacubitril/valsartan on myocardial fibrosis in rats following experimental myocardial infarction and in TGF-β1-treated myocardial fibroblasts.

Methods: Male Sprague-Dawley (SD) rats were subjected to coronary artery ligation to establish myocardial infarction and intragastrically fed vehicle, valsartan (Val, 32 mg/kg, once-daily) or sacubitril/valsartan (Sac/Val, 68 mg/kg, once-daily) for 4 weeks. In parallel, myocardial fibroblasts (MFs) isolated from neonatal SD rats were exposed to hypoxia and treated with TGF-β1 (5 ng/ml) plus vehicle, Val (10⁷–10^–5 M) or Sac/Val (10⁷–10⁵ M). Rat cardiac function and fibrosis were measured by echocardiography and histological method, respectively. MFs viability and collagen synthesis were determined by cell counting kit-8 and enzyme-linked immunosorbent assay, respectively. Protein expressions of TGF-β1, Smad3, phosphorylated Smad3 (p-Smad3), and p-Smad3 subcellular localization were detected by immunoblotting and immunocytochemistry.

Results: Sac/Val significantly improved cardiac structure and function in rats after myocardial infarction, including decreased left ventricular end-diastolic diameter and interventricular septal thickness, increased ejection fraction, and reduced myocardial collagen volume fraction and type Ⅰ and type Ⅲ collagen levels, and this effect was superior to that of Val. Besides, Sac/Val inhibited myocardial TGF-β1 and p-Smad3 protein expression better than Val. Mechanically, Sac/Val significantly attenuated TGF-β1-induced proliferation and collagen synthesis of MFs, and inhibit Smad3 phosphorylation and nucleus translocation, and this effect outperformed Val. Overexpression and silencing of Smad3 enhanced and reversed the inhibitory effects of Sac/Val on TGF-β1-induced collagen synthesis by MFs, respectively.

Conclusions: Sacubitril/valsartan improves cardiac function and fibrosis in rats after experimental myocardial infarction, and this effect is related to the inhibition of collagen synthesis in myocardial fibroblasts by inhibiting the TGF/Smads signaling pathway.

Current Understanding of the Right Ventricle Structure and Function in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a disease resulting in increased right ventricular (RV) afterload and RV remodeling. PAH results in altered RV structure and function at different scales from organ-level hemodynamics to tissue-level biomechanical properties, fiber-level architecture, and cardiomyocyte-level contractility. Biomechanical analysis of RV pathophysiology has drawn significant attention over the past years and recent work has found a close link between RV biomechanics and physiological function. Building upon previously developed techniques, biomechanical studies have employed multi-scale analysis frameworks to investigate the underlying mechanisms of RV remodeling in PAH and effects of potential therapeutic interventions on these mechanisms. In this review, we discuss the current understanding of RV structure and function in PAH, highlighting the findings from recent studies on the biomechanics of RV remodeling at organ, tissue, fiber, and cellular levels. Recent progress in understanding the underlying mechanisms of RV remodeling in PAH, and effects of potential therapeutics, will be highlighted from a biomechanical perspective. The clinical relevance of RV biomechanics in PAH will be discussed, followed by addressing the current knowledge gaps and providing suggested directions for future research.

Sacubitril/valsartan treatment has differential effects in modulating diabetic kidney disease in db/db mice and KKAy mice compared with valsartan treatment

Although renin-angiotensin blockade has shown beneficial outcomes in patients with diabetes, renal injury progresses in most of these patients. Therefore, there remains a need for new therapeutic targets in diabetic kidney disease. Enhancement of vasoactive peptides, such as natriuretic peptides, via neprilysin inhibition, has been a new approach. A first-in-class drug, sacubitril/valsartan (Sac/Val), a combination of the angiotensin II receptor blocker Val and neprilysin inhibitor prodrug Sac, has been shown to be more effective than renin-angiotensin blockade alone in the treatment of heart failure with reduced ejection fraction. In this study, we tested the effects of Sac/Val in diabetic kidney disease. We administered Sac/Val or Val to two type 2 diabetes mouse models, db/db mice or KKAy mice. After 3 mo of treatment, Sac/Val attenuated the progression of proteinuria, glomerulosclerosis, and podocyte loss in both models of diabetic mice. Val shared a similar improvement but to a lesser degree in some parameters compared with Sac/Val. Sac/Val but not Val decreased the blood glucose level in KKAy mice. Sac/Val exerted renal protection through coordinated effects on antioxidative stress and anti-inflammation. In both diabetic models, we revealed a new mechanism to cause inflammation, self-DNA-activated cGMP-AMP synthase-stimulator of interferon genes (cGAS-STING) signaling, which was activated in diabetic kidneys and prevented by Sac/Val or Val treatment. The present data suggest that Sac/Val has sufficient therapeutical potential to counter the pathophysiological effects of diabetic kidney disease, and its effectiveness could be better than Val alone.NEW & NOTEWORTHY The first-in-class drug sacubitril/valsartan, a combination of the angiotensin II receptor blocker valsartan and neprilysin inhibitor sacubitril, was tested for its effects in diabetic kidney disease using db/db mice and KKAy mice. We found that Sac/Val has sufficient therapeutical potential to counter the pathophysiological effects of diabetic kidney disease. We further revealed a new mechanism to cause inflammation, self-DNA-activated cGAS-STING signaling, which was activated in diabetic kidneys and prevented by sacubitril/valsartan or valsartan treatment.

Angiotensin Receptor-Neprilysin Inhibitors and the Natriuretic Peptide Axis

PURPOSE OF THE REVIEW

The purpose of this review is to describe the effects of angiotensin receptor neprilysin inhibitor (ARNI) therapy on the natriuretic peptide axis (NPA), with a particular focus on B-type natriuretic peptide (BNP), atrial natriuretic peptide (ANP), and C-type natriuretic peptide (CNP) to better understand the biology behind the improved outcomes in patients with heart failure with reduced ejection fraction (HFrEF).

RECENT FINDINGS

BNP, ANP, and CNP are the three main natriuretic peptides (NP); they share a common structure and ultimately mediate their actions by activating cyclic guanosine monophosphate (cGMP). ARNI therapy results in a decrease of N-terminal pro-BNP (NT-proBNP) and increase of BNP levels respectively. It is been questioned whether these changes may result from unique laboratory assays characteristics rather than actual biological implications. It appears to be that the prognostic accuracy of BNP for cardiovascular outcomes remains independent and comparable to that of NT-proBNP while on ARNI therapy. ANP levels also increase with ARNI therapy, but no consistent change has been described for CNP levels. There is evidence that the changes in BNP and NT-proBNP correlate with improvement in echocardiographic parameters of volume and function. The dual effect of neprilysin inhibition and angiotensin receptor blockade has substantial implications on the natriuretic peptide axis (NPA). The changes seen in BNP and NT-proBNP specifically have shown to correlate with improvement in echocardiographic parameters. Further results exploring the biologic effects of ARNI therapy on other NPs are still pending and likely will provide further insights in the mechanisms behind the improvement in cardiac function and clinical outcomes.

Acute pulmonary pressure change after transition to sacubitril/valsartan in patients with heart failure reduced ejection fraction

Aims

Sacubitril/valsartan combines renin–angiotensin–aldosterone system inhibition with amplification of natriuretic peptides. In addition to well‐described effects, natriuretic peptides exert direct effects on pulmonary vasculature. The effect of sacubitril/valsartan on pulmonary artery pressure (PAP) has not been fully defined.

Methods and results

This was a retrospective case‐series of PAP changes following transition from angiotensin‐converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) to sacubitril/valsartan in patients with heart failure reduced ejection fraction and a previously implanted CardioMEMS™ sensor. Pre‐sacubitril/valsartan and post‐sacubitril/valsartan PAPs were compared for each patient by examining averaged consecutive daily pressure readings from 1 to 5 days before and after sacubitril/valsartan exposure. PAP changes were also compared between patients based on elevated trans‐pulmonary gradients (trans‐pulmonary gradient ≥ 12 mmHg) at time of CardioMEMS™ sensor implantation. The cohort included 18 patients, 72% male, mean age 60.1 ± 13.6 years. There was a significant decrease in PAPs associated with transition from ACEI/ARB to sacubitril/valsartan. The median (interquartile range) pre‐treatment and post‐treatment change in mean, systolic and diastolic PAPs were −3.6 (−9.8, −0.7) mmHg (P < 0.001), −6.5 (−15.0, −2.0) mmHg (P = 0.001), and −2.5 (−5.7, −0.7) (P = 0.001), respectively. The decrease in PAPs was independent of trans‐pulmonary gradient (F(1,16) = 0.49, P = 0.49).

Conclusions

In this retrospective case series, transition from ACEI/ARB to sacubitril/valsartan was associated with an early and significant decrease in PAPs.

Sacubitril-valsartan improves conduit vessel function and functional capacity and reduces inflammation in heart failure with reduced ejection fraction

The Prospective comparison of ARNI with angiotensin-converting enzyme inhibitor to Determine Impact on Global Mortality and morbidity in Heart Failure trial identified a marked reduction in the risk of death and hospitalization for heart failure in patients with heart failure with reduced ejection fraction (HFrEF) treated with sacubitril-valsartan (trade name Entresto), but the physiological processes underpinning these improvements are unclear. We tested the hypothesis that treatment with sacubitril-valsartan improves peripheral vascular function, functional capacity, and inflammation in patients with HFrEF. We prospectively studied patients with HFrEF (n = 11, 10 M/1 F, left ventricular ejection fraction = 27 ± 8%) on optimal, guideline-directed medical treatment who were subsequently prescribed sacubitril-valsartan (open-label, uncontrolled, and unblinded). Peripheral vascular function [brachial artery flow-mediated dilation (FMD, conduit vessel function) and reactive hyperemia (RH, microvascular function)], functional capacity [six-minute walk test (6MWT) distance], and the proinflammatory biomarkers tumor necrosis factor-α (TNF-α) and interleukin-18 (IL-18) were obtained at baseline and at 1, 2, and 3 mo of treatment. %FMD improved after 1 mo of treatment, and this favorable response persisted for months 2 and 3 (baseline: 3.25 ± 1.75%; 1 mo: 5.23 ± 2.36%; 2 mo: 5.81 ± 1.79%; 3 mo: 6.35 ± 2.77%), whereas RH remained unchanged. 6MWT distance increased at months 2 and 3 (baseline: 420 ± 92 m; 1 mo: 436 ± 98 m; 2 mo: 465 ± 115 m; 3 mo: 460 ± 110 m), and there was a sustained reduction in TNF-α (baseline: 2.38 ± 1.35 pg/mL; 1 mo: 2.06 ± 1.52 pg/mL; 2 mo: 1.95 ± 1.34 pg/mL; 3 mo: 1.92 ± 1.37 pg/mL) and a reduction in IL-18 at month 3 (baseline: 654 ± 150 pg/mL; 1 mo: 595 ± 140 pg/mL; 2 mo: 601 ± 176 pg/mL; 3 mo: 571 ± 127 pg/mL). This study provides new evidence for the potential of this new drug class to improve conduit vessel function, functional capacity, and inflammation in patients with HFrEF.NEW & NOTEWORTHY We observed an approximately twofold improvement in conduit vessel function (brachial artery FMD), increased functional capacity (6MWT distance), and a reduction in inflammation (TNF-α and IL-18) following 3 mo of sacubitril-valsartan therapy. These findings provide important new information concerning the physiological mechanisms by which this new drug class provokes favorable changes in HFrEF pathophysiology.

Increasing heart vascularisation after myocardial infarction using brain natriuretic peptide stimulation of endothelial and WT1+ epicardial cells

Brain natriuretic peptide (BNP) treatment increases heart function and decreases heart dilation after myocardial infarction (MI). Here, we investigated whether part of the cardioprotective effect of BNP in infarcted hearts related to improved neovascularisation. Infarcted mice were treated with saline or BNP for 10 days. BNP treatment increased vascularisation and the number of endothelial cells in all areas of infarcted hearts. Endothelial cell lineage tracing showed that BNP directly stimulated the proliferation of resident endothelial cells via NPR-A binding and p38 MAP kinase activation. BNP also stimulated the proliferation of WT1⁺ epicardium-derived cells but only in the hypoxic area of infarcted hearts. Our results demonstrated that these immature cells have a natural capacity to differentiate into endothelial cells in infarcted hearts. BNP treatment increased their proliferation but not their differentiation capacity. We identified new roles for BNP that hold potential for new therapeutic strategies to improve recovery and clinical outcome after MI.

A novel protective role of sacubitril/valsartan in cyclophosphamide induced lung injury in rats: impact of miRNA-150-3p on NF-κB/MAPK signaling trajectories

Cyclophosphamide (CP) is a chemotherapeutic agent that induces oxidative stress causing multiple organ damage. Sacubitril/valsartan, is a combined formulation of neprilysin inhibitor (sacubitril) and angiotensin II receptor blocker (valsartan), that induces the protective effect of brain natriuretic peptide. The aim of the current study is to investigate the prophylactic impacts of sacubitril/valsartan versus valsartan against CP-induced lung toxicity in rats. Rats were assigned randomly into 6 groups; control; received corn oil (2 ml/kg/day; p.o. for 6 days), sacubitril/valsartan (30 mg/kg; p.o. for 6 days), valsartan (15 mg/kg; p.o. for 6 days), CP (200 mg/kg; i.p. on day 5), sacubitril/valsartan + CP (30 mg/kg; p.o. for 6 days, 200 mg/kg; i.p. single dose on day 5, respectively), valsartan + CP (15 mg/kg; p.o. for 6 days, 200 mg/kg; i.p. single dose on day 5, respectively). Both sacubitril/valsartan and valsartan produced a significant decrease in the inflammation and fibrosis markers in the BALF, in comparison with the CP group. Both sacubitril/valsartan and valsartan produced an apparent decrease in the relative genes expression of miR-150-3p and NF-κB, as well as a significant decrease in the relative expression of P38 and ERK1/2 MAPKs and an increase in the relative gene expression of Nrf-2, compared to CP group. Intriguingly, sacubitril/valsartan , showed subtle superiority in almost all investigated parameters, compared to valsartan. In conclusion, sacubitril/valsartan effectively abrogated the CP induced lung inflammation and fibrosis, providing a potential promising protection that could be linked to their ability to inhibit miR-150-3p via inhibition of NF-κB and MAPK signaling pathways.

Current evidence of sacubitril/valsartan in the treatment of heart failure with reduced ejection fraction

Heart failure (HF) is one of the most common reasons for hospital admission in western countries. The measurement of the left ventricular ejection fraction is essential for the classification of HF and deciding on HF treatment. The treatment of HF has been improved in both diagnostic and therapeutic fields over the past two decades. The angiotensin receptor-neprilysin inhibitor decreased the cardiovascular mortality in patients with chronic HF with reduced ejection fraction. Sacubitril/valsartan (LCZ696) improves the imbalance between the renin-angiotensin-aldosterone and natriuretic peptide systems. We present the clinical efficacy, real-world experience, safety and tolerability, the relevance of etiology of cardiomyopathy, and gender differences and regulatory affairs of LCZ696 in the treatment of patients with HF with reduced ejection fraction.

Angiotensin Receptor-Neprilysin Inhibition Attenuates Right Ventricular Remodeling in Pulmonary Hypertension

Background

Pulmonary hypertension (PH) results in increased right ventricular (RV) afterload and ventricular remodeling. Sacubitril/valsartan (sac/val) is a dual acting drug, composed of the neprilysin inhibitor sacubitril and the angiotensin receptor blocker valsartan, that has shown promising outcomes in reducing the risk of death and hospitalization for chronic systolic left ventricular heart failure. In this study, we aimed to examine if angiotensin receptor‐neprilysin inhibition using sac/val attenuates RV remodeling in PH.

Methods and Results

RV pressure overload was induced in Sprague–Dawley rats via banding the main pulmonary artery. Three different cohorts of controls, placebo‐treated PH, and sac/val‐treated PH were studied in a 21‐day treatment window. Terminal invasive hemodynamic measurements, quantitative histological analysis, biaxial mechanical testing, and constitutive modeling were employed to conduct a multiscale analysis on the effects of sac/val on RV remodeling in PH. Sac/val treatment decreased RV maximum pressures (29% improvement, P=0.002), improved RV contractile (30%, P=0.012) and relaxation (29%, P=0.043) functions, reduced RV afterload (35% improvement, P=0.016), and prevented RV‐pulmonary artery uncoupling. Furthermore, sac/val attenuated RV hypertrophy (16% improvement, P=0.006) and prevented transmural reorientation of RV collagen and myofibers (P=0.011). The combined natriuresis and vasodilation resulting from sac/val led to improved RV biomechanical properties and prevented increased myofiber stiffness in PH (61% improvement, P=0.032).

Conclusions

Sac/val may prevent maladaptive RV remodeling in a pressure overload model via amelioration of RV pressure rise, hypertrophy, collagen, and myofiber reorientation as well as tissue stiffening both at the tissue and myofiber level.

Dual Angiotensin Receptor and Neprilysin Inhibitor Ameliorates Portal Hypertension in Portal Hypertensive Rats

BACKGROUND

Portal hypertension is characterized by exaggerated activation of the renin-angiotensin-aldosterone axis. Natriuretic peptide system plays a counter-regulatory role, which is modulated by neprilysin. LCZ696 (sacubitril/valsartan) is a dual angiotensin receptor and neprilysin inhibitor. This study evaluated the effect of LCZ696 on portal hypertensive rats.

METHODS

Portal hypertension was induced by partial portal vein ligation (PVL) in rats. LCZ696, valsartan (angiotensin receptor blocker), or normal saline (control) was administered in PVL rats for 10 days. Then, hemodynamic and biochemistry data were obtained. The hepatic histology and protein expressions were surveyed. On the parallel groups, the portal-systemic shunting degrees were determined.

RESULTS

LCZ696 and valsartan reduced mean arterial pressure and systemic vascular resistance. LCZ696, but not valsartan, reduced portal pressure in portal hypertensive rats (control vs. valsartan vs. LCZ696: 15.4 ± 1.6 vs. 14.0 ± 2.3 vs. 12.0 ± 2.0 mmHg, control vs. LCZ696: P < 0.05). LCZ696 and valsartan improved liver biochemistry data and reduced intrahepatic Cluster of Differentiation 68 (CD68)-stained macrophages infiltration. Hepatic endothelin-1 (ET-1) protein expression was downregulated by LCZ696. The portal-systemic shunting was not affected by LCZ696 and valsartan.

CONCLUSION

LCZ696 and valsartan reduced mean arterial pressure through peripheral vasodilation. Furthermore, LCZ696 significantly reduced portal pressure in PVL rats via hepatic ET-1 downregulation.

Skeletal muscle alterations in tachycardia-induced heart failure are linked to deficient natriuretic peptide signalling and are attenuated by RAS-/NEP-inhibition

Background

Heart failure induced cachexia is highly prevalent. Insights into disease progression are lacking.

Methods

Early state of left ventricular dysfunction (ELVD) and symptomatic systolic heart failure (HF) were both induced in rabbits by tachypacing. Tissue of limb muscle (LM) was subjected to histologic assessment. For unbiased characterisation of early and late myopathy, a proteomic approach followed by computational pathway-analyses was performed and combined with pathway-focused gene expression analyses. Specimen of thoracic diaphragm (TD) served as control for inactivity-induced skeletal muscle alterations. In a subsequent study, inhibition of the renin-angiotensin-system and neprilysin (RAS-/NEP) was compared to placebo.

Results

HF was accompanied by loss of protein content (8.7±0.4% vs. 7.0±0.5%, mean±SEM, control vs. HF, p<0.01) and a slow-to-fast fibre type switch, establishing hallmarks of cachexia. In ELVD, the enzymatic set-up of LM and TD shifted to a catabolic state. A disturbed malate-aspartate shuttle went well with increased enzymes of glycolysis, forming the enzymatic basis for enforced anoxic energy regeneration. The histological findings and the pathway analysis of metabolic results drew the picture of suppressed PGC-1α signalling, linked to the natriuretic peptide system. In HF, natriuretic peptide signalling was desensitised, as confirmed by an increase in the ratio of serum BNP to tissue cGMP (57.0±18.6pg/ml/nM/ml vs. 165.8±16.76pg/ml/nM/ml, p<0.05) and a reduced expression of natriuretic peptide receptor-A. In HF, combined RAS-/NEP-inhibition prevented from loss in protein content (8.7±0.3% vs. 6.0±0.6% vs. 8.3±0.9%, Baseline vs. HF-Placebo vs. HF-RAS/NEP, p<0.05 Baseline vs. HF-Placebo, p = 0.7 Baseline vs. HF-RAS/NEP).

Conclusions

Tachypacing-induced heart failure entails a generalised myopathy, preceding systolic dysfunction. The characterisation of “pre-cachectic” state and its progression is feasible. Early enzymatic alterations of LM depict a catabolic state, rendering LM prone to futile substrate metabolism. A combined RAS-/NEP-inhibition ameliorates cardiac-induced myopathy independent of systolic function, which could be linked to stabilised natriuretic peptide/cGMP/PGC-1α signalling.

Sacubitril/valsartan effect on left ventricular remodeling: the case of a super-responder

Sacubitril/valsartan has been shown to improve clinical outcomes in patients with heart failure and reduced ejection fraction (HFrEF), but its effects on left ventricular (LV) systolic function and reverse remodeling parameters remain to be established. We hereby describe the case of a 41 year old man with HFrEF and severe reduction of left ventricular ejection fraction (LVEF). The patient was first treated with triple HF therapy (beta-blocker, angiotensin converting enzyme inhibitor and mineralocorticoid antagonist), but after three months he was still symptomatic and with an LVEF firmly low. In consideration of poor response to therapy, we switched angiotensin converting enzyme inhibitor to sacubitril/valsartan to the maximum tolerated dose (49/51 mg bid) with a marked improvement in LV systolic function and reduction in LV volumes at follow-up. In light of the almost normalized LVEF the patient was also removed from the list for the implantation of a cardiac resynchronization therapy defibrillator. In conclusion, our case showed a strong beneficial effect of sacubitril/valsartan on reverse remodeling and LVEF beyond the benefits of concomitant optimal medical therapy. This result is particular noteworthy because it was obtained although the patient wasn't able to reach the full dose of the drug. Physicians should always consider this drug effect when more demanding therapeutic strategies are needed for their HF patients.

Efficacy of Angiotensin Converting Enzyme Inhibitors and Angiotensin Receptor-Neprilysin Inhibitors in the Treatment of Chronic Heart Failure: A Review of Landmark Trials

Heart failure (HF) is a multi-faceted clinical condition affecting up to 2% of the population in the developed world and is linked to significant morbidity and mortality, therefore posing a major public health concern. To this date, pharmacotherapy for HF has mainly focused on chronic HF with reduced ejection fraction (HFrEF), with angiotensin converting enzyme inhibitors (ACEi) being at the centre of the management plan, alongside angiotensin-receptor-blockers (ARBs), β-blockers (BB) and mineralocorticoid receptor antagonists (MRAs). A novel and recently approved therapy, however, involving angiotensin receptor-neprilysin inhibitors (ARNI), has shown very promising results and comparable to those of ACEi, which raises the question of whether ACEi should remain the first-line treatment option for HFrEF. In this review, the evidence regarding the clinical efficacy of ACEi and ARNI in the treatment of HFrEF is discussed, with emphasis placed on the major landmark trials.

The renin-angiotensin system in cardiovascular autonomic control: recent developments and clinical implications

Complex and bidirectional interactions between the renin-angiotensin system (RAS) and autonomic nervous system have been well established for cardiovascular regulation under both physiological and pathophysiological conditions. Most research to date has focused on deleterious effects of components of the vasoconstrictor arm of the RAS on cardiovascular autonomic control, such as renin, angiotensin II, and aldosterone. The recent discovery of prorenin and the prorenin receptor have further increased our understanding of RAS interactions in autonomic brain regions. Therapies targeting these RAS components, such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers, are commonly used for treatment of hypertension and cardiovascular diseases, with blood pressure-lowering effects attributed in part to sympathetic inhibition and parasympathetic facilitation. In addition, a vasodilatory arm of the RAS has emerged that includes angiotensin-(1-7), ACE2, and alamandine, and promotes beneficial effects on blood pressure in part by reducing sympathetic activity and improving arterial baroreceptor reflex function in animal models. The role of the vasodilatory arm of the RAS in cardiovascular autonomic regulation in clinical populations, however, has yet to be determined. This review will summarize recent developments in autonomic mechanisms involved in the effects of the RAS on cardiovascular regulation, with a focus on newly discovered pathways and therapeutic targets for this hormone system.

Significance of non-coding circular RNAs and micro RNAs in the pathogenesis of cardiovascular diseases

Heart failure, coronary artery disease and myocardial infarction are the most prominent cardiovascular diseases contributing significantly to death worldwide. In the majority of situations, except for surgical interventions and transplantation, there are no reliable therapeutic approaches available to address these health problem. Despite several advances that led to the development of biomarkers and therapies based on the renin–angiotensin system, adrenergic pathways, etc, more definitive and consistent biomarkers and specific target based molecular therapies are still being sought. Recent advances in the field of genomic research has helped in identifying non-coding RNAs, including circular RNAs, piRNAs, micro RNAs, and long non-coding RNAs, that play a significant role in the regulation of gene expression and function and have direct impact on pathophysiological mechanisms. This new knowledge is currently being explored with much hope for the development of novel treatments and biomarkers. Circular RNAs and micro RNAs have been described in myocardium and aortic valves and were shown to be involved in the regulation of pathophysiological processes that potentially contribute to cardiovascular diseases. Approximately 32 000 human exonic circular RNAs have been catalogued and their functions are still being ascertained. In the heart, circular RNAs were shown to bind micro RNAs in a specific manner and regulate the expression of transcription factors and stress response genes, and expression of these non-coding RNAs were found to change in conditions such as cardiac hypertrophy, heart failure and cardiac remodelling, reflecting their significance as diagnostic and prognostic biomarkers. In this review, we address the present state of understanding on the biogenesis, regulation and pathophysiological roles of micro and circular RNAs in cardiovascular diseases, and on the potential future perspectives on their use as biomarkers and therapeutic agents.

A Narrative Review of Persistent Post-Stroke Headache - A New Entry in the International Classification of Headache Disorders, 3rd Edition

BACKGROUND

Persistent post-stroke headache is a clinical entity that has recently entered the International Classification of Headache Disorders, 3rd edition. In contrast to acute headache attributed to stroke, the epidemiology, clinical features, potential pathophysiology, and management of persistent post-stroke headache have not been reviewed.

METHODS

We summarize the literature describing persistent headache attributed to stroke.

RESULTS

Persistent headache after ischemic or hemorrhagic stroke affects up to 23% of patients. These persistent headaches tend to have tension-type features and are more frequent and severe than acute stroke-related headaches. Risk factors include younger age, female sex, pre-existing headache disorder, and comorbid post-stroke fatigue or depression. Other factors including obstructive sleep apnea or musculoskeletal imbalances may contribute to headache persistence. Although more evidence is needed, it may be reasonable to treat persistent post-stroke headache according to headache semiology.

CONCLUSION

Recognition of persistent post-stroke headache as a separate clinical entity from acute stroke-attributed headache is the first step toward better defining its natural history and most effective treatment strategies.

Next-generation small molecule therapies for heart failure: 2015 and beyond

Poor prognosis coupled with significant economic burden makes heart failure (HF) one of the largest issues currently facing the world population. Although a significant number of new therapies have emerged over the past 20 years to treat the underlying physiological risk factors, only two new medications specifically for HF have been approved since 2007. This perspective provides an overview of recently approved treatment options for HF and as well as an update on additional small molecule therapies currently in clinical development.