Cardiac magnetic resonance in heart failure with preserved ejection fraction: myocyte, interstitium, microvascular, and metabolic abnormalities

Heart Failure With Preserved Ejection Fraction: Will Cardiac Magnetic Imaging Impact on Diagnosis, Treatment, and Outcomes?: Explaining the Need for Advanced Imaging to Clinical Stakeholders

Clinicians frequently equate symptoms of volume overload to heart failure (HF) but such generalization may preclude diagnostic or etiologic precision essential to optimizing outcomes. HF itself must be specified as the disparate types of cardiac pathology have been traditionally surmised by examination of left ventricular (LV) ejection fraction (EF) as either HF with preserved LVEF (HFpEF-LVEF >50%) or reduced LVEF of (HFrEF-LVEF <40%). More recent data support a third, potentially transitional HF subtype, but therapy, assessment, and prognosis have been historically dictated within the corresponding LV metrics determined by echocardiography. The present effort asks whether this historically dominant role of echocardiography is now shifting slightly, becoming instead a shared if not complimentary test. Will there be a gradual increasing profile for cardiac magnetic resonance as the attempt to further refine our understanding, diagnostic accuracy, and outcomes for HFpEF is attempted?

Heart failure with preserved ejection fraction: diagnosis, risk assessment, and treatment

The aetiology of heart failure with preserved ejection fraction (HFpEF) is heterogenous and overlaps with that of several comorbidities like atrial fibrillation, diabetes mellitus, chronic kidney disease, valvular heart disease, iron deficiency, or sarcopenia. The diagnosis of HFpEF involves evaluating cardiac dysfunction through imaging techniques and assessing increased left ventricular filling pressure, which can be measured directly or estimated through various proxies including natriuretic peptides. To better narrow down the differential diagnosis of HFpEF, European and American heart failure guidelines advocate the use of different algorithms including comorbidities that require diagnosis and rigorous treatment during the evaluation process. Therapeutic recommendations differ between guidelines. Whilst sodium glucose transporter 2 inhibitors have a solid evidence base, the recommendations differ with regard to the use of inhibitors of the renin-angiotensin-aldosterone axis. Unless indicated for specific comorbidities, the use of beta-blockers should be discouraged in HFpEF. The aim of this article is to provide an overview of the current state of the art in HFpEF diagnosis, clinical evaluation, and treatment.

Novel Strategies in Diagnosing Heart Failure with Preserved Ejection Fraction: A Comprehensive Literature Review

Heart failure (HF) with preserved ejection fraction (HFpEF) is a prevalent global condition affecting approximately 50% of the HF population. With the aging of the worldwide population, its incidence and prevalence are expected to rise even further. Unfortunately, until recently, no effective medications were available to reduce the high mortality and hospitalization rates associated with HFpEF, making it a significant unmet need in cardiovascular medicine. Although HFpEF is commonly defined as HF with normal ejection fraction and elevated left ventricular filling pressure, performing invasive hemodynamic assessments on every individual suspected of having HFpEF is neither feasible nor practical. Consequently, several clinical criteria and diagnostic tools have been proposed to aid in diagnosing HFpEF. Overall, these criteria and tools are designed to assist healthcare professionals in identifying and evaluating patients who may have HFpEF based on a combination of signs, symptoms, biomarkers, and non-invasive imaging findings. By employing these non-invasive diagnostic approaches, clinicians can make informed decisions regarding the best pharmacological and rehabilitation strategies for individuals with suspected HFpEF. This literature review aims to provide an overview of all currently available methods for diagnosing and monitoring this disabling condition.

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.

Pulmonary Hypertension Associated with Left Heart Disease

Pulmonary hypertension (PH) is a common complication of diseases affecting the left heart, mostly found in patients suffering from heart failure, with or without preserved left ventricular ejection fraction. Initially driven by a passive increase in left atrial pressure (postcapillary PH), several mechanisms may lead in a subset of patient to significant structural changes of the pulmonary vessels or a precapillary component. In addition, the right ventricle may be independently affected, which results in right ventricular to pulmonary artery uncoupling and right ventricular failure, all being associated with a worse outcome. The differential diagnosis of PH associated with left heart disease versus pulmonary arterial hypertension (PAH) is especially challenging in patients with cardiovascular comorbidities and/or heart failure with preserved ejection fraction (HFpEF). A stepwise approach to diagnosis is proposed, starting with a proper clinical multidimensional phenotyping to identify patients in whom hemodynamic confirmation is deemed necessary. Provocative testing (exercise testing, fluid loading, or simple leg raising) is useful in the cath laboratory to identify patients with abnormal response who are more likely to suffer from HFpEF. In contrast with group 1 PH, management of PH associated with left heart disease must focus on the treatment of the underlying condition. Some PAH-approved targets have been unsuccessfully tried in clinical studies in a heterogeneous group of patients, some even leading to an increase in adverse events. There is currently no approved therapy for PH associated with left heart disease.

Heart Failure Preserved Ejection Fraction in Women: Insights Learned from Imaging

While the prevalence of heart failure, in general, is similar in men and women, women experience a higher rate of HFpEF compared to HFrEF. Cardiovascular risk factors, parity, estrogen levels, cardiac physiology, and altered response to the immune system may be at the root of this difference. Studies have found that in response to increasing age and hypertension, women experience more concentric left ventricle remodeling, more ventricular and arterial stiffness, and less ventricular dilation compared to men, which predisposes women to developing more diastolic dysfunction. A multi-modality imaging approach is recommended to identify patients with HFpEF. Particularly, appreciation of sex-based differences as described in this review is important in optimizing the evaluation and care of women with HFpEF.

Imaging in Heart Failure with Preserved Ejection Fraction: A Multimodality Imaging Point of View

Heart failure with preserved ejection fraction (HFpEF) is an important global health problem. Despite increased prevalence due to improved diagnostic options, limited improvement has been achieved in cardiac outcomes. HFpEF is an extremely complex syndrome and multimodality imaging is important for diagnosis, identifying its different phenotypes and determining prognosis. Evaluation of left ventricular filling pressures using echocardiographic diastolic function parameters is the first step of imaging in clinical practice. The role of echocardiography is becoming more popular and with the recent developments in deformation imaging, cardiac MRI is extremely important as it can provide tissue characterisation, identify fibrosis and optimal volume measurements of cardiac chambers. Nuclear imaging methods can also be used in the diagnosis of specific diseases, such as cardiac amyloidosis.

Functional and Metabolic Imaging in Heart Failure with Preserved Ejection Fraction: Promises, Challenges, and Clinical Utility

Heart failure with preserved ejection fraction (HFpEF) is recognised as an increasingly prevalent, morbid and burdensome condition with a poor outlook. Recent advances in both the understanding of HFpEF and the technological ability to image cardiac function and metabolism in humans have simultaneously shone a light on the molecular basis of this complex condition of diastolic dysfunction, and the inflammatory and metabolic changes that are associated with it, typically in the context of a complex patient. This review both makes the case for an integrated assessment of the condition, and highlights that metabolic alteration may be a measurable outcome for novel targeted forms of medical therapy. It furthermore highlights how recent technological advancements and advanced medical imaging techniques have enabled the characterisation of the metabolism and function of HFpEF within patients, at rest and during exercise.

Heart failure: an update from the last years and a look at the near future

In the last years, major progress occurred in heart failure (HF) management. Quadruple therapy is now mandatory for all the patients with HF with reduced ejection fraction. Whilst verciguat is becoming available across several countries, omecamtiv mecarbil is waiting to be released for clinical use. Concurrent use of potassium-lowering agents may counteract hyperkalaemia and facilitate renin-angiotensin-aldosterone system inhibitor implementations. The results of the EMPagliflozin outcomE tRial in Patients With chrOnic heaRt Failure With Preserved Ejection Fraction (EMPEROR-Preserved) trial were confirmed by the Dapagliflozin in Heart Failure with Mildly Reduced or Preserved Ejection Fraction (DELIVER) trial, and we now have, for the first time, evidence for treatment of also patients with HF with preserved ejection fraction. In a pre-specified meta-analysis of major randomized controlled trials, sodium-glucose co-transporter-2 inhibitors reduced all-cause mortality, cardiovascular (CV) mortality, and HF hospitalization in the patients with HF regardless of left ventricular ejection fraction. Other steps forward have occurred in the treatment of decompensated HF. Acetazolamide in Acute Decompensated Heart Failure with Volume Overload (ADVOR) trial showed that the addition of intravenous acetazolamide to loop diuretics leads to greater decongestion vs. placebo. The addition of hydrochlorothiazide to loop diuretics was evaluated in the CLOROTIC trial. Torasemide did not change outcomes, compared with furosemide, in TRANSFORM-HF. Ferric derisomaltose had an effect on the primary outcome of CV mortality or HF rehospitalizations in IRONMAN (rate ratio 0.82; 95% confidence interval 0.66-1.02; P = 0.070). Further options for the treatment of HF, including device therapies, cardiac contractility modulation, and percutaneous treatment of valvulopathies, are summarized in this article.

Combined Neuro-Humoral Modulation and Outcomes in Patients with Chronic Heart Failure and Mildly Reduced or Preserved Ejection Fraction

Pharmacotherapy of chronic heart failure with mildly reduced (HFmrEF) and preserved ejection fraction (HFpEF) remains challenging. We aimed to assess whether combined neuro-humoral modulation (NHM) (renin−angiotensin system inhibitors, betablockers, mineralocorticoid receptor antagonists) was differentially associated with outcome according to phenotype and age groups. Between 1999 and 2018 we recruited in a nationwide cardiology registry 4707 patients (HFmrEF n = 2298, HFpEF n = 2409) from three age groups: <65, 65−79 and 80+ years old. We analyzed clinical characteristics and 1 year all-cause mortality/cardiovascular hospitalization according to none/single, any double, or triple NHM. Prescription rates of no/single and triple NHM were 25.1% and 26.7% for HFmrEF; 36.5% and 17.9% for HFpEF patients, respectively. Older age was associated with higher prescription of no/single NHM in HFmrEF (ptrend = 0.001); the reverse was observed among HFpEF (ptrend = 0.005). Triple NHM increased over time in both phenotypes (all p for trend < 0.0001). Compared to no/single NHM, triple, but not double, NHM was associated with better outcomes in both HFmrEF (HR 0.700, 95%CI 0.505−0.969, p = 0.032) and HFpEF (HR 0.700, 95%CI 0.499−0.983, p = 0.039), with no interaction between NHM treatment and age groups (p = 0.58, p = 0.80, respectively). In a cardiology setting, among HF outpatients with EF > 40%, triple NHM treatment increased over time and was associated with better patient outcomes.

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.

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.

Association of body mass index and prognosis in patients with HFpEF: A dose-response meta-analysis

BACKGROUND

Although agreements regarding the negative effects of obesity on the development of heart failure with preserved ejection fraction (HFpEF) have been reached, the relationship between body mass index (BMI) and adverse outcomes in HFpEF patients are still debatable. Therefore, we conducted the dose-response meta-analysis to investigate this relationship.

METHODS

We searched the PubMed and Embase databases up to February 2022 for studies that evaluated the association between BMI and prognostic outcomes in patients with HFpEF. A cubic spline random-effects model was used to fit the potential dose-response curve. The effect estimates were expressed as adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

A total of 11 studies involving 69,273 patients with HFpEF were included. The summary HR for all-cause mortality was 0.90 (95% CI, 0.84-0.95) per 5 units increase in BMI, but the association was U-shaped (P_nonlinear < 0.01) with the nadir of risk at a BMI of 32-34 kg/m². The summary HR for HF hospitalization was 1.12 (95% CI, 1.05-1.19) with a significant positive linear association (P_nonlinear = 0.54).

CONCLUSIONS

For patients with HFpEF, there was a positive linear association of BMI with HF hospitalization, while a U-shaped relationship between BMI and all-cause mortality was observed with the lowest event rate at a BMI of 32-34 kg/m².

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.

A year in heart failure: an update of recent findings

Major changes have occurred in these last years in heart failure (HF) management. Landmark trials and the 2021 European Society of Cardiology guidelines for the diagnosis and treatment of HF have established four classes of drugs for treatment of HF with reduced ejection fraction: angiotensin‐converting enzyme inhibitors or an angiotensin receptor‐neprilysin inhibitor, beta‐blockers, mineralocorticoid receptor antagonists, and sodium‐glucose co‐transporter 2 inhibitors, namely, dapagliflozin or empagliflozin. These drugs consistently showed benefits on mortality, HF hospitalizations, and quality of life. Correction of iron deficiency is indicated to improve symptoms and reduce HF hospitalizations. AFFIRM‐AHF showed 26% reduction in total HF hospitalizations with ferric carboxymaltose vs. placebo in patients hospitalized for acute HF (P = 0.013). The guanylate cyclase activator vericiguat and the myosin activator omecamtiv mecarbil improved outcomes in randomized placebo‐controlled trials, and vericiguat is now approved for clinical practice. Treatment of HF with preserved ejection fraction (HFpEF) was a major unmet clinical need until this year when the results of EMPEROR‐Preserved (EMPagliflozin outcomE tRial in Patients With chrOnic HFpEF) were issued. Compared with placebo, empagliflozin reduced by 21% (hazard ratio, 0.79; 95% confidence interval, 0.69 to 0.90; P < 0.001), the primary outcome of cardiovascular death or HF hospitalization. Advances in the treatment of specific phenotypes of HF, including atrial fibrillation, valvular heart disease, cardiomyopathies, cardiac amyloidosis, and cancer‐related HF, also occurred. Coronavirus disease 2019 (COVID‐19) pandemic still plays a major role in HF epidemiology and management. All these aspects are highlighted in this review.

Cardiovascular medicine: a year in review

Cardiovascular medicine is facing several challenges in the current era, dominated by the rapid spread of a previously unknown virus around the world. Indeed, the 2020 COVID-19 pandemic set the course of cardiovascular science and education in an extraordinary way, hogging the attention of the medical community. Notably, while COVID-19 impacted research progress, there has been considerable effort in exploring topics of great interest, from the management of acute coronary syndromes to new horizons in the treatment of heart failure, from novelties in the surgical treatment of cardiovascular disease to new data on implantable cardiac devices, and from new diagnostic applications of multimodal imaging techniques to relevant basic science findings. Minerva Cardiology and Angiology, formerly Minerva Cardioangiologica, has strived to inform its readers on these topics and novelties, aiming for a succinct yet poignant melding of timeliness and accuracy. Accordingly, the purpose of this narrative review is to highlight and summarize the major research and review articles published during 2020. In particular, we provide a broad overview of the novelties identifying six major areas of interest in the field of cardiovascular sciences in which new evidences have contributed to improving prevention, diagnosis and treatment of heart and vessels diseases.

Analysis of Characteristics of Patients with Non-ST-Segment Elevation Myocardial Infarction by Cardiac Magnetic Resonance Imaging

BACKGROUND In this study, cardiac magnetic resonance imaging was used to investigate the characteristics of patients who have total coronary occlusion but manifest with non-ST-segment elevation myocardial infarction (NSTEMI), and we assessed the extent of infarct transmurality and myocardial necrosis size in NSTEMI patients. MATERIAL AND METHODS We enrolled all patients diagnosed at our hospital with subtotal or total occlusion of the culprit artery (TOCA), based on the coronary angiography, who successfully underwent PCI within 12 h of admission, and who had CMR imaging performed within 2 days after the PCI. RESULTS Based on 12-lead ECG findings, 48% of patients were categorized as having STEMI and 52% as having NSTEMI. TOCA was detected by coronary angiography in 43% of NSTEMI patients, and in 60% and 33% of normal ST segment and ST-segment depression MI patients, respectively. The transmural segments were found in 78% of STEMI patients and 31% of NSTEMI patients (P<0.05). Transmural infarction segments were found in 64% of NSTEMI patients with TOCA and in 8% of NTOCA patients (P<0.05). Moreover, the number of transmural segments in ST-segment depression MI patients was the lowest (P<0.05). Infarct size in STEMI patients was significantly larger than in patients with NSTEMI (P<0.05), whereas there was no statistically significant difference in patients with normal ST segment and ST-segment depression MI patients (P>0.05). CONCLUSIONS Identification TOCA by coronary angiography and transmural infarction by DE-MRI can be challenging in AMI patients with non-ST-segment elevation. In approximately 30% of non-ST-segment elevation MI patients, transmural infarction was detected by DE-MRI. Therefore, TOCA accompanied by transmural infarction in non-ST-segment-elevation MI patients is not uncommon.

Myocardial Tissue Characterization in Heart Failure with Preserved Ejection Fraction: From Histopathology and Cardiac Magnetic Resonance Findings to Therapeutic Targets

Heart failure with preserved ejection fraction (HFpEF) is a complex clinical syndrome responsible for high mortality and morbidity rates. It has an ever growing social and economic impact and a deeper knowledge of molecular and pathophysiological basis is essential for the ideal management of HFpEF patients. The association between HFpEF and traditional cardiovascular risk factors is known. However, myocardial alterations, as well as pathophysiological mechanisms involved are not completely defined. Under the definition of HFpEF there is a wide spectrum of different myocardial structural alterations. Myocardial hypertrophy and fibrosis, coronary microvascular dysfunction, oxidative stress and inflammation are only some of the main pathological detectable processes. Furthermore, there is a lack of effective pharmacological targets to improve HFpEF patients' outcomes and risk factors control is the primary and unique approach to treat those patients. Myocardial tissue characterization, through invasive and non-invasive techniques, such as endomyocardial biopsy and cardiac magnetic resonance respectively, may represent the starting point to understand the genetic, molecular and pathophysiological mechanisms underlying this complex syndrome. The correlation between histopathological findings and imaging aspects may be the future challenge for the earlier and large-scale HFpEF diagnosis, in order to plan a specific and effective treatment able to modify the disease's natural course.

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

OBJECTIVES

This study examined the relationship among high-sensitivity troponin-T (hs-TnT), outcomes, and treatment with sacubitril/valsartan in patients with heart failure (HF) and preserved ejection fraction (HFpEF).

BACKGROUND

hs-TnT is a marker of myocardial injury in HF.

METHODS

The PARAGON-HF trial randomized 4,796 patients with HFpEF to sacubitril/valsartan or valsartan. We compared the risk of the composite outcome of cardiovascular death (CVD) and total HF hospitalization (HHF) according to hs-TnT. We also assessed the effect of allocated treatment on hs-TnT.

RESULTS

hs-TnT was available in 1,141 patients (24%) at run-in (median value: 17 ng/L) and 1,260 (26%) at randomization, with 58.3% having hs-TnT >14 ng/L (upper limit of normal). During a median follow-up of 34 months, there were 393 outcome events (82 CVD, 311 HHF). Adjusting for demographics, comorbidities, left ventricular ejection fraction (LVEF), and N-terminal pro B-type natriuretic peptide (NT-proBNP), log-hs-TnT at randomization was an independent predictor of the composite outcome (HR: 1.38; 95% CI: 1.19-1.59; P < 0.001). Compared with valsartan, sacubitril/valsartan significantly reduced hs-TnT by 9% at week 16 (P < 0.001). Patients whose hs-TnT decreased from randomization to 16 weeks to at or below the median value of 17 ng/L subsequently had a lower risk of CVD/HHF compared with those with persistently elevated hs-TnT (P = 0.046). Patients with higher baseline hs-TnT (>17 ng/L) appeared to have a greater benefit from sacubitril/valsartan treatment when accounting for other potential effect modifiers (P interaction = 0.07).

CONCLUSIONS

Higher baseline hs-TnT was associated with increased risk of CVD/HHF, whereas hs-TnT decrease at 16 weeks led to lower subsequent risk of CVD/HHF compared with those who had persistently elevated values. Sacubitril/valsartan significantly reduced hs-TnT compared with valsartan. hs-TnT may be helpful in identifying patients with HFpEF who are more likely to benefit from sacubitril/valsartan.

Myocardial Involvement in COVID-19: an Interaction Between Comorbidities and Heart Failure with Preserved Ejection Fraction. A Further Indication of the Role of Inflammation

PURPOSE OF THE REVIEW

Coronavirus Disease 2019 (COVID-19) and cardiovascular (CV) disease have a close relationship that emerged from the earliest reports. The aim of this review is to show the possible associations between COVID-19 and heart failure (HF) with preserved ejection fraction (HFpEF).

RECENT FINDINGS

In hospitalized patients with COVID-19, the prevalence of HFpEF is high, ranging from 4 to 16%, probably due to the shared cardio-metabolic risk profile. Indeed, comorbidities including hypertension, diabetes, obesity and chronic kidney disease - known predictors of a severe course of COVID-19 - are major causes of HFpEF, too. COVID-19 may represent a precipitating factor leading to acute decompensation of HF in patients with known HFpEF and in those with subclinical diastolic dysfunction, which becomes overt. COVID-19 may also directly or indirectly affect the heart. In otherwise healthy patients, echocardiographic studies showed that the majority of COVID-19 patients present diastolic (rather than systolic) impairment, pulmonary hypertension and right ventricular dysfunction. Such abnormalities are observed both in the acute or subacute phase of COVID-19. Cardiac magnetic resonance reveals myocardial inflammation and fibrosis in up to the 78% of patients in the chronic phase of the disease. These findings suggest that COVID-19 might be a novel independent risk factor for the development of HFpEF, through the activation of a systemic pro-inflammatory state. Follow-up studies are urgently needed to better understand long-term sequelae of COVID-19 inflammatory cardiomyopathy.

New Targets in Heart Failure Drug Therapy

Despite recent advances in chronic heart failure management (either pharmacological or non-pharmacological), the prognosis of heart failure (HF) patients remains poor. This poor prognosis emphasizes the need for developing novel pathways for testing new HF drugs, beyond neurohumoral and hemodynamic modulation approaches. The development of new drugs for HF therapy must thus necessarily focus on novel approaches such as the direct effect on cardiomyocytes, coronary microcirculation, and myocardial interstitium. This review summarizes principal evidence on new possible pharmacological targets for the treatment of HF patients, mainly focusing on microcirculation, cardiomyocyte, and anti-inflammatory therapy.

Current gaps in HFpEF trials: Time to reconsider patients' selection and to target phenotypes

Heart Failure with preserved Ejection Fraction (HFpEF) is an increasingly prevalent clinical condition associated with cardiovascular aging, characterized by different pathophysiological mechanisms and poor outcomes. In this manuscript, we analysed the main differences in terms of updated diagnostic criteria and patients' selection in the most recent HFpEF trials. Recent algorithm purposed for HFpEF diagnosis, does not reflect common criteria adopted in clinical trials. Patients included in the larger studies experienced different characteristics in terms of clinical presentation and echocardiographic features. Current concerns complicate results interpretation and could hypothesize different stages of disease progression, rather than different cardiac phenotypes. Both the lack of diagnostic standardization and the population heterogeneity, might explain why trials investigating the effects of different therapeutic interventions failed to show improved outcomes for patients with HFpEF. Accordingly, we propose to exceed current view mainly based on the morphological adaptations evaluating patients' characterisation, their cardiovascular risk, associated diseases, and structural features consistent with disease progression. Detailed clinical, imaging and biological characterisation of this population, along with the identification of mechanisms linked with disease progression and prognosis, would allow for tailored treatments and provide important mechanistic insights into the complex HFpEF pathophysiology.

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

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