The Cardiorenal Effects of Chronic Phosphodiesterase-V Inhibition in Preclinical Diastolic Dysfunction (Stage B Heart Failure).

OBJECTIVE: To determine whether chronic phosphodiesterase-V (PDEV) inhibition with tadalafil will improve urinary sodium excretion, glomerular filtration rate (GFR), plasma cyclic guanosine 3', 5'-monophosphate (cGMP), and urinary cGMP excretion in response to volume expansion (VE) in patients with preclinical diastolic dysfunction (PDD) or stage B heart failure. BACKGROUND: PDD is defined as abnormal diastolic function with normal systolic function, without clinical heart failure. PDD is predictive of development of heart failure and all-cause mortality. Impaired renal function and attenuated cGMP response to VE are hallmarks of PDD. METHODS: A double-blind, placebo-controlled, proof-of-concept study was conducted to compare 12 weeks of tadalafil 20 mg daily (n = 14) vs placebo (n = 7). Subjects underwent 2 study visits 12 weeks apart. Renal, neurohormonal and echocardiographic assessments were performed before and after intravascular VE (normal saline 0.25 mL/kg/min for 1 hour). RESULTS: Baseline characteristics were similar. There was no increase in GFR, plasma cGMP or urinary cGMP excretion in response to VE in either group at visit 1. At visit 2, tadalafil did not result in significant change in GFR but increased plasma cGMP and urinary cGMP excretion at baseline. In response to VE, tadalafil resulted in increased urine flow, urinary sodium excretion, GFR (7.00 [-1.0, 26.3] vs -9.00 [-24.5, 2.0] mL/min/1.73m2; P = 0.02) and plasma cGMP (0.50 [-0.1, 0.7] vs -0.25 [-0.6, -0.1] pmol/mL; P = 0.02). It did not improve urinary cGMP excretion after VE. CONCLUSION: In PDD, chronic PDEV inhibition with tadalafil improved renal response to VE through increased urine flow, urinary sodium excretion, GFR, and plasma cGMP. Further studies are required to determine whether this enhanced renal response can mitigate progression to clinical heart failure.

Evidence for Angiotensin II as a Naturally Existing Suppressor for the Guanylyl Cyclase A Receptor and Cyclic GMP Generation.

The natriuretic peptide system (NPS) and renin-angiotensin-aldosterone system (RAAS) function oppositely at multiple levels. While it has long been suspected that angiotensin II (ANGII) may directly suppress NPS activity, no clear evidence to date supports this notion. This study was designed to systematically investigate ANGII-NPS interaction in humans, in vivo, and in vitro. Circulating atrial, b-type, and c-type natriuretic peptides (ANP, BNP, CNP), cyclic guanosine monophosphate (cGMP), and ANGII were simultaneously investigated in 128 human subjects. Prompted hypothesis was validated in vivo to determine the influence of ANGII on ANP actions. The underlying mechanisms were further explored via in vitro approaches. In humans, ANGII demonstrated an inverse relationship with ANP, BNP, and cGMP. In regression models predicting cGMP, adding ANGII levels and the interaction term between ANGII and natriuretic peptides increased the predictive accuracy of the base models constructed with either ANP or BNP, but not CNP. Importantly, stratified correlation analysis further revealed a positive association between cGMP and ANP or BNP only in subjects with low, but not high, ANGII levels. In rats, co-infusion of ANGII even at a physiological dose attenuated cGMP generation mediated by ANP infusion. In vitro, we found the suppressive effect of ANGII on ANP-stimulated cGMP requires the presence of ANGII type-1 (AT1) receptor and mechanistically involves protein kinase C (PKC), as this suppression can be substantially rescued by either valsartan (AT1 blocker) or Go6983 (PKC inhibitor). Using surface plasmon resonance (SPR), we showed ANGII has low binding affinity to the guanylyl cyclase A (GC-A) receptor compared to ANP or BNP. Our study reveals ANGII is a natural suppressor for the cGMP-generating action of GC-A via AT1/PKC dependent manner and highlights the importance of dual-targeting RAAS and NPS in maximizing beneficial properties of natriuretic peptides in cardiovascular protection.

EVIDENCE FOR ANGIOTENSIN II AS A NATURALLY EXISTING SUPPRESSOR FOR THE NATRIURETIC PEPTIDE SYSTEM.

Background: Natriuretic peptide system (NPS) and renin angiotensin aldosterone system (RAAS) function oppositely at multiple levels. While it has long been suspected that angiotensin II (ANGII) may directly suppress NPS activity, no clear evidence to date support this notion. Objectives: This study was designed to systematically investigate ANGII-NPS interaction in humans, in vivo, and in vitro for translational insights. Methods: Circulating atrial, b-type, and c-type natriuretic peptides (ANP, BNP, CNP), cyclic guanosine monophosphate (cGMP), and ANGII were simultaneously investigated in 128 human subjects. Prompted hypothesis was validated in rat model to determine influence of ANGII on ANP actions. Multiple engineered HEK293 cells and surface plasmon resonance (SPR) technology were leveraged for mechanistic exploration. Results: In humans, ANGII showed inverse relationship with ANP, BNP, and cGMP. In regression models predicting cGMP, adding ANGII levels and interaction term between ANGII and natriuretic peptide increased predicting accuracy of base models constructed with either ANP or BNP, but not CNP. Importantly, stratified correlation analysis further revealed positive association between cGMP with ANP or BNP only in subjects with low, but not high, ANGII levels. In rats, co-infusion of ANGII even at physiological dose attenuated blood pressure reduction and cGMP generation triggered by ANP infusion. In vitro, we showed that the suppression effect of ANGII on ANP-stimulated cGMP requires the presence of ANGII type-1 (AT1) receptor and mechanistically involves protein kinase C (PKC), which can be substantially rescued by either valsartan (AT1 blocker) or Go6983 (PKC inhibitor). Using SPR, we showed ANGII has low affinity for particulate guanylyl cyclase A (GC-A) receptor binding compared to ANP or BNP. Conclusions: Our study reveals ANGII as a natural suppressor for cGMP-generating action of GC-A via AT1/PKC dependent manner and highlights importance of dual-targeting RAAS and NPS in maximizing beneficial properties of natriuretic peptides in cardiovascular disease.

Natriuretic peptide pathways in heart failure: further therapeutic possibilities.

The discovery of the heart as an endocrine organ resulted in a remarkable recognition of the natriuretic peptide system (NPS). Specifically, research has established the production of atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) from the heart, which exert pleiotropic cardiovascular, endocrine, renal, and metabolic actions via the particulate guanylyl cyclase A receptor (GC-A) and the second messenger, cGMP. C-type natriuretic peptide (CNP) is produced in the endothelium and kidney and mediates important protective auto/paracrine actions via GC-B and cGMP. These actions, in part, participate in the efficacy of sacubitril/valsartan in heart failure (HF) due to the augmentation of the NPS. Here, we will review important insights into the biology of the NPS, the role of precision medicine, and focus on the phenotypes of human genetic variants of ANP and BNP in the general population and the relevance to HF. We will also provide an update of the existence of NP deficiency states, including in HF, which provide the rationale for further therapeutics for the NPS. Finally, we will review the field of peptide engineering and the development of novel designer NPs for the treatment of HF. Notably, the recent discovery of a first-in-class small molecule GC-A enhancer, which is orally deliverable, will be highlighted. These innovative designer NPs and small molecule possess enhanced and novel properties for the treatment of HF and cardiovascular diseases.

Assessing intrinsic renal sodium avidity in acute heart failure: implications in predicting and guiding decongestion.

AIM: Intrinsic renal sodium avidity (IRSA) is a hallmark feature of acute heart failure (AHF) and can be measured by evaluating the urinary sodium (UNa) concentration. The aim of this study is to assess the role of measuring IRSA through a random Una-sample and its association with decongestive response. METHODS AND RESULTS: A post-hoc analysis of the ROSE-AHF trial was performed in all patients with a random UNa spot sample before randomization (n = 339/360). Patients were categorized according to tertiles of UNa as high (range 19-40 mmol/L), intermediate (range 41-68 mmol/L), or low (range 69-139 mmol/L) IRSA. Linear mixed effect models and ANCOVA were used to assess the relation with decongestive effectiveness measured by: (i) weight change, (ii) visual analogue scale (VAS) improvement, (iii) N-terminal pro-B-type natriuretic peptide (NT-proBNP) change, (iv) natriuretic response (UNa in mmol/L), (v) 72 h natriuresis (mmol), (vi) oedema resolution, and (vii) length of stay. High IRSA patients had less improvement in decongestive metrics, including weight loss (p = 0.028), VAS improvement, NT-proBNP decrease, natriuretic response (p-time interaction <0.001 for all), had lower total natriuresis (high IRSA 438 ± 141 mmol, intermediate IRSA 526 ± 320 mmol, and low IRSA 603 ± 276 mmol; p < 0.001), exhibited more oedema at 72 h (p = 0.005), and had a longer length of stay (p = 0.015). Incremental loop diuretic dose titration (± 4 times home dose) after >24 h, resulted in an increase in natriuretic response in the high IRSA group, however cumulative natriuresis still remained lower at 72 h (p < 0.001). Longitudinal UNa profiling of patients with low IRSA showed physiologic breaking in the UNa pattern, associated with attaining decongestion and slight increase in creatinine and cystatin C, forming a potential signal of complete decongestion. CONCLUSIONS: A simple random UNa sample at the time of AHF, gives insight into IRSA which is consistently associated with decongestive effectiveness across multiple metrics, offering an opportunity for early AHF care improvement.

Incidence of Preclinical Heart Failure in a Community Population.

Background A high prevalence of preclinical heart failure (HF) (Stages A and B) has previously been shown. The aim of this study was to explore factors associated with the incidence of preclinical HF in a community population. Methods and Results Retrospective review of 393 healthy community individuals aged ≥45 years from the Olmsted County Heart Function Study that returned for 2 visits, 4 years apart. At visit 2, individuals that remained normal were compared with those that developed preclinical HF. By the second visit, 191 (49%) developed preclinical HF (12.1 cases per 100 person-years of follow-up); 65 (34%) Stage A and 126 (66%) Stage B. Those that developed preclinical HF (n=191) were older (P=0.004), had a higher body mass index (P<0.001), and increased left ventricular mass index (P=0.006). When evaluated separately, increased body mass index was seen with development of Stage A (P<0.001) or Stage B (P=0.009). Echocardiographic markers of diastolic function were statistically different in those that developed Stage A [higher E/e' (P<0.001), lower e' (P<0.001)] and Stage B [higher left atrial volume index (P<0.001), higher E/e' (P<0.001), lower e' (P<0.001)]. NT-proBNP (N-terminal pro-B-type natriuretic peptide) was higher at visit 2 in those that developed Stage A or B (P<0.001 for both). Hypertension (57%), obesity (34%), and hyperlipidemia (25%) were common in the development of Stage A. Of patients who developed Stage B, 71% (n=84) had moderate or severe diastolic dysfunction. Conclusions There is a high incidence of preclinical HF in a community population. Development of Stage A was driven by hypertension and obesity, while preclinical diastolic dysfunction was seen commonly in those that developed Stage B.

Insulin Therapy is Associated With Increased Myocardial Interstitial Fibrosis and Cardiomyocyte Apoptosis in a Rodent Model of Experimental Diabetes.

The incidence of diabetes mellitus (DM) is rising. DM is a risk factor for developing left ventricular (LV) dysfunction and adverse cardiovascular outcomes. Insulin, commonly used to treat DM, is associated with further worsening of such outcomes. Yet, the pathophysiology of the adverse properties of insulin on the heart remains poorly defined. Therefore, the objective of this study was to determine the biological effects of insulin on the heart in DM, which we tested in vivo in a diabetic rat model and in vitro on human cardiomyocytes and fibroblasts. Male Wistar rats were divided into 3 groups: controls (n = 17), untreated diabetics (UDM, n = 15), and insulin-treated diabetics (IDM, n = 9). Diabetes was induced with Streptozotocin. Insulin pumps in IDM and saline pumps in UDM and controls were implanted for 4 weeks before tissue collection. Separately, cultures of human cardiomyocytes (AC16) and human cardiac fibroblasts (HCF) were treated with insulin to assess apoptosis and fibrosis, respectively. In rats, insulin partially rescued the DM-associated weight loss while fully restoring euglycemia. However, IDM had 2 × the rate of LV fibrosis (p < 0.0001) compared to UDM, and triple the rate of cardiomyocyte apoptosis compared to controls (p < 0.05). Similarly, in vitro, insulin triggered apoptosis in a dose-dependent fashion in AC16 cells, and it increased fibrosis and upregulated SMAD2 in HCF to levels comparable to Transforming Growth Factor Beta 1. Therefore, we conclude that insulin therapy is associated with increased cardiomyocyte apoptosis and myocardial interstitial fibrosis. Longer studies are needed to explore the long-term effects of insulin on cardiac structure and function.

Cardiorenal Effects of Long-Term Phosphodiesterase V Inhibition in Pre-Heart Failure.

Background Phosphodiesterase V (PDEV) is upregulated in heart failure, leading to increased degradation of cGMP and impaired natriuresis. PDEV inhibition improves the renal response to B-type natriuretic peptide in animal models. We tested the hypothesis that long-term PDEV inhibition would improve renal function and cardiorenal response after short-term volume load in subjects with pre-heart failure. Methods and Results A total of 20 subjects with pre-heart failure (defined as an ejection fraction ≤45% without previous diagnosis of heart failure) and renal impairment were randomized in a 2:1 manner to tadalafil or placebo. Baseline echocardiography and renal clearance study were performed, followed by a short-term saline load and repeated echocardiography and renal clearance study. Subjects then received either tadalafil at a goal dose of 20 mg daily or placebo, and the study day was repeated after 12 weeks. Long-term tadalafil did not improve glomerular filtration rate (median increase of 2.0 mL/min in the tadalafil group versus 13.5 mL/min in the placebo group; P=0.54). There was no difference in urinary sodium or cGMP excretion with PDEV inhibition following short-term saline loading. Conclusions Glomerular filtration rate and urinary sodium/cGMP excretion were not significantly different after 12 weeks of tadalafil compared with placebo. These results do not support the use of PDEV inhibition to improve renal response in patients with pre-heart failure. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01970176.

MANP (M-Atrial Natriuretic Peptide) Reduces Blood Pressure and Furosemide-Induced Increase in Aldosterone in Hypertension.

BACKGROUND: cGMP MANP (M-atrial natriuretic peptide) is a best-in-class activator of the pGC-A (particulate guanylyl cyclase A) receptor. Furosemide increases the effectiveness of antihypertensive agents, but activates renin-angiotensin-aldosterone system. We aimed to investigate for the first time cardiorenal and neurohumoral actions of MANP in a genetic model of hypertension in spontaneously hypertensive rats. We also assessed how MANP would potentiate the blood pressure (BP)-lowering actions of furosemide while reducing the production of aldosterone. METHODS: Spontaneously hypertensive rats (N=60) were randomized in vehicle, MANP, furosemide, or MANP+furosemide groups. Furosemide (1, 5, 10 mg/kg) was given as a single bolus which in MANP+furosemide groups was followed by a 60-minute infusion of MANP. RESULTS: BP was reduced in MANP300 (300 pmol/[kg·min]) and MANP600 (600 pmol/[kg·min]) groups (P<0.05) and was accompanied by significant increase in plasma cyclic guanosine monophosphate. Furosemide alone reduced BP but less compared with MANP with no change in plasma cyclic guanosine monophosphate. MANP+furosemide resulted in the greatest BP reduction and significant increase in plasma cyclic guanosine monophosphate in Fs5+MANP300, Fs10+MANP300, and Fs10+MANP600. Plasma aldosterone increased in furosemide groups, which was significantly attenuated in MANP+furosemide groups. Natriuresis and diuresis increased in all treated groups (P<0.05) with no significant differences between furosemide and furosemide+MANP. In vitro, MANP increased cyclic guanosine monophosphate level in human vascular cells. CONCLUSIONS: We provide novel evidence that MANP potentiates the BP-lowering actions of furosemide, suppresses the activation of renin-angiotensin-aldosterone system, and preserves renal function. These data are highly relevant to clinical needs in the treatment of hypertension and heart failure.

Outcomes of Patients With Diabetes Versus Patients Without Diabetes Hospitalized With Acute Heart Failure.

The objective is to define the clinical echocardiographic characteristics and cardiovascular outcome in patients with acute heart failure (HF) with versus without diabetes mellitus (DM). Demographic, clinical, laboratory, and echocardiographic data were collected in Olmsted County adults hospitalized for acute HF between 2005 and 2008. Analyses were performed for mortality and acute HF hospitalization outcomes stratified by diabetic status, systolic function, and diastolic function. There were 912 subjects who met inclusion criteria, and mean age was 79 (SD 13.1) years with 53% women. Prevalence of DM was 42% in the study population, and those with DM had worse diastolic function and increased mortality and HF rehospitalization. Among those with DM and acute HF, reduced left ventricular ejection fraction and worse diastolic function conferred increased HF rehospitalization (p = 0.010 and p = 0.022, respectively). In conclusion, DM is common in those hospitalized for acute HF and is associated with worse long-term clinical outcomes. The subgroup of DM with acute HF and left ventricular systolic dysfunction or diastolic dysfunction had worse HF rehospitalization outcomes.

First-in-Human Study of MANP: A Novel ANP (Atrial Natriuretic Peptide) Analog in Human Hypertension.

[Figure: see text].

Effects of phosphodiesterase V inhibition alone and in combination with BNP on cardiovascular and renal response to volume load in human preclinical diastolic dysfunction.

Preclinical diastolic dysfunction (PDD) results in impaired cardiorenal response to volume load (VL) which may contribute to the progression to clinical heart failure with preserved ejection fraction (HFpEF). The objective was to evaluate if phosphodiesterase V inhibition (PDEVI) alone or combination PDEVI plus B-type natriuretic peptide (BNP) administration will correct the impaired cardiorenal response to VL in PDD. A randomized double-blinded placebo-controlled cross-over study was conducted in 20 subjects with PDD, defined as left ventricular ejection fraction (LVEF) >50% with moderate or severe diastolic dysfunction by Doppler echocardiography and without HF diagnosis or symptoms. Effects of PDEVI with oral tadalafil alone and tadalafil plus subcutaneous (SC) BNP, administered prior to acute volume loading, were assessed. Tadalafil alone did not result in improvement in cardiac response to VL, as measured by LVEF, LV end diastolic volume, left atrial volume (LAV), or right ventricular systolic pressure (RVSP). Tadalafil plus SC BNP resulted in improved cardiac response to VL, with increased LVEF (4.1 vs. 1.8%, p = 0.08) and heart rate (4.3 vs. 1.6 bpm, p = 0.08), and reductions in both LAV (-4.3 ± 10.4 vs. 2.8 ± 6.6 ml, p = 0.03) and RVSP (-4.0 ± 3.0 vs. 2.1 ± 6.0 mmHg, p < 0.01) versus tadalafil alone. Plasma and urinary cyclic guanosine monophosphate (cGMP) excretion levels were higher (11.3 ± 12.3 vs. 1.7 ± 3.8 pmol/ml, 1851.0 ± 1386.4 vs. 173.4 ± 517.9 pmol/min, p < 0.01) with tadalafil plus SC BNP versus tadalafil alone. There was no improvement in renal response as measured by GFR, renal plasma flow, sodium excretion, and urine flow with tadalafil plus SC BNP compared to tadalafil alone. In subjects with PDD, tadalafil alone resulted in no improvement in cardiac adaptation, while tadalafil and SC BNP resulted in enhanced cardiac adaptation to VL. TRIAL REGISTRATION: ClinicalTrials.gov NCT01544998.

Prognostic Value of Urinary and Plasma C-Type Natriuretic Peptide in Acute Decompensated Heart Failure.

OBJECTIVES: This study sought to characterize urinary and plasma C-type natriuretic peptide (CNP) in acute decompensated heart failure (ADHF) to define their relationship with clinical variables and to determine whether urinary and plasma CNP together add prognostic value. BACKGROUND: CNP is a protective hormone that is synthesized in the kidney and endothelium and possesses antiremodeling properties. Urinary and plasma CNP levels are elevated in pathophysiological conditions; however, their regulation and prognostic value in heart failure (HF) is unclear. METHODS: Urinary and plasma CNP were measured in 109 healthy subjects and 208 patients with ADHF; the 95th percentile of CNP values from healthy subjects established the normal contemporary cutoffs. Patients with ADHF were stratified based on urinary and plasma CNP levels for clinical characterization and the assessment of risk for adverse outcomes. RESULTS: There was no significant correlation between urinary and plasma CNP in both cohorts. Urinary and plasma CNP were significantly elevated in patients with ADHF, and both increased with disease severity and were positively correlated with plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP). Of the patients with ADHF, 23% had elevations in both urinary and plasma CNP, whereas 24% had normal CNP levels. During a median follow-up of 3 years, patients with elevated urinary and plasma CNP had a significantly higher risk of rehospitalization and/or death (HR: 1.79; P = 0.03) and rehospitalization (HR: 2.16; P = 0.01) after adjusting for age, sex, left ventricular ejection fraction, renal function, and plasma NT-proBNP. The C-statistic and integrated discrimination analyses further supported that the addition of urinary and plasma CNP to established risk models improved the prediction of adverse outcomes in patients with ADHF. CONCLUSIONS: Urinary and plasma CNP are differentially regulated in ADHF, and elevations in both provided independent prognostic value for predicting adverse outcomes.

Progression of Preclinical Heart Failure: A Description of Stage A and B Heart Failure in a Community Population.

BACKGROUND: The aims of this study are to evaluate the rate of progression of preclinical (Stage A and B) heart failure, identify associated characteristics, and evaluate long-term outcomes. METHODS: Retrospective review of the Olmsted County Heart Function Study. Individuals categorized as Stage A or B heart failure at initial visit that returned for a second visit 4 years later were included. Logistic regression analyses evaluated group differences with adjustment for age and sex. RESULTS: At visit 1, 413 (32%) individuals were classified as Stage A and 413 (32%) as Stage B. By visit 2, 146 (35%) individuals from Stage A progressed with the vast majority (n=142) progressing to Stage B. In comparison, a total of 23 (6%) individuals progressed from Stage B. A greater rate of progression was seen for Stage A compared with Stage B (8.7 per 100 person-years [95% CI, 7.4-10.2] versus 1.4 per 100 person-years [95% CI, 0.9-2.1]; P<0.001). NT-proBNP correlated with progression for Stage B (P=0.01), but not for Stage A (P=0.39). A multivariate model found female sex (odds ratio, 1.65 [95% CI, 1.05-2.58]; P=0.03), increased E/e' (odds ratio, 1.13 [95% CI, 1.02-1.26], P=0.02), and beta blocker use (odds ratio, 2.19 [95% CI, 1.25-3.82], P=0.006) were associated with progression for Stage A. There was a signal that cardiovascular mortality was higher in individuals who progressed, although not statistically significant (P=0.06 for Stage A and P=0.05 for Stage B). CONCLUSIONS: There is significant progression of preclinical heart failure in a community population, with progression rates higher for Stage A. NT-proBNP correlated with progression for Stage B, but not for Stage A. No statistically significant differences in long-term outcomes were seen. Study results have clinical implications important to help guide future heart failure screening and prevention strategies.

Implications of peripheral oedema in heart failure with preserved ejection fraction: a heart failure network analysis.

AIMS: Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous condition, and tissue congestion manifested by oedema is not present in all patients. We compared clinical characteristics, exercise capacity, and outcomes in patients with HFpEF with and without oedema. METHODS AND RESULTS: This study was a post hoc analysis of pooled data of patients with left ventricular ejection fraction of ≥50% enrolled in the DOSE, CARRESS-HF, RELAX, ATHENA, ROSE, INDIE, and NEAT trials. Patients were dichotomized by the severity of oedema. Cox proportional hazard regression and generalized linear regression models were used to assess associations between oedema, symptoms, and clinical outcomes. The ambulatory cohort included 393 patients (228 with and 165 without oedema), and the hospitalized cohort included 338 patients (249 with ≥moderate oedema and 89 with mild or none). Among ambulatory patients, patients with oedema had a higher body mass index (35.2 kg/m2 [inter-quartile range, IQR 30.5, 41.6] vs. 31.6 kg/m2 [IQR 27.9, 36.3], P < 0.001), greater burden of co-morbidities, higher intravascular pressures estimated on physical examination (elevated jugular venous pressure: 50% vs. 24.7%, P < 0.001), poorer renal function (creatinine: 1.2 mg/dL [IQR 0.9, 1.5] vs. 1 mg/dL [IQR 0.8, 1.3], P = 0.003), and lower peak VO2 (adjusted mean difference -1.04 mL/kg/min, 95% confidence interval [-1.71, -0.37], P < 0.003). Among hospitalized patients, despite greater in-hospital fluid/weight loss in the ≥moderate oedema group, there was no difference in the improvement in dyspnoea by the visual analogue scale or well-being visual analogue scale from baseline to 3-4 days and no statistically significant difference in the rate of 60 day rehospitalization/death (adjusted hazard ratio 1.44, 95% confidence interval [0.87, 2.39], P = 0.156). CONCLUSIONS: Patients with HFpEF and oedema display higher body mass, greater burden of co-morbidities, and more severe exercise intolerance, but clinical responses to treatment appear similar. Further research is required to better understand the nature of volume distribution in different HFpEF phenotypes.

B-type natriuretic peptide and cardiac remodelling after myocardial infarction: a randomised trial.

OBJECTIVE: B-type natriuretic peptide (BNP) has favourable effects on left ventricular remodelling, including antifibrotic and antiapoptotic properties. We tested the hypothesis that infusion of BNP after an acute myocardial infarction would reduce left ventricular systolic and diastolic volumes and improve left ventricular ejection fraction compared with placebo. METHODS: A total of 58 patients who underwent successful revascularisation for an acute ST elevation anterior myocardial infarction were randomised to receive 72-hour infusion of BNP at 0.006 µg/kg/min or placebo. Left ventricular end diastolic and systolic volumes and left ventricular ejection fraction were measured at baseline and at 30 days by multigated acquisition scan. Left ventricular infarction size was measured by cardiac MRI. RESULTS: BNP infusion led to significantly higher BNP levels and plasma cyclic guanosine monophosphate at 72 hours. No significant difference in change of left ventricular volumes or ejection fraction from baseline to 30 days was observed between groups. Although left ventricular infarction size measured by cardiac MRI was not significantly different between BNP infusion versus placebo (p=0.39), there was a trend towards reduced infarction size in patients with a baseline ejection fraction of <40% (p=0.14). CONCLUSIONS: Infusion of BNP in patients with an anterior myocardial infarction did not affect parameters of left ventricular remodelling. Patients treated with BNP who had a baseline left ventricular ejection fraction of <40% had a trend towards reduced left ventricular infarction size compared with placebo. These results do not support the use of intravenous BNP in patients after recent myocardial infarction. TRIAL REGISTRATION NUMBER: NCT00573144.

The Importance of Natriuretic Peptides in Cardiometabolic Diseases.

The natriuretic peptide (NP) system is composed of 3 distinct peptides (atrial natriuretic peptide or ANP, B-type natriuretic peptide or BNP, and C-type natriuretic peptide or CNP) and 3 receptors (natriuretic peptide receptor-A or NPR-A or particulate guanynyl cyclase-A natriuretic peptide receptor-B or NPR-B or particulate guanynyl cyclase-B, and natriuretic peptide receptor-C or NPR-C or clearance receptor). ANP and BNP function as defense mechanisms against ventricular stress and the deleterious effects of volume and pressure overload on the heart. Although the role of NPs in cardiovascular homeostasis has been extensively studied and well established, much remains uncertain about the signaling pathways in pathological states like heart failure, a state of impaired natriuretic peptide function. Elevated levels of ANP and BNP in heart failure correlate with disease severity and have a prognostic value. Synthetic ANP and BNP have been studied for their therapeutic role in hypertension and heart failure, and promising trials are under way. In recent years, the expression of ANP and BNP in human adipocytes has come to light. Through their role in promotion of adipocyte browning, lipolysis, lipid oxidation, and modulation of adipokine secretion, they have emerged as key regulators of energy consumption and metabolism. NPR-A signaling in skeletal muscles and adipocytes is emerging as pivotal to the maintenance of long-term insulin sensitivity, which is disrupted in obesity and reduced glucose-tolerance states. Genetic variants in the genes encoding for ANP and BNP have been associated with a favorable cardiometabolic profile. In this review, we discuss several pathways that have been proposed to explain the role of NPs as endocrine networkers. There is much to be explored about the therapeutic role of NPs in improving metabolic milieu.

Annexin A1 is a Potential Novel Biomarker of Congestion in Acute Heart Failure.

OBJECTIVES: This study sought to identify the role of annexin A1 (AnxA1) as a congestion marker in acute heart failure (AHF) and to identify its putative role in predicting clinical outcomes. BACKGROUND: AnxA1 is a protein that inhibits inflammation following ischemia-reperfusion injury in cardiorenal tissues. Because AHF is a state of tissue hypoperfusion, we hypothesized that plasma AnxA1 levels are altered in AHF. METHODS: In the Renal Optimization Strategies Evaluation (ROSE) trial, patients hospitalized for AHF with kidney injury were randomized to receive dopamine, nesiritide, or placebo for 72 hours in addition to diuresis. In a subanalysis, plasma AnxA1 levels were measured at baseline and at 72 hours in 275 patients. Participants were divided into 3 tertiles based on their baseline AnxA1 levels. RESULTS: The prevalence of peripheral edema 2+ increased with increasing AnxA1 levels (P < .007). Cystatin C, blood urea nitrogen, and kidney injury molecule-1 plasma levels were higher among participants in tertile 3 vs tertiles 1 or 2 (P< .05). Patients with a congestion score of 4 had a mean baseline AnxA1 level 8.63 units higher than those with a congestion score of 0 (P = .03). Patients in tertiles 2 and 3 were twice as likely to experience creatinine elevation as patients in tertile 1 (P = .03). Patients in tertiles 2 and 3 were at a higher risk of 60-day all-cause mortality or heart failure hospitalization and 180-day all-cause mortality (P < .05). CONCLUSIONS: Among patients hospitalized for AHF with impaired kidney function, elevated AnxA1 levels are associated with worse congestion, higher risk for further creatinine elevation, and higher rates of 60-day morbidity or all-cause mortality and 180-day all-cause mortality. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01132846.