The pathophysiology of heart failure with preserved ejection fraction

Prognostic value of the fibrinogen-to-albumin ratio (FAR) in patients with chronic heart failure across the different ejection fraction spectrum

The ratio of fibrinogen to albumin (FAR) is considered a new inflammatory biomarker and a predictor of cardiovascular disease risk. However, its prognostic value for patients with chronic heart failure (CHF) with different ejection fractions (EFs) remains unclear. A total of 916 hospitalized patients with CHF from January 2017 to October 2021 in the First Affiliated Hospital of Kunming Medical University were included in the study. Death occurred in 417 (45.5%) patients out of 916 patients during a median follow-up time of 750 days. Among these patients, 381 patients suffered from HFrEF (LVEF <40%) and 535 patients suffered from HFpEF or HFmrEF (HFpEF plus HFmrEF, LVEF ≥ 40%). Patients were categorized into high-level FAR (FAR-H) and low-level FAR (FAR-L) groups based on the optimal cut-off value of FAR (9.06) obtained from receiver operating characteristic (ROC) curve analysis. Upon analysing the Kaplan - Meier plots, the incidence of death was significantly higher in all patients with FAR-H and patients in both HF subgroups (p < 0.001). The multivariate Cox proportional hazard analyses indicated that the FAR was an independent predictor of all-cause mortality, regardless of heart failure subtype. (HR 1.115, 95% CI 1.089-1.142, p < 0.001; HFpEF plus HFmrEF, HR 1.109, 95% CI 1.074-1.146, p < 0.0001; HFrEF, HR 1.138, 95% CI 1.094-1.183, p < 0.0001) The optimal cut-off value of FAR in predicting all-cause mortality was 9.06 with an area under the curve value of 0.720 (95% CI: 0.687-0.753, p < 0.001), a sensitivity of 68.8% and a specificity of 65.6%. After adjusting for the traditional indicators (LVEF, Lg BNP, etc.), the new model with the FAR had better prediction ability in patients with CHF. Elevated FAR is an independent predictor of death in CHF and is not related to the HF subtype.

Diastolic Dysfunction of the Left and Right Ventricles in Patients with Calcium Pyrophosphate Crystal Storage Disease and Osteoarthritis

The frequency and risk factors for the development of diastolic dysfunction (DD) in patients with CPPD and OA have not been studied. The objective of this study was to determine the frequency and identify risk factors (RF) for the development of DD of the left and right ventricles (LV and RV) in patients with calcium pyrophosphate crystal deposition disease (CPPD) and osteoarthritis (OA). The study included 26 patients with CPPD and with knee OA 18-65 years old, matched in age and gender, without cardiovascular disease (CVD), type 2 diabetes mellitus (DM2), and rheumatic diseases. Conventional risk factors (TRF) of CVD were assessed, and echocardiography was performed. The frequency of DD in patients with CPPD and OA was quite high and almost did not differ in both groups: it was detected in 19 patients, of which 11 (42%) had CPPD and 8 (31%) had OA (p = 0.39). Type 1 LV DD was detected in 10 (39%) patients with CPPD and in 8 (31%) with OA (p = 0.11); type 1RV DD was detected in 8 (31%) patients with CPPD and in 7 (27%) patients with OA (p = 0.17); and type 1 LV DD and RV DD was detected in 7 (27%) patients with both CPPD and with OA. DD types 2 and 3 were not detected in both groups. There were no differences in both groups in CV risk factors, except for the level of CRP (it was higher in CPPD) (p = 0.03). In the CPPD group, mean values of LV E/E' (p = 0.02), LVDT (p = 0.03), LVMI (p = 0.04) were significantly higher than in patients with OA. On the contrary, in patients with OA, indices EDV (p = 0.004) and TVC (p = 0.02) were higher. There were direct correlations between diastolic function indices and the following factors in CPPD: LVL, PWLV and PTH level (r = 0.7, p <0.005), LV E' and PTH level (r = 0.7, p < 0.005). Inverse correlations were found between the level of PTH and IS (r = -0.5, p < 0.005), LVMI (r = -0.5, p < 0.005), and the level of vitamin D and VDDT (r = -0.6, p < 0.005). Direct correlations in OA were found between the level of CRP and PVAdiast (r = 0.6, p < 0.005), and the level of sUA (r = 0.7, p < 0.005), and the level of vitamin D and E/E'LV (r = 0.6, p < 0.005). A high prevalence of LV and RV DD was found in patients with CPPD and OA. The presence of DD in CPPD was associated with lower vitamin D levels, and in OA with a higher level of sUA and a lower level of PTH.

Self-adaptive deep learning-based segmentation for universal and functional clinical and preclinical CT image analysis

BACKGROUND

Methods to monitor cardiac functioning non-invasively can accelerate preclinical and clinical research into novel treatment options for heart failure. However, manual image analysis of cardiac substructures is resource-intensive and error-prone. While automated methods exist for clinical CT images, translating these to preclinical μCT data is challenging. We employed deep learning to automate the extraction of quantitative data from both CT and μCT images.

METHODS

We collected a public dataset of cardiac CT images of human patients, as well as acquired μCT images of wild-type and accelerated aging mice. The left ventricle, myocardium, and right ventricle were manually segmented in the μCT training set. After template-based heart detection, two separate segmentation neural networks were trained using the nnU-Net framework.

RESULTS

The mean Dice score of the CT segmentation results (0.925 ± 0.019, n = 40) was superior to those achieved by state-of-the-art algorithms. Automated and manual segmentations of the μCT training set were nearly identical. The estimated median Dice score (0.940) of the test set results was comparable to existing methods. The automated volume metrics were similar to manual expert observations. In aging mice, ejection fractions had significantly decreased, and myocardial volume increased by age 24 weeks.

CONCLUSIONS

With further optimization, automated data extraction expands the application of (μ)CT imaging, while reducing subjectivity and workload. The proposed method efficiently measures the left and right ventricular ejection fraction and myocardial mass. With uniform translation between image types, cardiac functioning in diastolic and systolic phases can be monitored in both animals and humans.

Proteomics of the heart

Mass spectrometry-based proteomics is a sophisticated identification tool specializing in portraying protein dynamics at a molecular level. Proteomics provides biologists with a snapshot of context-dependent protein and proteoform expression, structural conformations, dynamic turnover, and protein-protein interactions. Cardiac proteomics can offer a broader and deeper understanding of the molecular mechanisms that underscore cardiovascular disease, and it is foundational to the development of future therapeutic interventions. This review encapsulates the evolution, current technologies, and future perspectives of proteomic-based mass spectrometry as it applies to the study of the heart. Key technological advancements have allowed researchers to study proteomes at a single-cell level and employ robot-assisted automation systems for enhanced sample preparation techniques, and the increase in fidelity of the mass spectrometers has allowed for the unambiguous identification of numerous dynamic posttranslational modifications. Animal models of cardiovascular disease, ranging from early animal experiments to current sophisticated models of heart failure with preserved ejection fraction, have provided the tools to study a challenging organ in the laboratory. Further technological development will pave the way for the implementation of proteomics even closer within the clinical setting, allowing not only scientists but also patients to benefit from an understanding of protein interplay as it relates to cardiac disease physiology.

Effect of Left Ventricular Diastolic Dysfunction on the Cardiopulmonary Exercise Test in Patients With Cardiovascular Disease

Left ventricular diastolic dysfunction exists in patients with heart failure with reduced ejection fraction and causes activity restriction and a poor prognosis, but there have been few reports about exercise tolerance in patients with diastolic dysfunction, regardless of left ventricular ejection fraction (LVEF). In this study, 294 cardiovascular disease patients who performed a cardiopulmonary exercise test (CPX) with an adequate examination by echocardiography at Fukuoka University Hospital from 2011 to 2020 were investigated. Patients were divided into groups with grade I and grade II or III diastolic dysfunction according to diagnostic criteria, regardless of LVEF, by echocardiography. After adjusting for age, gender, body mass index, smoking, and LVEF by propensity score matching, we compared the results of CPX between the grade I and grade II/III groups. There were no significant differences in hemodynamic parameters, or in the respiratory exchange ratio, oxygen uptake per body weight, oxygen uptake per heart rate, or parameters of ventilatory volume. Ventilatory equivalents per oxygen uptake and per carbon dioxide output were significantly worse in the grade II/III group from the rest to peak periods during CPX. In conclusion, left ventricular diastolic dysfunction worsens ventilatory efficacy during CPX. This effect potentially contributes to a poor prognosis in left ventricular diastolic dysfunction.

Fractal analysis of left ventricular trabeculae in heart failure with preserved ejection fraction patients with multivessel coronary artery disease

OBJECTIVES

Endocardial trabeculae undergo varicose changes and hyperplasia in response to hemodynamic influences and are a variable phenotype reflecting changes in disease. Fractal analysis has been used to analyze the complexity of endocardial trabeculae in a variety of cardiomyopathies. The aim of this paper was to quantify the myocardial trabecular complexity through fractal analysis and to investigate its predictive value for the diagnosis of heart failure with preserved ejection fraction (HFpEF) in patients with multivessel coronary artery disease (CAD).

METHODS

The retrospective study population consisted of 97 patients with multivessel CAD, 39 of them were diagnosed with HFpEF, while 46 healthy volunteers were recruited as controls. Fractal dimension (FD) was obtained through fractal analysis of endocardial trabeculae on LV short-axis cine images. Logistic regression analyses were used to confirm the predictors and compare different prediction models.

RESULTS

Mean basal FD was significantly higher in patients with HFpEF than in patients without HFpEF or in the healthy group (median: 1.289; IQR: 0.078; p < 0.05). Mean basal FD was also a significant independent predictor in univariate and multivariate logistic regression (OR: 1.107 and 1.043, p < 0.05). Furthermore, adding FD to the prediction model improved the calibration and accuracy of the model (c-index: 0.806).

CONCLUSION

The left ventricular FD obtained with fractal analysis can reflect the complexity of myocardial trabeculae and has an independent predictive value for the diagnosis of HFpEF in patients with multivessel CAD. Including FD into the diagnostic model can help improve the diagnosis.

CRITICAL RELEVANCE STATEMENT

Differences show in the complexity of endocardial trabeculae in multivessel coronary artery disease patients, and obtaining fractal dimensions (FD) by fractal analysis can help identify heart failure with preserved ejection fraction (HFpEF) patients.

KEY POINTS

The complexity of myocardial trabeculae differs among patients with multivessel coronary artery disease. Left ventricular fractal dimensions can reflect the complexity of the myocardial trabecular. Fractal dimensions have predictive value for the diagnosis of heart failure with preserved ejection fraction.

Arterial Stiffness and Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is prevalent and associated with a poor prognosis, imposing a significant burden on society. Arterial stiffness is increasingly recognized as a crucial factor in the pathophysiology of HFpEF, affecting diagnosis, management, and prognosis. As a hallmark of vascular aging, arterial stiffness contributes to increased afterload on the left ventricle (LV), leading to diastolic dysfunction, a key feature of HFpEF. Elevated arterial stiffness is linked with common cardiovascular risk factors in HFpEF, such as hypertension, diabetes and obesity, exacerbating the progression of disease. Studies have demonstrated that patients with HFpEF exhibit significantly higher levels of arterial stiffness compared to those without HFpEF, highlighting the value of arterial stiffness measurements as both diagnostic and prognostic tools. Moreover, interventions aimed at reducing arterial stiffness, whether through pharmacological therapies or lifestyle modifications, have shown potential in improving LV diastolic function and patient outcomes. Despite these advancements, the precise mechanisms by which arterial stiffness contributes to HFpEF are still not fully understood, necessitating the need for further research.

Soft robotic platform for progressive and reversible aortic constriction in a small-animal model

Our understanding of cardiac remodeling processes due to left ventricular pressure overload derives largely from animal models of aortic banding. However, these studies fail to enable control over both disease progression and reversal, hindering their clinical relevance. Here, we describe a method for progressive and reversible aortic banding based on an implantable expandable actuator that can be finely tuned to modulate aortic banding and debanding in a rat model. Through catheterization, imaging, and histologic studies, we demonstrate that our platform can recapitulate the hemodynamic and structural changes associated with pressure overload in a controllable manner. We leveraged soft robotics to enable noninvasive aortic debanding, demonstrating that these changes can be partly reversed because of cessation of the biomechanical stimulus. By recapitulating longitudinal disease progression and reversibility, this animal model could elucidate fundamental mechanisms of cardiac remodeling and optimize timing of intervention for pressure overload.

Exploring the therapeutic potential of tetrahydrobiopterin for heart failure with preserved ejection fraction: A path forward

A large number of patients are affected by classical heart failure (HF) symptomatology with preserved ejection fraction (HFpEF) and multiorgan syndrome. Due to high morbidity and mortality rate, hospitalization and mortality remain serious socioeconomic problems, while the lack of effective pharmacological or device treatment means that HFpEF presents a major unmet medical need. Evidence from clinical and basic studies demonstrates that systemic inflammation, increased oxidative stress, and impaired mitochondrial function are the common pathological mechanisms in HFpEF. Tetrahydrobiopterin (BH4), beyond being an endogenous co-factor for catalyzing the conversion of some essential biomolecules, has the capacity to prevent systemic inflammation, enhance antioxidant resistance, and modulate mitochondrial energy production. Therefore, BH4 has emerged in the last decade as a promising agent to prevent or reverse the progression of disorders such as cardiovascular disease. In this review, we cover the clinical progress and limitations of using downstream targets of nitric oxide (NO) through NO donors, soluble guanylate cyclase activators, phosphodiesterase inhibitors, and sodium-glucose co-transporter 2 inhibitors in treating cardiovascular diseases, including HFpEF. We discuss the use of BH4 in association with HFpEF, providing new evidence for its potential use as a pharmacological option for treating HFpEF.

Urinary Proteomics and Outcomes in Heart Failure With Preserved Ejection Fraction

BACKGROUND

Although several studies have addressed plasma proteomics in heart failure with preserved ejection fraction, limited data are available on the prognostic value of urinary proteomics. The objective of our study was to identify urinary proteins/peptides associated with death and heart failure admission in patients with heart failure with preserved ejection fraction.

METHODS AND RESULTS

The study population included participants enrolled in TOPCAT (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist Trial). The relationship between urine protein levels and the risk of death or heart failure admission was assessed using Cox regression, in both nonadjusted analyses and adjusting for urine creatinine levels, and the MAGGIC (Meta-Analysis Global Group in Chronic Heart Failure) score. A total of 426 (12.4%) TOPCAT participants had urinary protein data and were included. There were 40 urinary proteins/peptides significantly associated with death or heart failure admission in nonadjusted analyses, 21 of which were also significant adjusted analyses. Top proteins in the adjusted analysis included ANGPTL2 (angiopoietin-like protein 2) (hazard ratio [HR], 0.5731 [95% CI, 0.47-0.7]; P=3.13E-05), AMY2A (α amylase 2A) (HR, 0.5496 [95% CI, 0.44-0.69]; P=0.0001), and DNASE1 (deoxyribonuclease-1) (HR, 0.5704 [95% CI, 0.46-0.71]; P=0.0002). Higher urinary levels of proteins involved in fibrosis (collagen VI α-1, collagen XV α-1), metabolism (pancreatic α-amylase 2A/B, mannosidase α class 1A member 1), and inflammation (heat shock protein family D member 1, inducible T cell costimulatory ligand) were associated with a lower risk of death or heart failure admission.

CONCLUSIONS

Our study identifies several novel associations between urinary proteins/peptides and outcomes in heart failure with preserved ejection fraction. Many of these associations are independent of clinical risk scores and may aid in risk stratification in this patient population.

Effects of short-term moderate intensity exercise on the serum metabolome in older adults: a pilot randomized controlled trial

BACKGROUND

We previously reported changes in the serum metabolome associated with impaired myocardial relaxation in an asymptomatic older community cohort. In this prospective parallel-group randomized control pilot trial, we subjected community adults without cardiovascular disease to exercise intervention and evaluated the effects on serum metabolomics.

METHODS

Between February 2019 to November 2019, thirty (83% females) middle-aged adults (53 ± 4 years) were randomized with sex stratification to either twelve weeks of moderate-intensity exercise training (Intervention) (n = 15) or Control (n = 15). The Intervention group underwent once-weekly aerobic and strength training sessions for 60 min each in a dedicated cardiac exercise laboratory for twelve weeks (ClinicalTrials.gov: NCT03617653). Serial measurements were taken pre- and post-intervention, including serum sampling for metabolomic analyses.

RESULTS

Twenty-nine adults completed the study (Intervention n = 14; Control n = 15). Long-chain acylcarnitine C20:2-OH/C18:2-DC was reduced in the Intervention group by a magnitude of 0.714 but increased in the Control group by a magnitude of 1.742 (mean difference -1.028 age-adjusted p = 0.004). Among Controls, alanine correlated with left ventricular mass index (r = 0.529, age-adjusted p = 0.018) while aspartate correlated with Lateral e' (r = -764, age-adjusted p = 0.016). C20:3 correlated with E/e' ratio fold-change in the Intervention group (r = -0.653, age-adjusted p = 0.004). Among Controls, C20:2/C18:2 (r = 0.795, age-adjusted p = 0.005) and C20:2-OH/C18:2-DC fold-change (r = 0.742, age-adjusted p = 0.030) correlated with change in E/A ratio.

CONCLUSIONS

Corresponding relationships between serum metabolites and cardiac function in response to exercise intervention provided pilot observations. Future investigations into cellular fuel oxidation or central carbon metabolism pathways that jointly impact the heart and related metabolic systems may be critical in preventive trials.

The Impact of SGLT2 Inhibitors on Cardiovascular Outcomes in Patients With Heart Failure With Preserved Ejection Fraction

OBJECTIVE

To evaluate the role of sodium-glucose cotransporter-2 (SGLT2) inhibitors in patients with heart failure with preserved ejection fraction (HFpEF).

DATA SOURCES

A literature search of PubMed, the Cochrane Library, and Google Scholar databases (January 2015 to June 20, 2023) was performed with keywords: sodium-glucose co-transporter 2 inhibitors OR SGLT2 inhibitors OR bexagliflozin OR canagliflozin OR dapagliflozin OR empagliflozin OR ertugliflozin OR sotagliflozin AND heart failure OR heart failure with preserved ejection fraction, and terms related to CV outcomes including cardiovascular death, hospitalization, hospitalization for heart failure, mortality, death, and major adverse cardiovascular event (MACE).

STUDY SELECTION AND DATA EXTRACTION

The reference list from retrieved articles as well as relevant review articles was considered. Pivotal randomized controlled trials and meta-analyses with a primary or secondary end point of CV death or heart failure hospitalization were included. Studies conducted solely in a diabetic patient population were excluded.

DATA SYNTHESIS

Dapagliflozin and empagliflozin, in a broad population of heart failure patients including, HFrEF, HFmrEF, HFpEF, and without diabetes, have shown consistent improvement in the combined outcome of CV death and hospitalization for heart failure (HR 0.80, 95% CI 0.73-0.87) and in the reduction of heart failure hospitalizations (HR 0.74, 95% CI 0.67-0.83). In patients with HFpEF, cardiovascular mortality was not demonstrated (HR 0.88, 95% CI 0.77-1.00). Rates of adverse events were low.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Patients with HFpEF and NYHA class II-III with frequent symptoms or hospitalizations for heart failure derive the most benefit from SGLT2 inhibitors with an overall goal of a reduction in heart failure hospitalizations.

CONCLUSIONS

The treatment of HFpEF has made progress, but there is still work to be done. Now, SGLT2 inhibitor therapy can be used to further help with symptom control and reduce overall hospitalizations for heart failure.

Drug Therapy for Acute and Chronic Heart Failure with Preserved Ejection Fraction with Hypertension: A State-of-the-Art Review

In this comprehensive state-of-the-art review, we provide an evidence-based analysis of current drug therapies for patients with heart failure with preserved ejection fraction (HFpEF) in the acute and chronic phases with concurrent hypertension. Additionally, we explore the latest developments and emerging evidence on the efficacy, safety, and clinical outcomes of common and novel drug treatments in the management of HFpEF with concurrent hypertension. During the acute phase of HFpEF, intravenous diuretics, mineralocorticoid receptor antagonists (MRAs), and vasodilators are pivotal, while in the chronic phase, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers have proven effective in enhancing clinical outcomes. However, the use of calcium channel blockers in HFpEF with hypertension should be approached with caution, owing to their potential negative inotropic effects. We also explored emerging drug therapies for HFpEF, such as sodium-glucose co-transporter 2 (SGLT2) inhibitors, angiotensin receptor-neprilysin inhibitor (ARNI), soluble guanylate cyclase (sGC) stimulators, novel MRAs, and ivabradine. Notably, SGLT2 inhibitors have shown promise in reducing heart failure hospitalizations and cardiovascular mortality in patients with HFpEF, regardless of their diabetic status. Additionally, ARNI and sGC stimulators have demonstrated potential in improving symptoms, functional capacity, and quality of life. Nonetheless, additional research is necessary to pinpoint optimal treatment strategies for HFpEF with concurrent hypertension. Furthermore, long-term studies are essential to assess the durability and sustained benefits of emerging drug therapies. Identification of novel targets and mechanisms underlying HFpEF pathophysiology will pave the way for innovative drug development approaches in the management of HFpEF with concurrent hypertension.

Characterisation of the octogenarians presenting to the diagnostic heart failure clinic: SHEAF registry

INTRODUCTION

Heart failure (HF) incidence is increasing in older adults with high hospitalisation and mortality rates. Treatment is complicated by side effects and comorbidities. We investigated the clinical characteristics of octogenarians presenting to the HF clinic.

METHODS

Data were collected on octogenarians (80-89 years) referred to the HF clinic in two periods. The data included demographics, HF phenotype, comorbidities, symptoms and treatment. We investigate the temporal changes in clinical characteristics using χ2 test. We aimed to determine the clinical characteristics which were associated with optimisation of HF pharmacological intervention in the clinic, conducting multivariate regression analysis. Statistical significance is determined at p<0.05.

RESULTS

Data were collected in April 2012 to January 2014 and in June 2021 to December 2022. In this cross-sectional study of temporal data, 571 octogenarians were referred to the clinic in the latter period, in whom the prevalence of HF was 68.48% (391 patients). HF with preserved ejection fraction (HFpEF) was the most common phenotype and increased significantly compared with the first period (46.3% and 29.2%, p<0.001). Frailty, chronic kidney disease and ischaemic heart disease increased significantly versus the first period (p<0.001). During the second period, and following the consultation, of the patients with HF with reduced ejection fraction (HFrEF), 86.4% and 82.7% were on a beta blocker and on an ACE inhibitor/angiotensin receptor blocker/angiotensin receptor-neprilysin inhibitor, respectively. Clinical characteristics associated with further optimisations of HF pharmacological therapy in the HF clinic were: New York Heart Association (NYHA) functional class III and the presence of HFrEF phenotype CONCLUSIONS: With a prevalence of HF at 68% among the octogenarians referred to the HF clinic, HFpEF incidence is rising. The decision to optimise HF pharmacological treatment in octogenarians is driven by NYHA functional class III and the presence of HFrEF phenotype.

Heart Failure With Preserved Ejection Fraction in the Elderly Population: Basic Mechanisms and Clinical Considerations

Heart failure with preserved ejection fraction (HFpEF) refers to a clinical condition in which the signs of heart failure, such as pulmonary congestion, peripheral edema, and increased natriuretic peptide levels, are present despite normal ejection fractions and the absence of other causes (eg, pericardial disease). The ejection fraction cutoff for the definition of HFpEF has varied in the past, but recent society guidelines have settled on a consensus of 50%. HFpEF is particularly common in the elderly population. The aim of this narrative review is to summarize the available literature regarding HFpEF in elderly patients in terms of evidence for the age dependence, specific clinical features, and underlying mechanisms. In the clinical arena, we review the epidemiology, discuss distinct clinical phenotypes typically seen in elderly patients, the importance of frailty, the role of biomarkers, and the role of medical therapies (including sodium-glucose cotransport protein 2 inhibitors, renin-angiotensin-aldosterone system blockers, angiotensin receptor/neprilysin inhibitors, diuretics, and β-adrenergic receptor blockers). We then go on to discuss the basic mechanisms implicated in HFpEF, including cellular senescence, fibrosis, inflammation, mitochondrial dysfunction, enhanced production of reactive oxygen species, abnormal cellular calcium handling, changes in microRNA signalling, insulin resistance, and sex hormone changes. Finally, we review knowledge gaps and promising areas of future investigation. Improved understanding of the specific clinical manifestations of HFpEF in elderly individuals and of the fundamental mechanisms that contribute to the age-related risk of HFpEF promises to lead to novel diagnostic and treatment approaches that will improve outcomes for this common cardiac disorder in a vulnerable population.

Titin: roles in cardiac function and diseases

The giant protein titin is an essential component of muscle sarcomeres. A single titin molecule spans half a sarcomere and mediates diverse functions along its length by virtue of its unique domains. The A-band of titin functions as a molecular blueprint that defines the length of the thick filaments, the I-band constitutes a molecular spring that determines cell-based passive stiffness, and various domains, including the Z-disk, I-band, and M-line, serve as scaffolds for stretch-sensing signaling pathways that mediate mechanotransduction. This review aims to discuss recent insights into titin's functional roles and their relationship to cardiac function. The role of titin in heart diseases, such as dilated cardiomyopathy and heart failure with preserved ejection fraction, as well as its potential as a therapeutic target, is also discussed.

Ambulatory Risk Stratification for Worsening Heart Failure in Patients with Reduced and Preserved Ejection Fraction Using Diagnostic Parameters Available in Implantable Cardiac Monitors

BACKGROUND

Ambulatory risk stratification for worsening heart failure (HF) using diagnostics measured by insertable cardiac monitors (ICM) may depend on the left ventricular ejection fraction (LVEF). We evaluated risk stratification performance in patients with reduced versus preserved LVEF.

METHODS

ICM patients with a history of HF events (HFEs) were included from the Optum® de-identified Electronic Health Record dataset merged with ICM device-collected data during 2007-2021. ICM measures nighttime heart rate (NHR), heart rate variability (HRV), atrial fibrillation (AF) burden, rate during AF, and activity duration (ACT) daily. Each diagnostic was categorized into high, medium, or low risk using previously defined features. HFEs were HF-related inpatient, observation unit, or emergency department stays with IV diuresis administration. Patients were divided into two cohorts: LVEF ≤ 40% and LVEF > 40%. A marginal Cox proportional hazards model compared HFEs for different risk groups.

RESULTS

A total of 1020 ICM patients with 18,383 follow-up months and 301 months with HFEs (1.6%) were included. Monthly evaluations with a high risk were 2.3, 4.2, 5.0, and 4.5 times (p < 0.001 for all) more likely to have HFEs in the next 30 days compared to those with a low risk for AF, ACT, NHR, and HRV, respectively. HFE rates were higher for patients with LVEF > 40% compared to LVEF ≤ 40% (2.0% vs. 1.3%), and the relative risk between high-risk and low-risk for each diagnostic parameter was higher for patients with LVEF ≤ 40%.

CONCLUSIONS

Diagnostics measured by ICM identified patients at risk for impending HFEs. Patients with preserved LVEF showed a higher absolute risk, and the relative risk between risk groups was higher in patients with reduced LVEF.

Distinguishing heart failure with reduced ejection fraction from heart failure with preserved ejection fraction: A phenomics approach

AIM

Pathophysiological differences between patients with heart failure with preserved (HFpEF) and reduced (HFrEF) ejection fraction (EF) remain unclear. Therefore we used a phenomics approach, integrating selected proteomics data with patient characteristics and cardiac structural and functional parameters, to get insight into differential pathophysiological mechanisms and identify potential treatment targets.

METHODS AND RESULTS

We report data from a representative subcohort of the prospective Singapore Heart Failure Outcomes and Phenotypes (SHOP), including patients with HFrEF (EF <40%, n = 217), HFpEF (EF ≥50%, n = 213), and age- and sex-matched controls without HF (n = 216). We measured 92 biomarkers using a proximity extension assay and assessed cardiac structure and function in all participants using echocardiography. We used multi-block projection to latent structure analysis to integrate clinical, echocardiographic, and biomarker variables. Candidate biomarker targets were cross-referenced with small-molecule and drug databases. The total cohort had a median age of 65 years (interquartile range 60-71), and 50% were women. Protein profiles strongly discriminated patients with HFrEF (area under the curve [AUC] = 0.89) and HFpEF (AUC = 0.94) from controls. Phenomics analyses identified unique druggable inflammatory markers in HFpEF from the tumour necrosis factor receptor superfamily (TNFRSF), which were positively associated with hypertension, diabetes, and increased posterior and relative wall thickness. In HFrEF, interleukin (IL)-8 and IL-6 were possible targets related to lower EF and worsening renal function.

CONCLUSION

We identified pathophysiological mechanisms related to increased cardiac wall thickness parameters and potentially druggable inflammatory markers from the TNFRSF in HFpEF.

Comparative analysis of ventricular stiffness across species

Investigating ventricular diastolic properties is crucial for understanding the physiological cardiac functions in organisms and unraveling the pathological mechanisms of cardiovascular disorders. Ventricular stiffness, a fundamental parameter that defines ventricular diastolic functions in chordates, is typically analyzed using the end-diastolic pressure-volume relationship (EDPVR). However, comparing ventricular stiffness accurately across chambers of varying maximum volume capacities has been a long-standing challenge. As one of the solutions to this problem, we propose calculating a relative ventricular stiffness index by applying an exponential approximation formula to the EDPVR plot data of the relationship between ventricular pressure and values of normalized ventricular volume by the ventricular weight. This article reviews the potential, utility, and limitations of using normalized EDPVR analysis in recent studies. Herein, we measured and ranked ventricular stiffness in differently sized and shaped chambers using ex vivo ventricular pressure-volume analysis data from four animals: Wistar rats, red-eared slider turtles, masu salmon, and cherry salmon. Furthermore, we have discussed the mechanical effects of intracellular and extracellular viscoelastic components, Titin (Connectin) filaments, collagens, physiological sarcomere length, and other factors that govern ventricular stiffness. Our review provides insights into the comparison of ventricular stiffness in different-sized ventricles between heterologous and homologous species, including non-model organisms.

Heart failure with preserved ejection fraction: everything the clinician needs to know

Heart failure with preserved ejection fraction (HFpEF) is increasingly recognised and diagnosed in clinical practice, a trend driven by an ageing population and a rise in contributing comorbidities, such as obesity and diabetes. Representing at least half of all heart failure cases, HFpEF is recognised as a complex clinical syndrome. Its diagnosis and management are challenging due to its diverse pathophysiology, varied epidemiological patterns, and evolving diagnostic and treatment approaches. This Seminar synthesises the latest insights on HFpEF, integrating findings from recent clinical trials, epidemiological research, and the latest guideline recommendations. We delve into the definition, pathogenesis, epidemiology, diagnostic criteria, and management strategies (non-pharmacological and pharmacological) for HFpEF. We highlight ongoing clinical trials and future developments in the field. Specifically, this Seminar offers practical guidance tailored for primary care practitioners, generalists, and cardiologists who do not specialise in heart failure, simplifying the complexities in the diagnosis and management of HFpEF. We provide practical, evidence-based recommendations, emphasising the importance of addressing comorbidities and integrating the latest pharmacological treatments, such as SGLT2 inhibitors.

First-phase ejection fraction to predict adverse outcomes in patients with heart failure

BACKGROUND

First-phase ejection fraction (EF1) is a novel measurement of early left ventricular systolic dysfunction. We investigate its prognostic value in patients with heart failure (HF).

METHODS AND RESULTS

Patients with HF were prospectively enrolled from July 2019 to September 2021. A total of 228 patients were included in the final analysis. The primary endpoint was the composite of all-cause mortality or rehospitalization for HF, which occurred in 74 patients (32.46%). EF1 as well as other parameters for left ventricular function were measured in echocardiography. Time-dependent ROC showed the cutoff value of EF1 was 18.55%. Kaplan-Meier analysis indicated a higher rate of adverse events in the lower EF1 group (EF1 ≤ 18.55%) (Log-rank test P < 0.001). Cox regression analyses showed EF1 was an independent predictor with adverse events as a continuous variable (Cox model 1: per 1% change in EF1: HR = 0.92, 95%CI: 0.87-0.97, P < 0.001), as well as a categorical variable (Cox model 2: EF1 > 18.55%: HR = 0.21, 95%CI: 0.08-0.53, P < 0.001) after adjustment for hypertension, coronary artery disease (CAD), Log10 (NT-proBNP), eGFR, E/e' and loop diuretics. Restricted cubic splines revealed a linear association between EF1 levels and the incidence of adverse events (P for non-linearity = 0.145). The subgroup analyses showed the predictive ability of elevated EF1 on the decreased risk of adverse events did not change substantially stratified by HF classification, age, CAD and hypertension.

CONCLUSION

EF1, as a novel measurement of early systolic function, is a promising predictor of adverse events among HF patients. EF1 might be considered a new measurement for risk stratification of HF.

Low-grade systemic inflammation and left ventricular dysfunction in hypertensive compared to non-hypertensive hypertrophic cardiomyopathy

BACKGROUND

Arterial hypertension (HTN) is associated with excess mortality in hypertrophic cardiomyopathy (HCM), but underlying mechanisms are largely elusive. The objective of this study was to investigate the association between HTN and markers of left ventricular (LV) dysfunction and low-grade systemic inflammation in a HCM cohort.

METHODS

This was a single-center cross-sectional case-control study comparing echocardiographic and plasma-derived indices of LV dysfunction and low-grade systemic inflammation between 30 adult patients with HCM and HTN (HTN+) and 30 sex- and age-matched HCM patients without HTN (HTN-). Echocardiographic measures were assessed using post-processing analyses by blinded investigators.

RESULTS

Mean age of the study population was 55.1 ± 10.4 years, 30% were women. Echocardiographic measures of systolic and diastolic dysfunction, including speckle-tracking derived parameters, did not differ between HTN+ and HTN-. Moreover, levels of N-terminal pro B-type natriuretic peptide were balanced between cases and controls. Compared with HTN-, HTN+ patients exhibited a higher white blood cell count [8.1 ± 1.8 109/l vs. 6.4 ± 1.6 109/l; p < 0.001] as well as higher plasma levels of interleukin-6 [2.8 pg/ml (2.0, 5.4) vs. 2.1 pg/ml (1.5, 3.4); p = 0.008] and high-sensitivity C-reactive protein [2.6 mg/l (1.4, 6.5) vs. 1.1 mg/l (0.9, 2.4); p = 0.004].

CONCLUSION

This study demonstrates that HTN is associated with indices of low-grade systemic inflammation among HCM patients. Moreover, this analysis indicates that the adverse impact of HTN in HCM patients is a consequence of systemic effects rather than alterations of cardiac function, as measures of LV systolic and diastolic dysfunction did not differ between HTN+ and HTN-.

Preload dependence in an animal model of mild heart failure with preserved ejection fraction (HFpEF)

AIM

Heart Failure with preserved Ejection Fraction (HFpEF) is characterized by diastolic dysfunction and reduced cardiac output, but its pathophysiology remains poorly understood. Animal models of HFpEF are challenging due to difficulties in assessing the degree of heart failure in small animals. This study aimed at inducing HFpEF in a mouse model to probe preload-dependency.

METHODS

Increased body mass and arterial hypertension were induced in mice using a Western diet and NO synthase inhibition. Preload dependence was tested ex vivo.

RESULTS

Mice with obesity and hypertension exhibited reduced cardiac output, indicating a failing heart. Increased left ventricular filling pressure during diastole suggested reduced compliance. Notably, the ejection fraction was preserved, suggesting the development of HFpEF. Spontaneous physical activity at night was reduced in HFpEF mice, indicating exercise intolerance; however, the cardiac connective tissue content was comparable between HFpEF and control mice. The HFpEF mice showed increased vulnerability to reduced preload ex vivo, indicating that elevated left ventricular filling pressure compensated for the rigid left ventricle, preventing a critical decrease in cardiac output.

CONCLUSION

This animal model successfully developed mild HFpEF with a reduced pump function that was dependent on a high preload. A model of mild HFpEF may serve as a valuable tool for studying disease progression and interventions aimed at delaying or reversing symptom advancement, considering the slow development of HFpEF in patients.

Running on empty: Factors underpinning impaired cardiac output reserve in heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is frequently attributed etiologically to an underlying left ventricular (LV) diastolic dysfunction, although its pathophysiology is far more complex and can exhibit significant variations among patients. This review endeavours to systematically unravel the pathophysiological heterogeneity by illustrating diverse mechanisms leading to an impaired cardiac output reserve, a central and prevalent haemodynamic abnormality in HFpEF patients. Drawing on previously published findings from our research group, we propose a pathophysiology-guided phenotyping based on the presence of: (1) LV diastolic dysfunction, (2) LV systolic pathologies, (3) arterial stiffness, (4) atrial impairment, (5) right ventricular dysfunction, (6) tricuspid valve regurgitation, and (7) chronotopic incompetence. Tailored to each specific phenotype, we explore various potential treatment options such as antifibrotic medication, diuretics, renal denervation and more. Our conclusion underscores the pivotal role of cardiac output reserve as a key haemodynamic abnormality in HFpEF, emphasizing that by phenotyping patients according to its individual pathomechanisms, insights into personalized therapeutic approaches can be gleaned.

Pathophysiological insights into machine learning-based subphenotypes of acute heart failure with preserved ejection fraction

OBJECTIVE

The heterogeneous pathophysiology of the diverse heart failure with preserved ejection fraction (HFpEF) phenotypes needs to be examined. We aim to assess differences in the biomarkers among the phenotypes of HFpEF and investigate its multifactorial pathophysiology.

METHODS

This study is a retrospective analysis of the PURSUIT-HFpEF Study (N=1231), an ongoing, prospective, multicentre observational study of acute decompensated HFpEF. In this registry, there is a predefined subcohort in which we perform multibiomarker tests (N=212). We applied the previously established machine learning-based clustering model to the subcohort with biomarker measurements to classify them into four phenotypes: phenotype 1 (n=69), phenotype 2 (n=49), phenotype 3 (n=41) and phenotype 4 (n=53). Biomarker characteristics in each phenotype were evaluated.

RESULTS

Phenotype 1 presented the lowest value of N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitive C reactive protein, tumour necrosis factor-α, growth differentiation factor (GDF)-15, troponin T and cystatin C, whereas phenotype 2, which is characterised by hypertension and cardiac hypertrophy, showed the highest value of these markers. Phenotype 3 showed the second highest value of GDF-15 and cystatin C. Phenotype 4 presented a low NT-proBNP value and a relatively high GDF-15.

CONCLUSIONS

Distinctive characteristics of biomarkers in HFpEF phenotypes would indicate differential underlying mechanisms to be elucidated. The contribution of inflammation to the pathogenesis varied considerably among different HFpEF phenotypes. Systemic inflammation substantially contributes to the pathophysiology of the classic HFpEF phenotype with cardiac hypertrophy.

TRIAL REGISTRATION NUMBER

UMIN-CTR ID: UMIN000021831.

Early Renal Denervation Attenuates Cardiac Dysfunction in Heart Failure With Preserved Ejection Fraction

BACKGROUND

The renal sympathetic nervous system modulates systemic blood pressure, cardiac performance, and renal function. Pathological increases in renal sympathetic nerve activity contribute to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). We investigated the effects of renal sympathetic denervation performed at early or late stages of HFpEF progression.

METHODS AND RESULTS

Male ZSF1 obese rats were subjected to radiofrequency renal denervation (RF-RDN) or sham procedure at either 8 weeks or 20 weeks of age and assessed for cardiovascular function, exercise capacity, and cardiorenal fibrosis. Renal norepinephrine and renal nerve tyrosine hydroxylase staining were performed to quantify denervation following RF-RDN. In addition, renal injury, oxidative stress, inflammation, and profibrotic biomarkers were evaluated to determine pathways associated with RDN. RF-RDN significantly reduced renal norepinephrine and tyrosine hydroxylase content in both study cohorts. RF-RDN therapy performed at 8 weeks of age attenuated cardiac dysfunction, reduced cardiorenal fibrosis, and improved endothelial-dependent vascular reactivity. These improvements were associated with reductions in renal injury markers, expression of renal NLR family pyrin domain containing 3/interleukin 1β, and expression of profibrotic mediators. RF-RDN failed to exert beneficial effects when administered in the 20-week-old HFpEF cohort.

CONCLUSIONS

Our data demonstrate that early RF-RDN therapy protects against HFpEF disease progression in part due to the attenuation of renal fibrosis and inflammation. In contrast, the renoprotective and left ventricular functional improvements were lost when RF-RDN was performed in later HFpEF progression. These results suggest that RDN may be a viable treatment option for HFpEF during the early stages of this systemic inflammatory disease.

Endothelial Senescence: From Macro- to Micro-Vasculature and Its Implications on Cardiovascular Health

Endothelial cells line at the most inner layer of blood vessels. They act to control hemostasis, arterial tone/reactivity, wound healing, tissue oxygen, and nutrient supply. With age, endothelial cells become senescent, characterized by reduced regeneration capacity, inflammation, and abnormal secretory profile. Endothelial senescence represents one of the earliest features of arterial ageing and contributes to many age-related diseases. Compared to those in arteries and veins, endothelial cells of the microcirculation exhibit a greater extent of heterogeneity. Microcirculatory endothelial senescence leads to a declined capillary density, reduced angiogenic potentials, decreased blood flow, impaired barrier properties, and hypoperfusion in a tissue or organ-dependent manner. The heterogeneous phenotypes of microvascular endothelial cells in a particular vascular bed and across different tissues remain largely unknown. Accordingly, the mechanisms underlying macro- and micro-vascular endothelial senescence vary in different pathophysiological conditions, thus offering specific target(s) for therapeutic development of senolytic drugs.

Chapter 2: Clinical and Mechanistic Potential of Sodium-Glucose Co-Transporter 2 (SGLT2) Inhibitors in Heart Failure with Preserved Ejection Fraction

Sodium-glucose co-transporter 2 inhibitors (SGLT2i) have emerged as an important approach for the treatment of heart failure in patients with or without diabetes. Although the precise mechanisms underpinning their clinical impact remain incompletely resolved, mechanistic studies and insights from major clinical trials have demonstrated the impact of SGLT2 inhibitors on numerous cardio-renal-metabolic pathways of relevance to heart failure with preserved ejection fraction (HFpEF), which, in the contemporary era, constitutes approximately half of all patients with heart failure. Despite rates of morbidity and mortality that are commensurate with those of heart failure with reduced ejection fraction, disease-modifying therapies have comparatively been severely lacking. As such, HFpEF remains among the greatest unmet needs in cardiovascular medicine. Within the past decade, HFpEF has been established as a highly integrated disorder, involving not only the cardiovascular system, but also the lungs, kidneys, skeletal muscle, and adipose tissue. Given their multisystem impact, SGLT2i offer unique promise in addressing the complex pathophysiology of HFpEF, and in recent randomized controlled trials, were shown to significantly reduce heart failure events and cardiovascular death in patients with HFpEF. Herein, we discuss several proposed mechanisms of clinical benefit of SGLT2i in HFpEF.

Urinary Marker Profiles in Heart Failure with Reduced Versus Preserved Ejection Fraction

BACKGROUND

Recent data suggest different causes of renal dysfunction between heart failure with reduced (HFrEF) versus preserved ejection fraction (HFpEF). We therefore studied a wide range of urinary markers reflecting different nephron segments in heart failure patients.

METHODS

In 2070, in chronic heart failure patients, we measured several established and upcoming urinary markers reflecting different nephron segments.

RESULTS

Mean age was 70 ± 12 years, 74% was male and 81% (n = 1677) had HFrEF. Mean estimated glomerular filtration rate (eGFR) was lower in patients with HFpEF (56 ± 23 versus 63 ± 23 ml/min/1.73 m2, P = 0.001). Patients with HFpEF had significantly higher values of NGAL (58.1 [24.0-124.8] versus 28.1 [14.6-66.9] μg/gCr, P < 0.001) and KIM-1 (2.28 [1.49-4.37] versus 1.79 [0.85-3.49] μg/gCr, P = 0.001). These differences were more pronounced in patients with an eGFR > 60 ml/min/1.73m2.

CONCLUSIONS

HFpEF patients showed more evidence of tubular damage and/or dysfunction compared with HFrEF patients, in particular when glomerular function was preserved.

Heart Failure with Preserved Ejection Fraction: The Pathophysiological Mechanisms behind the Clinical Phenotypes and the Therapeutic Approach

Heart failure (HF) with preserved ejection fraction (HFpEF) is an increasingly frequent form and is estimated to be the dominant form of HF. On the other hand, HFpEF is a syndrome with systemic involvement, and it is characterized by multiple cardiac and extracardiac pathophysiological alterations. The increasing prevalence is currently reaching epidemic levels, thereby making HFpEF one of the greatest challenges facing cardiovascular medicine today. Compared to HF with reduced ejection fraction (HFrEF), the medical attitude in the case of HFpEF was a relaxed one towards the disease, despite the fact that it is much more complex, with many problems related to the identification of physiopathogenetic mechanisms and optimal methods of treatment. The current medical challenge is to develop effective therapeutic strategies, because patients suffering from HFpEF have symptoms and quality of life comparable to those with reduced ejection fraction, but the specific medication for HFrEF is ineffective in this situation; for this, we must first understand the pathological mechanisms in detail and correlate them with the clinical presentation. Another important aspect of HFpEF is the diversity of patients that can be identified under the umbrella of this syndrome. Thus, before being able to test and develop effective therapies, we must succeed in grouping patients into several categories, called phenotypes, depending on the pathological pathways and clinical features. This narrative review critiques issues related to the definition, etiology, clinical features, and pathophysiology of HFpEF. We tried to describe in as much detail as possible the clinical and biological phenotypes recognized in the literature in order to better understand the current therapeutic approach and the reason for the limited effectiveness. We have also highlighted possible pathological pathways that can be targeted by the latest research in this field.

Non-coding RNAs in the pathophysiology of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) is the largest unmet clinical need in cardiovascular medicine. Despite decades of research, the treatment option for HFpEF is still limited, indicating our ongoing incomplete understanding on the underlying molecular mechanisms. Non-coding RNAs, comprising of microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), are non-protein coding RNA transcripts, which are implicated in various cardiovascular diseases. However, their role in the pathogenesis of HFpEF is unknown. Here, we discuss the role of miRNAs, lncRNAs and circRNAs that are involved in the pathophysiology of HFpEF, namely microvascular dysfunction, inflammation, diastolic dysfunction and cardiac fibrosis. We interrogated clinical evidence and dissected the molecular mechanisms of the ncRNAs by looking at the relevant in vivo and in vitro models that mimic the co-morbidities in patients with HFpEF. Finally, we discuss the potential of ncRNAs as biomarkers and potential novel therapeutic targets for future HFpEF treatment.

Artificial intelligence-enabled ECG for left ventricular diastolic function and filling pressure

Assessment of left ventricular diastolic function plays a major role in the diagnosis and prognosis of cardiac diseases, including heart failure with preserved ejection fraction. We aimed to develop an artificial intelligence (AI)-enabled electrocardiogram (ECG) model to identify echocardiographically determined diastolic dysfunction and increased filling pressure. We trained, validated, and tested an AI-enabled ECG in 98,736, 21,963, and 98,763 patients, respectively, who had an ECG and echocardiographic diastolic function assessment within 14 days with no exclusion criteria. It was also tested in 55,248 patients with indeterminate diastolic function by echocardiography. The model was evaluated using the area under the curve (AUC) of the receiver operating characteristic curve, and its prognostic performance was compared to echocardiography. The AUC for detecting increased filling pressure was 0.911. The AUCs to identify diastolic dysfunction grades ≥1, ≥2, and 3 were 0.847, 0.911, and 0.943, respectively. During a median follow-up of 5.9 years, 20,223 (20.5%) died. Patients with increased filling pressure predicted by AI-ECG had higher mortality than those with normal filling pressure, after adjusting for age, sex, and comorbidities in the test group (hazard ratio (HR) 1.7, 95% CI 1.645-1.757) similar to echocardiography and in the indeterminate group (HR 1.34, 95% CI 1.298-1.383). An AI-enabled ECG identifies increased filling pressure and diastolic function grades with a good prognostic value similar to echocardiography. AI-ECG is a simple and promising tool to enhance the detection of diseases associated with diastolic dysfunction and increased diastolic filling pressure.

Coagulation Disorders and Thrombotic Complications in Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is associated with multiple cardiovascular and noncardiovascular comorbidities and risk factors which increase the risk of thrombotic complications, such as atrial fibrillation, chronic kidney disease, arterial hypertension and type 2 diabetes mellitus. Subsequently, thromboembolic risk stratification in this population poses a great challenge. Since date from the large randomized clinical trials mostly include both patients with truly preserved EF, and those with heart failure with mildly reduced ejection fraction, there is an unmet need to characterize the patients with truly preserved EF. Considering the significant evidence gap in this area, we sought to describe the coagulation disorders and thrombotic complications in patients with HFpEF and discuss the specific thromboembolic risk factors in patients with HFpEF, with the goal to tailor risk stratification to an individual patient.

Cholinesterase inhibitors associated with lower rate of mortality in dementia patients with heart failure: a nationwide propensity weighting study

PURPOSE

This study investigates the potential impact of cholinesterase inhibitors (ChEIs) on patients with heart failure (HF) and dementia. ChEIs are known to boost acetylcholine levels and benefit cognition in patients with dementia; however, their effect on patients with HF is uncertain. This study aimed to assess whether cardiovascular events and mortality among patients with HF and dementia are altered by ChEI therapy.

METHODS

Data from the National Health Insurance Research Database in Taiwan were retrospectively analyzed. Dementia patients diagnosed with HF were followed for 5 years until all-cause mortality, cardiovascular mortality, hospitalization for worsening HF, or the end of the study. Multivariable Cox models and inverse probability of treatment weighting (IPTW) were employed.

RESULTS

Out of 20,848 patients with dementia, 5138 had HF. Among them, 726 were ChEI users and 4412 were non-users. Based on IPTW, the ChEI users had significantly lower estimated risks of all-cause mortality [hazard ratio (HR) 0.43; 95% confidence interval (CI) 0.38-0.49, p < 0.001] and cardiovascular mortality (HR 0.41; 95% CI 0.33-0.53, p < 0.001) compared with the non-users, but there was no significant difference in hospitalization for worsening HF (HR 0.73; 95% CI 0.51-1.05, p = 0.091) after 5 years. The survival benefits of ChEIs were consistent across subgroups.

CONCLUSIONS

The results of this retrospective cohort study suggest that ChEIs may be beneficial in reducing all-cause and cardiovascular mortality in patients with dementia with HF. Further research is needed to validate these findings and explore the potential benefits of ChEIs in all patients with HF, including those without dementia.

Syndromes of Concurrent Hypertension, Diastolic Dysfunction, and Pulmonary or Peripheral Edema in Cardio-Oncology: Case Studies, Literature Review, and New Classification System

OPINION STATEMENT

Individuals who have ever been diagnosed with cancer are at increased risk for cardiovascular conditions during and after cancer treatment. Especially during cancer treatment, cardiovascular conditions can manifest in many ways, including peripheral or pulmonary edema. Edema can indicate volume overload affecting the heart even without other unequivocal evidence of apparent diastolic or systolic left ventricular dysfunction, particularly at rest. We propose a novel algorithm to streamline the diagnostic evaluation and cardiovascular classification for cancer patients with edema. We initially advise prompt evaluation with a chest X-ray and echocardiogram. We then suggest classification into one of five categories based on the timing of presentation of edema relative to cancer treatment, as well as echocardiography results and the presence or absence of hypertension or lymphatic causes of edema. This classification tool can then be utilized to guide further cardiovascular management suggestions. These concurrent syndromes presenting as edema may indicate the development or aggravation of undiagnosed diastolic dysfunction with or without hypertension, even if transiently present only while on cancer treatment.

Hypertensive response to exercise, hypertension and heart failure with preserved ejection fraction (HFpEF)-a continuum of disease?

INTRODUCTION

Heart failure with preserved ejection fraction (HFpEF) has been shown to be a long-term consequence of uncontrolled arterial hypertension (aHT). Other than that, hypertensive response to exercise (HRE) precedes aHT. We aim to evaluate the available evidence for a continuum of HRE, aHT and HFpEF.

METHODS

A literature search on PubMed was conducted to assembly the most recent data on the topic. After collecting the data, a qualitative analysis was instrumented.

RESULTS

10 studies including 16,165 subjects were analyzed with respect to the association between HRE and the future risk of developing aHT. With the exception of one study, all reported on a positive association between HRE and the future development of aHT despite methodological issues related to different definitions for HRE. Furthermore, HRE was associated with an increased risk of coronary artery disease. Moreover, we analysed 6 studies including overall 1366 subjects investigating the association between HRE and HFpEF. In these studies, increased left atrial volume index (LAVI), elevated E/e' (as surrogate parameters of increased LV end-diastolic filling pressure and of diastolic dysfunction) and higher LV mass index have been proposed as independent predictor of HRE in patients with no known HFpEF diagnosis.

DISCUSSION AND CONCLUSION

The literature search revealed suggestive data on a connection of HRE, aHT and HFpEF. HRE seems to be an independent risk factor for aHT and aHT in turn is one of the main risk factors for HFpEF. However, further research is needed to improve our knowledge of a possible continuum of disease.

Effects of beta-blocker withdrawal in patients with heart failure with preserved ejection fraction: A protocol for systematic review and meta-analysis

BACKGROUND

The primary chronic symptom of patients with heart failure with preserved ejection fraction (HFpEF) is severe exercise intolerance. The inability to adequately increase heart rate during exercise (chronotropic incompetence) is commonly present in HFpEF patients and contributes importantly to exercise intolerance in these patients. Since HFpEF patients often have cardiac comorbidities such as hypertension, coronary artery disease, and atrial fibrillation, beta-blockers are frequently prescribed for the treatment of these comorbidities. However, there is a concern that beta-blockers may worsen chronotropic incompetence by slowing heart rate in HFpEF patients and may further exacerbate their symptoms. There are several studies on the effects of beta-blocker withdrawal in HFpEF patients. We aim to perform the systematic review and meta-analysis of studies on the effects of beta-blocker withdrawal in HFpEF patients.

METHODS

This meta-analysis will include randomized controlled trials and prospective cohort studies on the effect of beta-blocker withdrawal in HFpEF patients. Information of studies will be collected from PubMed, Web of Science, and Scopus. The primary outcome will be peak oxygen uptake (peak VO2). The secondary outcome will be 6-minute walk distance. Other outcomes of interest will be health-related quality of life, plasma BNP levels, and cardiac structure and function.

DISCUSSION

This systematic review and meta-analysis will evaluate whether beta-blocker withdrawal is beneficial for HFpEF patients, providing evidence regarding beta-blocker withdrawal in these patients.

TRIAL REGISTRATION

Systematic review registration: INPLASY202370066.

Cardiac rehabilitation utilization, barriers, and outcomes among patients with heart failure

Exercise-based cardiac rehabilitation (CR) is effective for improving both primary (i.e., mortality and hospitalizations) and secondary (i.e., functional capacity and quality of life among) clinical outcomes among patients with heart failure (HF). The mechanisms that explain these benefits are complex and are linked to exercise adaptations such as central and peripheral hemodynamics combined with improved overall medical management. Despite the benefits of CR, utilization rates are low among CR eligible patients. Clinician-, patient-, and health system-related barriers have been identified as primary factors contributing to the lack of CR utilization among HF patients. These include patient referrals (clinician-related), psychosocial factors (patient-related), and patient access to CR services (health system-related). The aims of this review are to detail the components of each barrier as well as identify evidence-based strategies to improve CR utilization and adherence among HF. The improvements in primary and secondary outcomes along with the mechanisms that are linked to these changes will also be examined.

Searching for Effective Treatments in HFpEF: Implications for Modeling the Disease in Rodents

BACKGROUND

While the prevalence of heart failure with preserved ejection fraction (HFpEF) has increased over the last two decades, there still remains a lack of effective treatment. A key therapeutic challenge is posed by the absence of animal models that accurately replicate the complexities of HFpEF. The present review summarizes the effects of a wide spectrum of therapeutic agents on HF.

METHODS

Two online databases were searched for studies; in total, 194 experimental protocols were analyzed following the PRISMA protocol.

RESULTS

A diverse range of models has been proposed for studying therapeutic interventions for HFpEF, with most being based on pressure overload and systemic hypertension. They have been used to evaluate more than 150 different substances including ARNIs, ARBs, HMGR inhibitors, SGLT-2 inhibitors and incretins. Existing preclinical studies have primarily focused on LV diastolic performance, and this has been significantly improved by a wide spectrum of candidate therapeutic agents. Few experiments have investigated the normalization of pulmonary congestion, exercise capacity, animal mortality, or certain molecular hallmarks of heart disease.

CONCLUSIONS

The development of comprehensive preclinical HFpEF models, with multi-organ system phenotyping and physiologic stress-based functional testing, is needed for more successful translation of preclinical research to clinical trials.

Long-Term Cumulative High-Sensitivity C-Reactive Protein and Mortality Among Patients With Acute Heart Failure

Background Elevated hsCRP (high-sensitivity C-reactive protein) level is associated with worse prognosis among patients hospitalized for heart failure. However, the prognostic value of the long-term cumulative hsCRP remains unknown. Methods and Results We consecutively enrolled patients hospitalized for heart failure and collected their hsCRP data at admission and 1 and 12 months after discharge. Long-term cumulative hsCRP was evaluated using 2 approaches, cumulative hsCRP level quartiles and cumulative times of high hsCRP levels. Patients were classified into 4 groups by cumulative hsCRP level quartiles and cumulative times of high hsCRP levels (0- to 3-times: number of times that hsCRP levels were higher than cutoff values at admission or 1 or 12 months), respectively. Multivariable Cox models were used to assess the association of mortality with cumulative hsCRP. A total of 1281 patients were included; the median age was 64 (interquartile range, 54-73) years, and 35.4% were women. Over a 4.8-year (interquartile range, 4.2-5.1) follow-up, 374 (29.2%) patients died. Elevated long-term cumulative hsCRP level was related to higher mortality. Specifically, taking the quartile 1 as the reference, the hazard ratios (HRs) were 1.29 (95% CI, 0.92-1.81) for quartile 2, 1.62 (95% CI, 1.16-2.25) for quartile 3, and 2.38 (95% CI, 1.75-3.23) for quartile 4. Similarly, compared with the patients with 0-times (hsCRP level lower than the cutoff values in all 3 time points) of high hsCRP level, the HRs were 1.36 for 1-time (hsCRP level higher than the cutoff value in one of the 3 time points) (95% CI, 0.92-2.01), 1.95 for 2-times (hsCRP levels higher than the cutoff values in 2 of the 3 time points) (95% CI, 1.34-2.82), and 2.80 for 3-times (hsCRP levels higher than the cutoff values in the 3 time points) (95% CI, 1.97-4.00). Conclusions Increasing long-term cumulative hsCRP level was associated with worse outcomes in patients hospitalized for acute heart failure. Repeated hsCRP measurements could assist physicians in identifying patients with a high risk of death. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02878811.

Intraventricular 4D flow cardiovascular magnetic resonance for assessing patients with heart failure with preserved ejection fraction: a pilot study

Diagnosing heart failure with preserved ejection fraction (HFpEF) remains challenging. Intraventricular four-dimensional flow (4D flow) phase-contrast cardiovascular magnetic resonance (CMR) can assess different components of left ventricular (LV) flow including direct flow, delayed ejection, retained inflow and residual volume. This could be utilised to identify HFpEF. This study investigated if intraventricular 4D flow CMR could differentiate HFpEF patients from non-HFpEF and asymptomatic controls. Suspected HFpEF patients and asymptomatic controls were recruited prospectively. HFpEF patients were confirmed using European Society of Cardiology (ESC) 2021 expert recommendations. Non-HFpEF patients were diagnosed if suspected HFpEF patients did not fulfil ESC 2021 criteria. LV direct flow, delayed ejection, retained inflow and residual volume were obtained from 4D flow CMR images. Receiver operating characteristic (ROC) curves were plotted. 63 subjects (25 HFpEF patients, 22 non-HFpEF patients and 16 asymptomatic controls) were included in this study. 46% were male, mean age 69.8 ± 9.1 years. CMR 4D flow derived LV direct flow and residual volume could differentiate HFpEF vs combined group of non-HFpEF and asymptomatic controls (p < 0.001 for both) as well as HFpEF vs non-HFpEF patients (p = 0.021 and p = 0.005, respectively). Among the 4 parameters, direct flow had the largest area under curve (AUC) of 0.781 when comparing HFpEF vs combined group of non-HFpEF and asymptomatic controls, while residual volume had the largest AUC of 0.740 when comparing HFpEF and non-HFpEF patients. CMR 4D flow derived LV direct flow and residual volume show promise in differentiating HFpEF patients from non-HFpEF patients.

Factors Affecting Biochemical and Echocardiographic Indices in Type 2 Diabetes Mellitus Patients Without Overt Symptoms of Heart Failure: A Cross-Sectional Study

Introduction Diabetes is a known risk factor for heart failure (HF), and HF often manifests as a common cardiovascular event in people with type-2 diabetes mellitus (T2DM). Once HF is present, diabetes presents an especially adverse prognosis for subsequent morbidity and mortality. Brain natriuretic peptide (BNP) and n-terminal ProBNP (NT-proBNP) are used as diagnostic biomarkers for HF that are secreted by the ventricles in response to increased myocardial wall stress. If we could unmask some clinical and routine laboratory parameters affecting BNP and ejection fraction (EF), we can predict impending HF and take measures to prevent it. The current study was conducted to investigate the factors affecting BNP and EF for detecting potential HF in T2DM patients who do not exhibit overt HF symptoms. Materials and methods The present cross-sectional study was performed after obtaining ethical clearance from the Institutional Ethics Committee. T2DM patients consulting the Medicine Outpatient Department (OPD) of BRD Medical College Gorakhpur during a two-month period (from 20 July 2023 to 19 September 2023) with age >40 years and duration of T2DM >10 years. Multistage random sampling was done to recruit study participants, and 308 patients participated in the study. Informed consent was obtained from the recruited participants. The chi-square or Fisher's exact test (whichever was applicable) was used to explore the association between categorical variables. Correlation statistics were calculated using Spearman correlation among the NT-proBNP, EF, and other relevant variables. The Statistical Package for Social Sciences (SPSS) (version 21; IBM SPSS Statistics for Windows, Armonk, NY) was used for the analysis, and a two-sided p-value of < 0.05 was considered significant. Results Three hundred and eight diabetic patients satisfying inclusion and exclusion criteria were enrolled as study participants and completed the study. The mean age of the total study subjects was 60.82 ± 9.23 years. There were 161 (52.3%) male and 147 (47.7%) female participants, and about half (153/308, 49.7%) of the participants belonged to the age group 40-60 years. There was a statistically significant association (p = 0.01) between NT-proBNP and glycated hemoglobin. Statistically highly significant (p < 0.001) associations were found between NT-proBNP with duration of T2DM and EF. There was a strong negative correlation (correlation coefficient = -0.743) between EF and NT-proBNP, and this correlation was statistically highly significant with a p-value < 0.001. Conclusion Elevated NT-proBNP levels and impaired EF were found in a significant proportion of these patients, indicating an increased risk of cardiovascular complications. This study highlights a significant association between NT-proBNP and EF in patients with T2DM in those without overt heart failure symptoms. Furthermore, longer T2DM duration and higher HbA1c levels were found to be associated with elevated NT-proBNP levels, while longer T2DM duration and elevated NT-proBNP were linked to lower EF. These findings have important clinical implications, as they suggest that monitoring NT-proBNP levels in patients with T2DM without clinical features of overt heart failure may help identify those at risk for decreased EF and potentially prevent heart failure.

Sizing SGLT2 Inhibitors Up: From a Molecular to a Morpho-Functional Point of View

Sodium-glucose cotransporter 2 inhibitors (SGLT2i), or gliflozins, have recently been shown to reduce cardiovascular death and hospitalization in patients with heart failure, representing a revolutionary therapeutic tool. The purpose of this review is to explore their multifaceted mechanisms of actions, beyond their known glucose reduction power. The cardioprotective effects of gliflozins seem to be linked to the maintenance of cellular homeostasis and to an action on the main metabolic pathways. They improve the oxygen supply for cardiomyocytes with a considerable impact on both functional and morphological myocardial aspects. Moreover, multiple molecular actions of SGLT2i are being discovered, such as the reduction of both inflammation, oxidative stress and cellular apoptosis, all responsible for myocardial damage. Various studies showed controversial results concerning the role of SGLT2i in reverse cardiac remodeling and the lowering of natriuretic peptides, suggesting that their overall effect has yet to be fully understood. In addition to this, advanced imaging studies evaluating the effect on all four cardiac chambers are lacking. Further studies will be needed to better understand the real impact of their administration, their use in daily practice and how they can contribute to benefits in terms of reverse cardiac remodeling.

Cardiac and Metabolic Effects of Dapagliflozin in Heart Failure With Preserved Ejection Fraction: The CAMEO-DAPA Trial

BACKGROUND

Sodium-glucose cotransporter-2 inhibitors reduce risk of hospitalization for heart failure in patients who have heart failure with preserved ejection fraction (HFpEF), but the hemodynamic mechanisms underlying these benefits remain unclear. This study sought to determine whether treatment with dapagliflozin affects pulmonary capillary wedge pressure (PCWP) at rest and during exercise in patients with HFpEF.

METHODS

This was a single-center, double-blinded, randomized, placebo-controlled trial testing the effects of 10 mg of dapagliflozin once daily in patients with HFpEF. Patients with New York Heart Association class II or III heart failure, ejection fraction ≥50%, and elevated PCWP during exercise were recruited. Cardiac hemodynamics were measured at rest and during exercise using high-fidelity micromanometers at baseline and after 24 weeks of treatment. The primary end point was a change from baseline in rest and peak exercise PCWPs that incorporated both measurements, and was compared using a mixed-model likelihood ratio test. Key secondary end points included body weight and directly measured blood and plasma volumes. Expired gas analysis was performed evaluate oxygen transport in tandem with arterial lactate sampling.

RESULTS

Among 38 patients completing baseline assessments (median age 68 years; 66% women; 71% obese), 37 completed the trial. Treatment with dapagliflozin resulted in reduction in the primary end point of change in PCWP at rest and during exercise at 24 weeks relative to treatment with placebo (likelihood ratio test for overall changes in PCWP; P<0.001), with lower PCWP at rest (estimated treatment difference [ETD], -3.5 mm Hg [95% CI, -6.6 to -0.4]; P=0.029) and maximal exercise (ETD, -5.7 mm Hg [95% CI, -10.8 to -0.7]; P=0.027). Body weight was reduced with dapagliflozin (ETD, -3.5 kg [95% CI, -5.9 to -1.1]; P=0.006), as was plasma volume (ETD, -285 mL [95% CI, -510 to -60]; P=0.014), but there was no significant effect on red blood cell volume. There were no differences in oxygen consumption at 20-W or peak exercise, but dapagliflozin decreased arterial lactate at 20 W (-0.70 ± 0.77 versus 0.37 ± 1.29 mM; P=0.006).

CONCLUSIONS

In patients with HFpEF, treatment with dapagliflozin reduces resting and exercise PCWP, along with the favorable effects on plasma volume and body weight. These findings provide new insight into the hemodynamic mechanisms of benefit with sodium-glucose cotransporter-2 inhibitors in HFpEF.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04730947.

Comparative effects of nebivolol and carvedilol on left ventricular diastolic function in older patients with heart failure and preserved ejection fraction

Background

Although many studies have compared carvedilol and nebivolol in heart failure (HF) patients with reduced left ventricular ejection fraction (LVEF), such comparative studies for the elderly have not been reported yet. Nebivolol is known to be effective for improving diastolic function of elderly patients with HF. Thus, this study aimed to determine whether nebivolol could improve LV diastolic function to a greater extent than carvedilol in older patients aged over 70 years.

Methods

This trial was a prospective, randomized, open-label, single-center, active-controlled study that enrolled 62 patients with class II or III HF over 70 years of age with an LVEF ≥40%. Patients were randomized into a carvedilol group or a nebivolol group. Transthoracic echocardiography was performed at baseline and 12 months by the same investigator who was blinded to clinical data. The primary endpoint was E/e' measured by echocardiographic evaluation 12 months after treatment.

Results

The median duration of follow-up was 24 months. Baseline clinical characteristics and echocardiographic parameters, such as LV diastolic function indices, did not differ significantly between carvedilol and nebivolol groups. Twelve-month follow-up echocardiography data showed no significant difference in E/e' or other LV diastolic function indices between the two groups. There were no significant changes in echocardiographic parameters over 12 months in either group.

Conclusions

There was no difference between carvedilol and nebivolol for improving diastolic function of elderly HF patients with LVEF ≥40%. This study showed no superiority of nebivolol over carvedilol in elderly patients with HF.

Heart Failure With Preserved Ejection Fraction: An Evolving Understanding

Heart failure (HF) with preserved ejection fraction (HFpEF) is a clinical syndrome in which patients have signs and symptoms of HF due to high left ventricular (LV) filling pressure despite normal or near normal LV ejection fraction. It is more common than HF with reduced ejection fraction (HFrEF), and its diagnosis and treatment are more challenging than HFrEF. Although hypertension is the primary risk factor, coronary artery disease and other comorbidities, such as atrial fibrillation (AF), diabetes, chronic kidney disease (CKD), and obesity, also play an essential role in its formation. This review summarizes current knowledge about HFpEF, its pathophysiology, clinical presentation, diagnostic challenges, current treatments, and promising novel treatments. It is essential to continue to be updated on the latest treatments for HFpEF so that patients always receive the most therapeutic treatments. The use of GnRH agonists in the management of HFpEF, infusion of Apo a-I nanoparticle, low-level transcutaneous vagal stimulation (LLTS), and estrogen only in post-menopausal women are promising strategies to prevent diastolic dysfunction and HFpEF; however, there is still no proven curative treatment for HFpEF yet.

Electronic health record characterization and outcomes of heart failure with preserved ejection fraction

BACKGROUND

Electronic health record (EHR)-based identification of heart failure with preserved ejection fraction (HFpEF) in the clinical setting may facilitate screening for clinical trials by improving the understanding of its epidemiology and outcomes; yet, previous data have yielded variable results. We sought to characterize groups identified with HFpEF by different EHR screening strategies and their associated long-term outcomes across a large and diverse population.

METHODS

We retrospectively analyzed 116,499 consecutive patients from an academic referral center who underwent echocardiography, and 9,263 patients who underwent echocardiography within 6 months of right heart catheterization (RHC), between 2008 and 2018. EHR-based screening strategies identified patients with HFpEF using 1) International Classification of Diseases (ICD)-9/10 codes, 2) H2FpEF score ≥6 and ejection fraction (EF) ≥50%, or 3) RHC wedge pressure ≥15 mmHg and EF ≥50%, when available. Primary outcomes were 1) cumulative incident heart failure hospitalization (HFH), and 2) death, over 10 years.

RESULTS

There were 33,461 (29%) patients who met either ICD or H2FpEF-HFpEF definition, of whom 5,310 (16%) met both criteria. Compared to ICD-HFpEF, patients with H2FpEF-HFpEF were more likely older (median age 72 vs 67), White (78% vs 64%), and had atrial fibrillation (97% vs 41%). Among those also with RHC, 6,353 (69%) patients met any HFpEF criteria, of whom only 783 (12%) satisfied all three criteria. Female sex was more common among RHC-HFpEF (55%) compared to other methods (H2FpEF-HFpEF, 47%; ICD-HFpEF, 43%). Atrial fibrillation was substantially higher among HFpEF identified by the H2FpEF score (97%) compared to other methods (49% for ICD and 47% for RHC). Across HFpEF screening methods, 10-year cumulative incidence rates for HFH was 32% to 45% for echocardiography only and 43% to 52% for echocardiography and RHC populations; 10-year risk of death was 54% to 56% for echocardiography only and 52% to 57% for echocardiography and RHC populations.

CONCLUSIONS

Different EHR-based HFpEF definitions identified cohorts with modest overlap and varying baseline characteristics. Yet, long-term risk for HFH and death were similarly high for cohorts identified among both populations undergoing echocardiography only or echocardiography and RHC. These data aid in identifying relevant subgroups in clinical trials of HFpEF.