Associations With and Prognostic and Discriminatory Role of N-Terminal Pro–B-Type Natriuretic Peptide in Heart Failure With Preserved Versus Mid-range Versus Reduced Ejection Fraction

Biomarkers in heart failure: a focus on natriuretic peptides

While progress has been made in the management of most aspects of cardiovascular disease, the incidence and prevalence of heart failure (HF) remains high. HF affects around a million people in the UK and has a worse prognosis than most cancers. Patients with HF are often elderly with complex comorbidities, making accurate assessment of HF challenging. A timely diagnosis and initiation of evidence-based treatments are key to prevent hospitalisation and improve outcomes in this population. Biomarkers have dramatically impacted the way patients with HF are evaluated and managed. The most studied biomarkers in HF are natriuretic peptides (NPs). Since their discovery in the 1980s, there has been an explosion of work in the field of NPs and they have become an important clinical tool used in everyday practice to guide diagnosis and prognostic assessment of patients with HF. In this article, we will review the physiology of NPs and study their biological effects. Then, we will discuss the role of NPs in the diagnosis, management and prognostication of patients with HF. We will also explore the role of NPs as a potential therapeutic agent.

Heart failure registries - Future directions

Heart failure (HF) is a growing, global public health issue. Despite advances in HF care, many challenges remain and HF outcomes are poor. Some of the major reasons for this are the lack of understanding and treatment for certain HF sub-types as well as the lack of implementation of treatment in areas where effective treatment exists. HF registries provide the opportunity to transform clinical research and patient care. Recently the registry-based randomized clinical trial has emerged as a pragmatic and inexpensive alternative to the gold standard in clinical trial design, the randomized controlled trial. Registries may also provide platforms for strategy trials, implementation trials, and screening. Using examples from the Swedish Heart Failure Registry and others, the present review provides insights into how registry-based research can address many of the unmet needs in HF.

Diagnostic and Prognostic Value of Aminoterminal Prohormone of Brain Natriuretic Peptide in Heart Failure with Mildly Reduced Ejection Fraction Stratified by the Degree of Renal Dysfunction

Limited data concerning the diagnostic and prognostic value of blood-derived biomarkers in heart failure with mildly reduced ejection fraction (HFmrEF) is available. This study investigates the diagnostic and prognostic value of aminoterminal prohormone of brain natriuretic peptide (NT-proBNP) in patients with HFmrEF, stratified by the estimated glomerular filtration rate (eGFR). Consecutive patients with HFmrEF were retrospectively included at one institution from 2016 to 2022. First, the diagnostic value of NT-proBNP for acute decompensated heart failure (ADHF) was tested. Thereafter, the prognostic value of NT-proBNP levels was tested for 30-months all-cause mortality in patients with ADHF. From a total of 755 patients hospitalized with HFmrEF, the rate of ADHF was 42%. Patients with ADHF revealed higher NT-proBNP levels compared to patients without (median 5394 pg/mL vs. 1655 pg/mL; p = 0.001). NT-proBNP was able to discriminate ADHF with an area under the curve (AUC) of 0.777 (p = 0.001), with the highest AUC in patients with eGFR ≥ 60 mL/min (AUC = 0.800; p = 0.001), and no diagnostic value was seen in eGFR < 30 mL/min (AUC = 0.576; p = 0.210). Patients with NT-proBNP levels > 3946 pg/mL were associated with higher rates of all-cause mortality at 30 months (57.7% vs. 34.4%; HR = 2.036; 95% CI 1.423-2.912; p = 0.001), even after multivariable adjustment (HR = 1.712; 95% CI 1.166-2.512; p = 0.006). In conclusion, increasing NT-proBNP levels predicted the risk of ADHF and all-cause mortality in patients with HFmrEF and preserved renal function; however, NT-proBNP levels were not predictive in patients with HFmrEF and eGFR < 30 mL/min.

From mid-range to mildly reduced ejection fraction heart failure: A call to treat

The historical classification of heart failure (HF) has considered two distinct subgroups, HF with reduced ejection fraction (HFrEF), generally classified as EF below 40%, and HF with preserved ejection fraction (HFpEF) variably classified as EF above 40%, 45% or 50%. One of the principal reasons behind this distinction was related to presence of effective therapy in HFrEF, but not in HFpEF. Recently the expanding knowledge in the specific subgroup of patient with a LVEF between 41% and 49% and the potential benefit of new therapies and of those used in patients with LVEF below 40%, has led to rename this group as HF with mildly reduced EF (HFmrEF). In this review we discuss the reasons behind this modification, we summarize the main characteristics of HFmrEF the similarities and differences with the two other EF categories, and finally we provide a comprehensive overview of the current available evidence supporting the treatment of patients with HFmrEF.

Heart failure with preserved ejection fraction: key stumbling blocks for experimental drugs in clinical trials

INTRODUCTION

Heart failure with preserved ejection fraction (HFpEF) is a disease process with a high prevalence. Accounting for more than 50% of all heart failure cases, it carries a significant mortality. So far, there has been a lack of therapeutic options that truly show improvement in morbidity and mortality. Certain novel therapies have shown a decrease in heart failure hospitalizations, however, this beneficial effect was more pronounced for heart failure patients with mildly reduced ejection fraction (EF).

AREAS COVERED

This review summarizes the pathophysiology of the disease to help elucidate the differences between heart failure with reduced ejection fraction (HFrEF), and HFpEF, which could explain why therapies are successful in one (rather than the other). At the focus of this review are non-standardized nomenclature across major trials, the challenges of finding a therapeutic agent for such a heterogeneous population, and identification of specific phenotypes that have different outcomes and could be a target for future therapies.

EXPERT OPINION

Lack of standardized diagnostic criteria, associated with population heterogeneity, might explain why trials have failed to improve outcomes for patients with HFpEF. Standardizing phenotypes and recapitulating these phenotypes in animal models, as well as understanding the mechanisms of the disease at the molecular level could be the first steps in identifying promising therapeutic options.

Biomarker changes as surrogate endpoints in early-phase trials in heart failure with reduced ejection fraction

AIMS

No biomarker has achieved widespread acceptance as a surrogate endpoint for early-phase heart failure (HF) trials. We assessed whether changes over time in a panel of plasma biomarkers were associated with subsequent morbidity/mortality in HF with reduced ejection fraction (HFrEF).

METHODS AND RESULTS

In 1040 patients with HFrEF from the BIOSTAT-CHF cohort, we investigated the associations between changes in the plasma concentrations of 30 biomarkers, before (baseline) and after (9 months) attempted optimization of guideline-recommended therapy, on top of the BIOSTAT risk score and the subsequent risk of HF hospitalization/all-cause mortality using Cox regression models. C-statistics were calculated to assess discriminatory power of biomarker changes/month-nine assessment. Changes in N-terminal pro-B-type natriuretic peptide (NT-proBNP) and WAP four-disulphide core domain protein HE4 (WAP-4C) were the only independent predictors of the outcome after adjusting for their baseline plasma concentration, 28 other biomarkers (both baseline and changes), and BIOSTAT risk score at baseline. When adjusting for month-nine rather than baseline biomarkers concentrations, only changes in NT-proBNP were independently associated with the outcome. The C-statistic of the model including the BIOSTAT risk score and NT-proBNP increased by 4% when changes were considered on top of baseline concentrations and by 1% when changes in NT-proBNP were considered on top of its month-nine concentrations and the BIOSTAT risk score.

CONCLUSIONS

Among 30 relevant biomarkers, a change over time was significantly and independently associated with HF hospitalization/all-cause death only for NT-proBNP. Changes over time were modestly more prognostic than baseline or end-values alone. Changes in biomarkers should be further explored as potential surrogate endpoints in early phase HF trials.

Vericiguat in Patients with Coronary Artery Disease and Heart Failure with Reduced Ejection Fraction

AIMS

Coronary artery disease (CAD) portends worse outcomes in heart failure (HF). We aimed to characterize patients with CAD and worsening HF with reduced ejection fraction (HFrEF) and evaluate post hoc whether vericiguat's treatment effect varied according to CAD.

METHODS AND RESULTS

Cox proportional hazards were generated for the primary endpoint of cardiovascular death or HF hospitalization (CVD/HFH). CAD was defined as previous myocardial infarction, percutaneous coronary intervention, or coronary artery bypass grafting. Of 5048 patients in VICTORIA with available data on CAD status, 2704 had CAD and were older, were more frequently male, diabetic, and had a lower glomerular filtration rate than those without CAD (all p <0.0001). Use of implantable cardioverter defibrillators and cardiac resynchronization therapy (CRT) was higher in patients with versus without CAD (33.5 vs. 21.1%; p <0.0001 and 16.3 vs. 12.8%; p = 0.0006). The primary endpoint of CVD/HFH was higher in those with versus without CAD (40.6 vs. 30.1/100 patient-years; adjusted hazard ratio [HR] 1.23; p <0.001) as was all-cause mortality (17.9% vs. 12.7%; adjusted HR 1.32; p <0.001). The primary outcome of CVD/HFH associated with vericiguat in patients with or without CAD was 38.8 vs. 27.6 per 100 patient-years and for placebo was 42.6 vs. 32.7 per 100 patient-years (interaction p = 0.78).

CONCLUSION

In this post hoc study, CAD was associated with more CVD and HFH in patients with HFrEF and worsening HF. Vericiguat was beneficial and safe regardless of concomitant CAD. This article is protected by copyright. All rights reserved.

Heart failure with mid-range or mildly reduced ejection fraction

Left ventricular ejection fraction (EF) remains the major parameter for diagnosis, phenotyping, prognosis and treatment decisions in heart failure. The 2016 ESC heart failure guidelines introduced a third EF category for an EF of 40-49%, defined as heart failure with mid-range EF (HFmrEF). This category has been largely unexplored compared with heart failure with reduced EF (HFrEF; defined as EF <40% in this Review) and heart failure with preserved EF (HFpEF; defined as EF ≥50%). The prevalence of HFmrEF within the overall population of patients with HF is 10-25%. HFmrEF seems to be an intermediate clinical entity between HFrEF and HFpEF in some respects, but more similar to HFrEF in others, in particular with regard to the high prevalence of ischaemic heart disease in these patients. HFmrEF is milder than HFrEF, and the risk of cardiovascular events is lower in patients with HFmrEF or HFpEF than in those with HFrEF. By contrast, the risk of non-cardiovascular adverse events is similar or greater in patients with HFmrEF or HFpEF than in those with HFrEF. Evidence from post hoc and subgroup analyses of randomized clinical trials and a trial of an SGLT1-SGLT2 inhibitor suggests that drugs that are effective in patients with HFrEF might also be effective in patients with HFmrEF. Although the EF is a continuous measure with considerable variability, in this comprehensive Review we suggest that HFmrEF is a useful categorization of patients with HF and shares the most important clinical features with HFrEF, which supports the renaming of HFmrEF to HF with mildly reduced EF.

Sympathetic activation in heart failure with reduced and mildly reduced ejection fraction: the role of aetiology

Aim

While sympathetic overactivity in heart failure (HF) with reduced ejection fraction (HFrEF; EF < 40%) is well‐documented, it is ill‐defined in patients with mildly reduced EF (HFmrEF; EF 40–49%). Furthermore, the significance of ischaemic versus non‐ischaemic aetiology in sympathetic activation is also unclear and has yet to be studied in HF. Our goal was to compare muscle sympathetic nerve activity (MSNA) in HFmrEF and HFrEF patients and in healthy subjects, as well as to elucidate the influence of the underlying disease.

Methods and results

Twenty‐three HFrEF (age 58 ± 10 years), 33 HFmrEF patients (age 61 ± 10 years), including 11 subjects with non‐ischaemic cardiomyopathy in each HF groups and 10 healthy controls (age 55 ± 10 years), were studied. MSNA—detected by peroneal microneurography, continuous arterial pressure, and ECG—was recorded. MSNA frequency (burst/min) and incidence (burst/100 cycles) were calculated. Association with the patients' characteristics were assessed, and aetiology‐based comparisons were performed. Burst frequency demonstrated a significant stepwise increase in both HFmrEF (41 ± 11 burst/min) and HFrEF (58 ± 17 burst/min, P < 0.001) patients as compared with controls (27 ± 9; P < 0.001 for both HF groups). Similarly, burst incidences were 66 ± 17, 82 ± 15, and 36 ± 10 burst/100 cycles in HFmrEF, HFrEF patients, and in healthy controls, respectively (P < 0.001 for all). Burst frequencies in HF patients showed significant correlation with NT‐proBNP levels, and significant inverse correlations with the subjects' mean RR intervals, stroke volumes, pulse pressures, and EF.

Conclusions

Muscle sympathetic nerve activity parameters indicated significant sympathetic activation in both HFmrEF and HFrEF patients as compared with healthy controls with no difference in relation to ischaemic versus non‐ischaemic aetiology.

Heart Failure With Midrange Ejection Fraction: Prior Left Ventricular Ejection Fraction and Prognosis

Aims: Evidence-based guidelines for heart failure management depend mainly on current left ventricular ejection fraction (LVEF). However, fewer studies have examined the impact of prior LVEF. Patients may enter the heart failure with midrange ejection fraction (HFmrEF) category when heart failure with preserved ejection fraction (HFpEF) deteriorates or heart failure with reduced ejection fraction (HFrEF) improves. In this study, we examined the association between change in LVEF and adverse outcomes.

Methods: HFmrEF patients with at least two or more echocardiograms 3 months apart at the First Affiliated Hospital of Dalian Medical University between September 1, 2015 and November 30, 2019 were identified. According to the prior LVEF, the subjects were divided into improved group (prior LVEF < 40%), stable group (prior LVEF between 40 and 50%), and deteriorated group (prior LVEF ≥ 50%). The primary outcomes were cardiovascular death, all-cause mortality, hospitalization for worsening heart failure, and composite event of all-cause mortality or all-cause hospitalization.

Results: A total of 1,168 HFmrEF patients (67.04% male, mean age 63.60 ± 12.18 years) were included. The percentages of improved, stable, and deteriorated group were 310 (26.54%), 334 (28.60%), and 524 (44.86%), respectively. After a period of follow-up, 208 patients (17.81%) died and 500 patients met the composite endpoint. The rates of all-cause mortality were 35 (11.29%), 55 (16.47%), and 118 (22.52%), and the composite outcome was 102 (32.90%), 145 (43.41%), and 253 (48.28%) for the improved, stable, and deteriorated groups, respectively. Cox regression analysis showed that the deterioration group had higher risk of cardiovascular death (HR: 1.707, 95% CI: 1.064–2.739, P = 0.027), all-cause death (HR 1.948, 95% CI 1.335–2.840, P = 0.001), and composite outcome (HR 1.379, 95% CI 1.096–1.736, P = 0.006) compared to the improvement group. The association still remained significant after fully adjusted for both all-cause mortality (HR = 1.899, 95% CI 1.247–2.893, P = 0.003) and composite outcome (HR: 1.324, 95% CI: 1.020–1.718, P = 0.035).

Conclusion: HFmrEF patients are heterogeneous with three different subsets identified, each with different outcomes. Strategies for managing HFmrEF should include previously measured LVEF to allow stratification based on direction changes in LVEF to better optimize treatment.

NT-proBNP Qualifies as a Surrogate for Clinical End Points in Heart Failure

N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a well-established biomarker in heart failure (HF) but controversially discussed as a potential surrogate marker in HF trials. We analyzed the NT-proBNP/mortality relationship in real-world data (RWD) of 108,330 HF patients from the IBM Watson Health Explorys database and compared it with the NT-proBNP / clinical event end-point relationship in 20 clinical HF studies. With a hierarchical statistical model, we quantified the functional relationship and interstudy variability. To independently qualify the model, we predicted outcome hazard ratios in five phase III HF studies solely based on NT-proBNP measured early in the respective study. In RWD and clinical studies, the relationship between NT-proBNP and clinical outcome is well described by an Emax model. The NT-proBNP independent baseline risk (R0 , RWD/studies median (interstudy interquartile range): 5.5%/3.0% (1.7-4.9%)) is very low compared with the potential NT-proBNP-associated maximum risk (Rmax : 55.2%/79.4% (61.5-89.0%)). The NT-proBNP concentration associated with the half-maximal risk is comparable in RWD and across clinical studies (EC50 : 3,880/2,414 pg/mL (1,460-4,355 pg/mL)). Model-based predictions of phase III outcomes, relying on short-term NT-proBNP data only, match final trial results with comparable confidence intervals. Our analysis qualifies NT-proBNP as a surrogate for clinical outcome in HF trials. NT-proBNP levels after short treatment durations of less than 10 weeks quantitatively predict hazard ratios with confidence levels comparable to final trial readout. Early NT-proBNP measurement can therefore enable shorter and smaller but still reliable HF trials.

Are HFpEF and HFmrEF So Different? The Need to Understand Distinct Phenotypes

Traditionally, patients with heart failure (HF) are divided according to ejection fraction (EF) threshold more or <50%. In 2016, the ESC guidelines introduced a new subgroup of HF patients including those subjects with EF ranging between 40 and 49% called heart failure with midrange EF (HFmrEF). This group is poorly represented in clinical trials, and it includes both patients with previous HFrEF having a good response to therapy and subjects with initial preserved EF appearance in which systolic function has been impaired. The categorization according to EF has recently been questioned because this variable is not really a representative of the myocardial contractile function and it could vary in relation to different hemodynamic conditions. Therefore, EF could significantly change over a short-term period and its measurement depends on the scan time course. Finally, although EF is widely recognized and measured worldwide, it has significant interobserver variability even in the most accredited echo laboratories. These assumptions imply that the same patient evaluated in different periods or by different physicians could be classified as HFmrEF or HFpEF. Thus, the two HF subtypes probably subtend different responses to the underlying pathophysiological mechanisms. Similarly, the adaptation to hemodynamic stimuli and to metabolic alterations could be different for different HF stages and periods. In this review, we analyze similarities and dissimilarities and we hypothesize that clinical and morphological characteristics of the two syndromes are not so discordant.

Left atrial diameter and atrial fibrillation, but not elevated NT-proBNP, predict the development of pulmonary hypertension in patients with HFpEF

BACKGROUND

The determinants of pulmonary hypertension (PH) due to heart failure with preserved ejection fraction (HFpEF) have been poorly investigated in patients with cardiovascular diseases (CVD).

METHODS

From July 1 2017 to March 31 2019, a total of 149 consecutive HFpEF patients hospitalized with CVD were enrolled in this prospective cross-sectional study. A systolic pulmonary artery pressure (PASP) > 35 mmHg estimated by echocardiography was defined as PH-HFpEF. Logistic regression was performed to establish predictors of PH in HFpEF patients.

RESULTS

Overall, the mean age of participants was 72 ± 11 years, and 74 (49.7%) patients were females. A total of 59 (39.6%) patients were diagnosed with PH-HFpEF by echocardiography. The left atrial diameter (LAD) was related to the ratio of the transmitral flow velocities/mitral annulus tissue velocities in early diastole (E/E') and the left ventricular diameter in systole (LVDs). N-Terminal pro B-type natriuretic peptide (NT-proBNP) was not found to be associated with LAD and impaired diastolic or systolic function of the left ventricle. Multivariable logistic regression showed that atrial fibrillation (AF) increased the risk of PH-HFpEF incidence 3.46-fold with a 95% confidence interval (CI) of 1.44-8.32, P = 0.005. Meanwhile, LAD ≥ 45 mm resulted in a 3.43-fold increased risk, 95% CI: 1.51-7.75, P = 0.003. However, the significance levels of NT-proBNP, age and LVEF were underpowered in the regression model. Two variables, AF and LAD ≥ 45 mm, predicted the PH-HFpEF incidence (C-statistic = 0.773, 95% CI: 0.695-0.852, P < 0.001).

CONCLUSIONS

Two parameters associated with electrical and anatomical remodelling of the left atrium were related to the incidence of PH in HFpEF patients with CVD.

Heart failure with mid-range ejection fraction: pro and cons of the new classification of Heart Failure by European Society of Cardiology guidelines

Currently, the assessment of left ventricular ejection fraction (LVEF) is the cornerstone of the classification of patients with heart failure (HF). The mid-range LVEF (HFmrEF) category was identified in an attempt to uncover specific characteristics of these patients. So far, the analysis of trials, registries, and observational studies have demonstrated that patients with mid-range LVEF belong to a patient cohort with generally intermediate clinical profile as compared with other groups but with a remarkable variety of intrinsic phenotypes. This is due to the limitations of LVEF as the sole criterion to categorize patients with HF and characterize their prognosis, above all when it is >40%. To better define the HFmrEF phenotype, it is reasonable to consider other parameters, such as LVEF changes over time, HF aetiology, co-morbidities, and other imaging parameters. A multiparametric evaluation may contextualize a patient with HFmrEF in a more defined phenotype with a specific prognosis.

Limited value of NT-proBNP as a prognostic marker of all-cause mortality in patients with heart failure with preserved and mid-range ejection fraction in primary care: A report from the swedish heart failure register

Aim: The prognostic value of natriuretic peptides in the management of heart failure (HF) patients with ejection fraction (EF) <40% is well established, but is less known for those with EF ≥40% managed in primary care (PC). Therefore, the aim of this study is to describe the prognostic significance of plasma NT-proBNP in such patients managed in PC.Subjects: We included 924 HF patients (48% women) with EF ≥40% and NT-proBNP registered in the Swedish Heart Failure Registry. Follow-up was 1100 ± 687 days.Results: One-, three- and five-year mortality rates were 8.1%, 23.9% and 44.7% in patients with EF 40-50% (HFmrEF) and 7.3%, 23.6% and 37.2% in patients with EF ≥50% (HFpEF) (p = 0.26). Patients with the highest mean values of NT-proBNP had the highest all-cause mortality but wide standard deviations (SDs). In univariate regression analysis, there was an association only between NT-proBNP quartiles and all-cause mortality. In HFmrEF patients, hazard ratio (HR) was 1.96 (95% CI 1.60-2.39) p < 0.0001) and in HFpEF patients, HR was 1.72 (95% CI 1.49-1.98) p < 0.0001). In a multivariate Cox proportional hazard regression analysis, adjusted for age, NYHA class, atrial fibrillation and GFR class, this association remained regarding NT-proBNP quartiles [HR 1.83 (95% CI 1.38-2.44), p < 0.0001] and [HR 1.48 (95% CI 1.16-1.90), p = 0.0001], HFmrEF and HFpEF, respectively.Conclusion: NT-proBNP has a prognostic value in patients with HF and EF ≥40% managed in PC. However, its clinical utility is limited due to high SDs and the fact that it is not independent in this population which is characterized by high age and much comorbidity.Key pointsIt is uncertain whether NT-proBNP predicts risk in heart failure with preserved ejection fraction (EF > 40%, HFpEF) managed in primary care.We show that high NT-proBNP predicts increased all-cause mortality in HFpEF-patients managed in primary care.The clinical use is however limited due to large standard deviations, many co-morbidities and high age.Many of these co-morbidities contribute to all-cause mortality and management of these patients should also focus on these co-morbidities.

Sacubitril-valsartan versus enalapril for acute decompensated heart failure: a cost-effectiveness analysis

Background

The Comparison of Sacubitril–Valsartan versus Enalapril on Effect on NT-proBNP in Patients Stabilised from an Acute Heart Failure Episode (PIONEER-HF) trial demonstrated significant reductions in N-terminal pro-B-type natriuretic peptide. Our study explored the cost-effectiveness of the use of sacubitril-valsartan versus enalapril in acute decompensated heart failure from the Australian healthcare perspective.

Methods

A Markov model was designed using data from the PIONEER-HF trial to model the clinical progress and costs of patients over a lifetime time horizon. The model consisted of three health states: ‘alive and event-free’, ‘alive after non-fatal hospitalisation for acute decompensated heart failure’ or ‘dead’. Costs and utilities were estimated from published sources. The cost of sacubitril-valsartan (per the Australian pharmaceutical benefits schedule) was AU$7.08/day. Outcomes of interest were the incremental cost-effectiveness ratios in terms of cost per quality-adjusted life year gained and cost per year of life saved. Cost and benefits were discounted at 5.0% per annum.

Results

Compared to enalapril, sacubitril-valsartan was estimated to cost an additional AU$7464 (discounted) per person, but lead to 0.127 years of life saved (discounted) and 0.096 quality-adjusted life years gained (discounted) over a lifetime analysis. These equated to incremental cost-effectiveness ratios of AU$58,629/year of life saved (US$41,795, EU€58,629, GBP£32,001) and AU$77,889/quality-adjusted life year gained (US$55,526, EU€49,202, GBP£42,504). We have assumed a threshold of AU$50,000/quality-adjusted life year gained to suggest cost-effectiveness.

Conclusions

At its current acquisition price, sacubitril-valsartan in comparison to enalapril is not likely to be cost-effective in the management of acute decompensated heart failure in Australia. A price reduction of more than 25% would confer cost-effectiveness.

Heart Failure with Mid-Range Ejection Fraction - State of the Art

In 2016, the European Society of Cardiology (ESC) recognized heart failure (HF) with ejection fraction between 40 and 49% as a new HF phenotype, HF with mid-range ejection fraction (HFmrEF), with the main purpose of encouraging studies on this new category. In 2018, the Brazilian Society of Cardiology adhered to this classification and introduced HFmrEF in Brazil. This paper presents a narrative review of what the literature has described about HFmrEF. The prevalence of patients with HFmrEF ranged from 13 to 24% of patients with HF. Analyzing the clinical characteristics, HFmrEF shows intermediate characteristics or is either similar to HF with preserved ejection fraction (HFpEF) or to HF with reduced fraction (HFrEF). Regarding the prognosis, HFmrEF's all-cause mortality is similar to HFpEF's and lower than HFrEF's. Studies that analyzed cardiac mortality concluded that there was no significant difference between HFmrEF and HFrEF, both of which were lower than HFpEF. Despite the significant increase of publications on HFmrEF, there is a great scarcity of prospective studies and clinical trials that allow delineating specific therapies for this new phenotype. To better treat HFmrEF patients, it is fundamental that cardiologists and internists understand the differences and similarities of this new phenotype.

Prospective evaluation and long-term follow-up of patients referred to secondary care based upon natriuretic peptide levels in primary care

AIMS

The UK National Institute for Health and Care Excellence (UK-NICE) and European Society of Cardiology (ESC) guidelines advise natriuretic peptide (NP) assessment in patients presenting to primary care with symptoms possibly due to chronic heart failure (HF), to determine need for specialist involvement. This prospective service evaluation aimed to describe the diagnostic and prognostic utility of these guidelines.

METHODS AND RESULTS

We prospectively collected clinical, echocardiography and outcomes data (minimum 5 years) from all patients referred to the Leeds HF Service for 12 months of following the initiation of the NP-guideline-directed pathway. Between 1 May 2012 and 1 August 2013, 1020 people with symptoms possibly due to HF attended either with a raised NT-pro-BNP or a previous myocardial infarction (MI) with an overall rate of left ventricular systolic dysfunction (LVSD) of 33%. Of these, 991 satisfied the ESC criteria (NT-pro-BNP ≥125 pg/mL) in whom the rate of LVSD was 32%, and 821 the UK-NICE criteria in whom the rate of LVSD was 49% in those with a previous MI, 25% in those with NT-pro-BNP concentration 400-2000 pg/mL, and 54% in those with NT-pro-BNP concentration of >2000 pg/mL. An NT-pro-BNP concentration 125-400 pg/mL had a 12% risk of LVSD. Specificity was poor in women >70 years, who made up the largest proportion of attendees. Elevated NT-pro-BNP levels were associated with lower survival even in the absence of LVSD.

CONCLUSION

In people referred through the ESC and UK-NICE guidelines, elevated NT-pro-BNP is a marker of increased mortality risk, but there is wide variation in specificity for LVSD. Age- and sex-adjusted criteria might improve performance.

Prognostic impact of Framingham heart failure criteria in heart failure with preserved ejection fraction

AIMS

This study aims to assess prognostic impact of Framingham criteria for heart failure (FC-HF) in patients with stable heart failure (HF) with preserved ejection fraction (HFpEF).

METHODS AND RESULTS

In the prospective Karolinska-Rennes (KaRen) study, we assessed stable HFpEF patients after an acute HF episode. We evaluated associations between the four descriptive models of HFpEF and the composite endpoint of all-cause mortality and HF hospitalization. The descriptive models were FC-HF alone, FC-HF + natriuretic peptides (NPs) according to the PARAGON trial, FC-HF + NPs + echocardiographic HFpEF criteria according to European Society of Cardiology HF guidelines, and FC-HF + NPs + echocardiographic criteria according to the PARAGON trial. Out of the 539 patients enrolled in KaRen, 438 returned for the stable state revisit after 4-8 weeks, 13 (2.4%) patients died before the planned follow-up, and 88 patients (16%) declined or were unable to return. Three hundred ninety-nine patients have FC registered at follow-up, and among these, the four descriptive models were met in 107 (27%), 82 (22%), 61 (21%), and 69 (22%) patients, and not met in 292 (73%). The 107 patients that had FC-HF at stable state (descriptive model 1) could also be part of the other models because all patients in models 1-4 had to fulfil the FC-HF. The patients in model 0 did not fulfil the criteria for FC-HF but could have single FC. Of single FC, only pleural effusion predicted the endpoint [hazard ratio (HR) 3.38, 95% confidence interval (CI) 1.47-7.76, P = 0.004]. Patients without FC-HF had better prognosis than patients meeting FC-HF. The unadjusted associations between the four HFpEF descriptive models and the endpoint were HR 1.54, 95% CI 1.14-2.09, P = 0.005; HR 1.71, 95% CI 1.24-2.36, P = 0.002; HR 1.95, 95% CI 1.36-2.81, P = 0.001; and HR 2.05, 95% CI 1.45-2.91, P < 0.001, for descriptive models 1-4, respectively. No descriptive model independently predicted the endpoint.

CONCLUSIONS

In ambulatory HFpEF patients, a quarter met FC-HF, while most met NP and echocardiography criteria for HF. Residual FC-HF tended to be associated with increased risk for mortality and HF hospitalization, further strengthened by NPs and echocardiographic criteria, highlighting its role in clinical risk assessment.

N-terminal pro-B-type natriuretic peptide in chronic heart failure: The impact of sex across the ejection fraction spectrum

OBJECTIVE

The aim was to assess sex-specific differences in N-terminal B-type natriuretic peptide (NT-proBNP) regarding concentrations, predictors of high concentrations, and prognostic role, in a large and unselected population with chronic heart failure (HF) with preserved (HFpEF), mid-range (HFmrEF), and reduced ejection fraction (HFrEF).

METHODS AND RESULTS

In 9847 outpatients with HFpEF, HFmrEF, and HFrEF (49 vs. 35 vs. 25% females, respectively) from the Swedish HF Registry, median NT-proBNP concentrations were 1598 ng/L in females vs. 1310 ng/L in males in HFpEF, 1764 vs. 1464 ng/L in HFmrEF, and 2543 vs. 2226 ng/L in HFrEF (p < 0.05 for all). The differences persisted after multiple adjustment. The largest sex-difference in NT-proBNP levels was observed in HFpEF with sinus rhythm, where median concentrations were 1.4 folds higher in females (923 vs. 647 ng/L). Independent predictors of NT-proBNP levels (defined as above the different medians according to sex and HF phenotype) were overall consistent across sexes and EF. NT-proBNP levels were similarly associated with risk of all-cause death/HF hospitalization in both sexes regardless of EF.

CONCLUSION

Concentrations of NT-proBNP were higher in females across the EF spectrum, with larger relative differences in HFpEF with sinus rhythm. However, similar predictors of high levels were observed in both sexes. There were no sex-differences in the prognostic role of NT-proBNP. These findings support the use of NT-proBNP for prognostic purposes in chronic HF, regardless of sex.

The Swedish Heart Failure Registry: a living, ongoing quality assurance and research in heart failure

Heart failure (HF) represents a global pandemic. Although in HF with reduced ejection fraction (HFrEF) randomized controlled trials have provided effective treatments, prognosis still remains poor, with signals of undertreatment. HF with mid-range EF (HFmrEF) has no evidence-based therapy, and its characterization is ongoing. Trials in HF with preserved EF (HFpEF) have failed to provide any effective treatment, but there are several concerns about their design. Thus, current challenges in the HF field are: 1) optimizing the use of existing treatments in HFrEF; 2) developing and proving efficacy of new treatments, and of new use of existing treatments in HFpEF and HFmrEF. Here we describe how registry-based research can improve knowledge addressing the unmet needs in HF, and in particular we focus on the contribution of the Swedish Heart Failure Registry to this field.