Integrating High-Sensitivity Troponin T and Sacubitril/Valsartan Treatment in HFpEF: The PARAGON-HF Trial

Advance in the pharmacological and comorbidities management of heart failure with preserved ejection fraction: evidence from clinical trials

The prevalence of heart failure with preserved ejection fraction (HFpEF) accounts for approximately 50% of the total heart failure population, and with the aging of the population and the increasing prevalence of hypertension, obesity, and type 2 diabetes (T2DM), the incidence of HFpEF continues to rise and has become the most common subtype of heart failure. Compared with heart failure with reduced ejection fraction, HFpEF has a more complex pathophysiology and is more often associated with hypertension, T2DM, obesity, atrial fibrillation, renal insufficiency, pulmonary hypertension, obstructive sleep apnea, and other comorbidities. HFpEF has generally been considered a syndrome with high phenotypic heterogeneity, and no effective treatments have been shown to reduce mortality to date. Diuretics and comorbidity management are traditional treatments for HFpEF; however, they are mostly empirical due to a lack of clinical evidence in the setting of HFpEF. With the EMPEROR-Preserved and DELIVER results, sodium-glucose cotransporter 2 inhibitors become the first evidence-based therapies to reduce rehospitalization for heart failure. Subgroup analyses of the PARAGON-HF, TOPCAT, and CHARM-Preserved trials suggest that angiotensin receptor-neprilysin inhibitors, spironolactone, and angiotensin II receptor blockers may be beneficial in patients at the lower end of the ejection fraction spectrum. Other potential pharmacotherapies represented by non-steroidal mineralocorticoid receptor antagonists finerenone and antifibrotic agent pirfenidone also hold promise for the treatment of HFpEF. This article intends to review the clinical evidence on current pharmacotherapies of HFpEF, as well as the comorbidities management of atrial fibrillation, hypertension, T2DM, obesity, pulmonary hypertension, renal insufficiency, obstructive sleep apnea, and iron deficiency, to optimize the clinical management of HFpEF.

Heart Failure with Preserved Ejection Fraction: How to Deal with This Chameleon

Heart failure with preserved ejection fraction (HFpEF) is characterized by a notable heterogeneity in both phenotypic and pathophysiological features, with a growing incidence due to the increase in median age and comorbidities such as obesity, arterial hypertension, and cardiometabolic disease. In recent decades, the development of new pharmacological and non-pharmacological options has significantly impacted outcomes, improving clinical status and reducing mortality. Moreover, a more personalized and accurate therapeutic management has been demonstrated to enhance the quality of life, diminish hospitalizations, and improve overall survival. Therefore, assessing the peculiarities of patients with HFpEF is crucial in order to obtain a better understanding of this disorder. Importantly, comorbidities have been shown to influence symptoms and prognosis, and, consequently, they should be carefully addressed. In this sense, it is mandatory to join forces with a multidisciplinary team in order to achieve high-quality care. However, HFpEF remains largely under-recognized and under-treated in clinical practice, and the diagnostic and therapeutic management of these patients remains challenging. The aim of this paper is to articulate a pragmatic approach for patients with HFpEF focusing on the etiology, diagnosis, and treatment of HFpEF.

Comprehensive diagnostic workup in patients with suspected heart failure and preserved ejection fraction

Diagnosis of heart failure with preserved ejection fraction (HFpEF) can be challenging and it could require different tests, some of which are affected by limited availability. Nowadays, considering that new therapies are available for HFpEF and related conditions, a prompt and correct diagnosis is relevant. However, the diagnostic role of biomarker level, imaging tools, score-based algorithms and invasive evaluation, should be based on the strengths and weaknesses of each test. The aim of this review is to help the clinician in diagnosing HFpEF, overcoming the diagnostic uncertainty and disentangling among the different underlying causes, in order to properly treat this kind of patient.

Sacubitril/valsartan attenuates myocardial inflammation, hypertrophy, and fibrosis in rats with heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) represents a multifaceted syndrome related to complex pathologic mechanisms. Sacubitril/valsartan (Sac/val) has demonstrated therapeutic efficacy in HFpEF treatment. However, additional research is required to elucidate its pharmacological mechanisms. Accordingly, this study aimed to explore the potential therapeutic effects of Sac/val in HFpEF rats and the underlying molecular mechanisms. In this study, rats with HFpEF were induced by subjecting spontaneously hypertensive rats to a diet rich in fats, salts, and sugars, along with administering streptozotocin. Subsequently, they were administered Sac/val at a daily dosage of 18 mg/kg. Finally, cardiac structure and function were assessed using echocardiography; Hematoxylin and eosin staining and Masson's trichrome staining were employed to evaluate the pathological changes; Quantitative real-time polymerase chain reaction and Western blot analysis were conducted to determine the expression of pertinent mRNA and proteins. Sac/val treatment attenuated left ventricular (LV) remodeling and diastolic dysfunction in HFpEF rats, possibly related to its anti-inflammatory, anti-hypertrophic, and anti-fibrotic efficacy. Mechanistically, Sac/val might inhibit inflammation by down-regulating cell adhesion molecule (intercellular adhesion molecule-1 (ICAM-1) and vascular endothelial cell adhesion molecule-1 (VCAM-1)) expression. Additionally, it blocked the phosphorylation of glycogen synthase kinase 3β (GSK-3β) to prevent cardiomyocyte hypertrophy. Furthermore, it effectively suppressed myocardial fibrosis by inhibiting the transforming growth factor-beta1 (TGF-β1)/Smads pathway. Our findings suggest that Sac/val improved LV remodeling and diastolic dysfunction, potentially attributed to its anti-inflammatory, anti-hypertrophic, and anti-fibrotic effects. These results provide a sound theoretical rationale for the clinical application of Sac/val in patients with HFpEF.

SGLT2-Inhibitors on HFpEF Patients. Role of Ejection Fraction

Results from DELIVER trial and publication of EMPEROR-Preserved with sodium-glucose cotransporter 2 (SGLT2) inhibitors in patients with heart failure (HF) with ejection fraction (EF) > 40% represent a significant step forward in the treatment of HF with preserved EF (HFpEF). However, detailed analysis and attenuation of effect at higher EF levels have sparked some doubts about whether empagliflozin is effective across the entire spectrum of EF. HFpEF is no longer considered as one disease entity, but has been reconceptualized as a heterogenous group of phenotypes with derangements in multiple organ systems, driven by comorbidities. This heterogeneity suggests that it should not be considered as a single group in terms of treatment goals or clinical approach. Future research at the higher range of EF should ideally tailor investigations for unequivocally preserved EF (> 50%), consider the dynamic nature of EF over time, and use low-variability imaging techniques such as CMR. Furthermore, classifications based on pathophysiology and HF phenotypes beyond the EF construct will shape the design of future trials and help narrow down groups of patients who may respond to personalized treatment.

What Is the Clinical Utility of Cardiac Troponins in Heart Failure? Are They Modifiable Beyond Their Prognostic Value?

PURPOSE OF REVIEW

To review the role of cardiac troponin (cTn) for prognosis in acute and chronic heart failure, and for predicting heart failure; and to explore the association between troponin and response to heart failure therapies, with an eye toward a possible role for troponin in a personalized approach to heart failure management, beyond prognosis.

RECENT FINDINGS

A number of therapies, including the neprilysin inhibitor sacubitril/valsartan and sodium-glucose cotransporter-2 inhibitors, have recently been shown to improve outcomes in heart failure patients. Most studies suggest that these agents improve outcomes regardless of baseline cTn concentration, but have greater absolute benefit among patients with highest cTn and baseline risk. Troponin is prognostic across the heart failure spectrum, but whether it can significantly help with heart failure prevention and with tailoring and guiding heart failure treatments and interventions remains unknown.

Laboratory and Metabolomic Fingerprint in Heart Failure with Preserved Ejection Fraction: From Clinical Classification to Biomarker Signature

Heart failure with preserved ejection fraction (HFpEF) remains a poorly characterized syndrome with many unknown aspects related to different patient profiles, various associated risk factors and a wide range of aetiologies. It comprises several pathophysiological pathways, such as endothelial dysfunction, myocardial fibrosis, extracellular matrix deposition and intense inflammatory system activation. Until now, HFpEF has only been described with regard to clinical features and its most commonly associated risk factors, disregarding all biological mechanisms responsible for cardiovascular deteriorations. Recently, innovations in laboratory and metabolomic findings have shown that HFpEF appears to be strictly related to specific cells and molecular mechanisms' dysregulation. Indeed, some biomarkers are efficient in early identification of these processes, adding new insights into diagnosis and risk stratification. Moreover, recent advances in intermediate metabolites provide relevant information on intrinsic cellular and energetic substrate alterations. Therefore, a systematic combination of clinical imaging and laboratory findings may lead to a 'precision medicine' approach providing prognostic and therapeutic advantages. The current review reports traditional and emerging biomarkers in HFpEF and it purposes a new diagnostic approach based on integrative information achieved from risk factor burden, hemodynamic dysfunction and biomarkers' signature partnership.

Assessment of Biomarkers of Myocardial injury, Inflammation, and Renal Function in Heart Failure With Reduced Ejection Fraction: The VICTORIA Biomarker Substudy

BACKGROUND

Circulating biomarkers may be useful in understanding prognosis and treatment efficacy in heart failure with reduced ejection fraction. In the VICTORIA (Vericiguat Global Study in Subjects with Heart Failure with Reduced Ejection Fraction) trial, vericiguat, a soluble guanylate cyclase stimulator, decreased the primary outcome of cardiovascular death or heart failure hospitalization in heart failure with reduced ejection fraction. We evaluated biomarkers of cardiac injury, inflammation, and renal function for associations with outcomes and vericiguat treatment effect.

METHODS AND RESULTS

High-sensitivity cardiac troponin T (hs-cTnT), growth differentiation factor-15 (GDF-15), interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP), and cystatin C were measured at baseline and 16 weeks. Associations of biomarkers with the primary outcome and its components were estimated. Interaction with study treatment was tested. Changes in biomarkers over time were examined by study treatment. One or more biomarkers were measured in 4652 (92%) of 5050 participants at baseline and 4063 (81%) at 16 weeks. After adjustment, higher values of hs-cTnT, growth differentiation factor-15, and interleukin-6 were associated with the primary outcome, independent of N-terminal pro-B-type natriuretic peptide. Higher hs-cTnT values were associated with a hazard ratio per log standard deviation of 1.21 (95% confidence interval 1.14-1.27). A treatment interaction with vericiguat was evident with hs-cTnT and cardiovascular death (P = .04), but not HF hospitalization (P = .38). All biomarkers except cystatin C decreased over 16 weeks and no relationship between treatment assignment and changes in biomarker levels was observed.

CONCLUSIONS

hs-cTnT, growth differentiation factor-15, and interleukin-6 levels were associated with risk of the primary outcome in VICTORIA (Vericiguat Global Study in Subjects with Heart Failure with Reduced Ejection Fraction). Uniquely, lower hs-cTnT was associated with a lower rate of cardiovascular death but not HF hospitalization after treatment with vericiguat.

Effects of sacubitril/valsartan in ESRD patients undergoing hemodialysis with HFpEF

Introduction

Heart failure with preserved ejection fraction (HFpEF), which is a common co-morbidity in patients with maintenance hemodialysis (MHD), results in substantial mortality and morbidity. However, there are still no effective therapeutic drugs available for HFpEF currently. Sacubitril/valsartan has been shown to significantly improve clinical outcomes and reverse myocardial remodeling among patients with heart failure with reduced ejection fraction (HFrEF). The effect of sacubitril/valsartan in MHD patients with HFpEF remains unclear. Our study was designed to assess the efficacy and safety of sacubitril/valsartan in MHD patients with HFpEF.

Methods

A total of 247 MHD patients with HFpEF treated with sacubitril/valsartan were included in this retrospective study. Patients were followed up regularly after medication treatment. The alterations in clinical, biochemical, and echocardiographic parameters before and after taking sacubitril/valsartan were collected. In addition, the safety of the sacubitril/valsartan treatment was also assessed. Among those 247 patients with MHD, 211 patients were already in treatment with angiotensin converting enzyme inhibitors (ACEi)/angiotensin receptor blockers (ARBs) before being treated with sacubitril/valsartan. We also performed an analysis to compare the differences between the 211 patients who had previously received ACEi/ARB treatment and the 36 patients who were sacubitril/valsartan naive.

Results

Among those 247 patients with MHD, compared with baseline levels, systolic blood pressure (BP) (149.7 ± 23.6 vs. 137.2 ± 21.0 mmHg, P < 0.001), diastolic BP (90.2 ± 16.1 vs. 84.5 ± 14.1 mmHg, P < 0.001), heart rate (83.5 ± 12.5 vs. 80.0 ± 8.7 bpm, P < 0.001), N-terminal B-type natriuretic peptide precursor (NT-proBNP) [29125.0 (11474.5, 68532.0) vs. 12561.3 (4035.0, 37575.0) pg/ml, P < 0.001], and cardiac troponin I [0.044 (0.025, 0.078) vs. 0.0370 (0.020, 0.064) μg/L, P = 0.009] were markedly decreased after treatment with sacubitril/valsartan. New York Heart Association (NYHA) functional class showed a notable trend of improvement after 3–12 months of follow-up. Echocardiographic parameters including left ventricular posterior wall thickness (LVPWT) (11.8 ± 2.0 vs. 10.8 ± 1.9 mm, P < 0.001), intraventricular septal thickness in diastole (11.8 ± 2.0 vs. 11.2 ± 2.0 mm, P < 0.001), left ventricular end-diastolic diameter (53.8 ± 6.9 vs. 51.2 ± 7.1 mm, P < 0.001), left atrial diameter (LAD) (40.5 ± 6.2 vs. 37.2 ± 7.2 mm, P < 0.001), left ventricular end-diastolic volume (LVEDV) [143.0 (111.5, 174.0) vs. 130.0 (105.0, 163.0) ml, P < 0.001], left ventricular end-systolic volume (LVESV) [57.0 (43.0, 82.5) vs. 48.0 (38.0, 74.0) ml, P < 0.001], and pulmonary arterial systolic pressure [39.0 (30.5, 50.0) vs. 28.0 (21.0, 37.5) mmHg, P < 0.001] were significantly reduced after initiating the treatment of sacubitril/valsartan. The parameters of left ventricular diastolic function including E/A ratio [0.8 (0.7, 1.3) vs. 0.9 (0.8, 1.3), P = 0.008], maximal tricuspid regurgitation velocity [2.7 (2.5, 3.2) vs. 2.4 (2.0, 2.8) m/s, P < 0.001], septal e’wave velocity (8.0 ± 0.6 vs. 8.2 ± 0.5 cm/s, P = 0.001), lateral e’ wave velocity (9.9 ± 0.8 vs. 10.2 ± 0.7 cm/s, P < 0.001), E/e’ [8.3 (6.4, 11.8) vs. 7.2 (6.1, 8.9), P < 0.001], and left atrial volume index (37.9 ± 4.2 vs. 36.4 ± 4.1 ml/m², P < 0.001) were significantly improved by sacubitril/valsartan. Among 211 patients who were already in treatment with ACEi/ARB and 36 patients who were sacubitril/valsartan naive, the improvement of cardiac function demonstrated by clinical outcomes and echocardiographic parameters were similar to the previous one of the 247 MHD patients with HFpEF. During the follow-up, none of the patients showed severe adverse drug reactions.

Conclusion

Our study suggested that sacubitril/valsartan treatment in MHD patients with HFpEF was effective and safe.

Biomarkers in HFpEF for Diagnosis, Prognosis, and Biological Phenotyping

PURPOSE OF REVIEW

The heterogeneity of heart failure with preserved ejection fraction (HFpEF) is responsible for the limited success of broad management strategies. The role of biomarkers has been evolving helping to provide insight into the diversity of pathophysiology, prognosis, and potential targets for treatments. We will review the role of traditional and novel biomarkers in diagnosing, prognosticating, and evolving the management of patients with HFpEF. As circulating biomarker discovery rapidly evolves, we will explore technology for new biomarker discovery with examples of successful implementation.

RECENT FINDINGS

Besides cardiac-specific biomarkers (natriuretic peptides and troponin), other novel nonspecific biomarkers increasingly identify the diversity of pathophysiological mechanisms of HFpEF including inflammation, fibrosis, and renal dysfunction. Newer approaches have provided increasing granularity providing opportunities to integrate large amounts of information from proteomics and genomics as biomarkers of interest in HFpEF. HFpEF has been marked with failure of many medications to show benefit, whether measuring single targeted biomarkers or broader targeted discovery proteomics or genomic circulating biomarkers are providing increasing opportunities to better understand and manage HFpEF patients.

Biomarker-driven prognostic models in chronic heart failure with preserved ejection fraction: the EMPEROR-Preserved trial

AIMS

Biomarker-driven prognostic models incorporating N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin T (hs-cTnT) in heart failure (HF) with preserved ejection fraction (HFpEF) are lacking. We aimed to generate a biomarker-driven prognostic tool for patients with chronic HFpEF enrolled in EMPEROR-Preserved.

METHODS AND RESULTS

Multivariable Cox regression models were created for (i) the primary composite outcome of HF hospitalization or cardiovascular death, (ii) all-cause death, (iii) cardiovascular death, and (iv) HF hospitalization. PARAGON-HF was used as a validation cohort. NT-proBNP and hs-cTnT were the dominant predictors of the primary outcome, and in addition, a shorter time since last hospitalization, New York Heart Association (NYHA) class III or IV, history of chronic obstructive pulmonary disease (COPD), insulin-treated diabetes, low haemoglobin, and a longer time since HF diagnosis were key predictors (eight variables, all p < 0.001). The consequent primary outcome risk score discriminated well (c-statistic = 0.75) with patients in the top 10th of risk having an event rate >22× higher than those in the bottom 10th. A model for HF hospitalization alone had even better discrimination (c = 0.79). Empagliflozin reduced the risk of cardiovascular death or hospitalization for HF in patients across all risk levels. NT-proBNP and hs-cTnT were also the dominant predictors of all-cause and cardiovascular mortality followed by history of COPD, low albumin, older age, left ventricular ejection fraction ≥50%, NYHA class III or IV and insulin-treated diabetes (eight variables, all p < 0.001). The mortality risk model had similar discrimination for all-cause and cardiovascular mortality (c-statistic = 0.72 for both). External validation provided c-statistics of 0.71, 0.71, 0.72, and 0.72 for the primary outcome, HF hospitalization alone, all-cause death, and cardiovascular death, respectively.

CONCLUSIONS

The combination of NT-proBNP and hs-cTnT along with a few readily available clinical variables provides effective risk discrimination both for morbidity and mortality in patients with HFpEF. A predictive tool-kit facilitates the ready implementation of these risk models in routine clinical practice.

Biomarkers of HFpEF: Natriuretic Peptides, High-Sensitivity Troponins and Beyond

Heart failure (HF) is a significant cause of morbidity and mortality worldwide. HF with preserved ejection fraction (HFpEF) is a complex syndrome, often participated by several cardiac and extracardiac conditions, including chronic kidney disease, pulmonary disease, anaemia and advanced age. Circulating biomarkers reflecting pathophysiological pathways involved in HFpEF development and progression may assist clinicians in early diagnosis and management of this condition. Natriuretic peptides (NPs) are cardioprotective hormones released by cardiomyocytes in response to pressure or volume overload and in response to activation of neuro-endocrine-immune system. The relevance of B-type NP (BNP) and N-terminal pro-B-type NP (NT-proBNP) for diagnosis and risk stratification has been extensively demonstrated, and these biomarkers are emerging tools for population screening and as guides to the start of treatment in subclinical HF. On the contrary, conflicting evidence exists on the value of NPs to guide HF therapy. Among the other biomarkers, high-sensitivity troponins and soluble suppression of tumorigenesis-2 are the most promising biomarkers for risk stratification, predicting outcome independently from NPs. In this review, some novel biomarkers are being tested in such clinical scenario, more tightly linked to specific pathophysiological processes of cardiac damage.

Sodium–Glucose Cotransporter 2 Inhibitors in Heart Failure with Preserved Ejection Fraction: Rationale for and Practical Use of a Successful Therapy

Heart failure (HF) with preserved left ventricular ejection fraction is a common disease with a poor prognosis and rising prevalence in the community. The current paradigm of treatment includes symptomatic therapy, such as diuretics, and risk factor control and treatment of comorbidities. According to European guidelines, there is no effective therapy for patients with HF with left ventricular ejection fraction (LVEF) ≥50%, while drugs normally used in HF with reduced LVEF might also be effective for patients with mildly reduced LVEF (40–50%), with a IIB class of recommendation. The recently published EMPEROR-Preserved trial has challenged current guidelines, demonstrating improved outcomes in patients with HF and LVEF >40% with the sodium–glucose cotransporter 2 inhibitor (SGLT2I) empagliflozin, compared with placebo. This result was consistent in patients with and without diabetes as well as in those with LVEF below and above 50%. The authors describe the rationale for this therapy, presenting the main results of the EMPEROR-Preserved trial, and provide some recommendations for the everyday clinical management of HF with preserved left ventricular ejection with an SGLT2I.

Biomarkers in Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous disorder developing from multiple aetiologies with overlapping pathophysiological mechanisms. HFpEF diagnosis may be challenging, as neither cardiac imaging nor physical examination are sensitive in this situation. Here, we review biomarkers of HFpEF, of which the best supported are related to myocardial stretch and injury, including natriuretic peptides and cardiac troponins. An overview of biomarkers of inflammation, extracellular matrix derangements and fibrosis, senescence, vascular dysfunction, anaemia/iron deficiency and obesity is also provided. Finally, novel biomarkers from -omics technologies, including plasma metabolites and circulating microRNAs, are outlined briefly. A cardiac-centred approach to HFpEF diagnosis using natriuretic peptides seems reasonable at present in clinical practice. A holistic approach including biomarkers that provide information on the non-cardiac components of the HFpEF syndrome may enrich our understanding of the disease and may be useful in classifying HFpEF phenotypes or endotypes that may guide patient selection in HFpEF trials.

A multidisciplinary approach to heart failure care in the hospital: improving the patient journey

Despite advancements in care for patients with heart failure (HF), morbidity and mortality remain high. Hospitalizations and readmissions for HF have been the focus of significant attention among health care providers and payers, with an eye towards reducing health care costs. However, considerable variability exists with regard to inpatient workflows and management for patients with HF, which represents a significant opportunity to improve care. Here we provide a summary of optimal inpatient management strategies for HF, focusing on the multidisciplinary team of emergency medicine providers, admitting hospitalists, cardiovascular consultants, pharmacists, nurses, and social workers. The patient journey serves as the template for this review article, from the initial presentation in the emergency department, to decongestion and stabilization, optimization of guideline-directed medical therapy, and discharge and appropriate disposition. Lastly, this review aims not to be proscriptive but rather to provide best practices that are clinically relevant and actionable, with the goal of improving care for patients during the sentinel hospitalization for HF.

Heart failure with preserved ejection fraction: recent concepts in diagnosis, mechanisms and management

It is estimated that half of all patients with heart failure (HF) have HF with preserved ejection fraction (HFpEF). Yet this form of HF remains a diagnostic and therapeutic challenge. Differentiating HFpEF from other causes of dyspnoea may require advanced diagnostic methods, such as exercise echocardiography, invasive haemodynamics and investigations for 'HFpEF mimickers'. While the classification of HF has relied heavily on cut-points in left ventricular ejection fraction (LVEF), recent evidence points towards a gradual shift in underlying mechanisms, phenotypes and response to therapies as LVEF increases. For example, among patients with HF, the proportion of hospitalisations and deaths due to cardiac causes decreases as LVEF increases. Medication classes that are efficacious in HF with reduced ejection fraction (HFrEF) have been less so at higher LVEF ranges, decreasing the risk of HF hospitalisation but not cardiovascular or all-cause death in HFpEF. These observations reflect the burden of non-cardiac comorbidities as LVEF increases and highlight the complex pathophysiological mechanisms, both cardiac and non-cardiac, underpinning HFpEF. Treatment with sodium-glucose cotransporter 2 inhibitors reduces the risk of composite cardiovascular events, driven by a reduction in HF hospitalisations; renin-angiotensin-aldosterone blockers and angiotensin-neprilysin inhibitors result in smaller reductions in HF hospitalisations among patients with HFpEF. Comprehensive management of HFpEF includes exercise as well as treatment of risk factors and comorbidities. Classification based on phenotypes may facilitate a more targeted approach to treatment than LVEF categorisation, which sets arbitrary cut-points when LVEF is a continuum. This narrative review summarises the pathophysiology, diagnosis, classification and management of patients with HFpEF.