Characteristics of Heart Failure With Preserved Ejection Fraction Across the Range of Left Ventricular Ejection Fraction

Supra-normal and mildly reduced ejection fraction in women -An overlooked vulnerable subpopulation in heart failure

BACKGROUND

Recently, patients with supra-normal left ventricular ejection fraction (snEF) are reported to have high risk of adverse outcomes, especially in women. We sought to evaluate sex-related differences in the association between LVEF and long-term outcomes in heart failure (HF) patients.

METHODS

The multicenter WET-HF Registry enrolled all patients hospitalized for acute decompensated HF (ADHF). We analyzed 3943 patients (age 77 years; 40.1% female) registered from 2006 to 2017. According to LVEF the patients were divided into the 3 groups: HF with reduced EF (HFrEF), mildly reduced EF (HFmrEF) and preserved EF. The primary endpoint was defined as the composite of cardiac death and ADHF rehospitalization after discharge.

RESULTS

In HFmrEF, implementation of guideline-directed medical therapy (GDMT) such as the combination of renin-angiotensin-system inhibitor (RASi) and β-blocker at discharge was significantly lower in women than men even after adjustment for covariates (p = 0.007). There were no such sex-related differences in HFrEF. Female sex was associated with higher incidence of the primary endpoint and ADHF rehospitalization after adjustment for covariates exclusively in HFmrEF. Restricted cubic spline analysis demonstrated a U-shaped relationship between LVEF and the hazard ratio of the primary endpoint showing higher event rate in HFmrEF and HFsnEF in women, but such relationship was not observed in men (p for interaction = 0.037).

CONCLUSIONS

In women, mrEF and snEF were associated with worse long-term outcomes. Additionally, sex-related differences in the GDMT implementation for HFmrEF highlight the need for further exploration, which might lead to creation of sex-specific guidelines to optimize HF management.

Clinical Significance of Exercise Pulmonary Hypertension With a Negative Diastolic Stress Test for Suspected Heart Failure With Preserved Ejection Fraction

BACKGROUND

Half of patients with heart failure with preserved ejection fraction (HFpEF) remain undiagnosed by resting evaluation alone. Therefore, exercise testing is proposed. The diastolic stress test (DST), however, has limited sensitivity. We aimed to determine the clinical significance of adding the mean pulmonary artery pressure over cardiac output (mPAP/CO) slope to the DST in suspected HFpEF.

METHODS AND RESULTS

In this prospective cohort study, consecutive patients (n=1936) with suspected HFpEF underwent exercise echocardiography with simultaneous respiratory gas analysis. These patients were stratified by exercise E over e' (exE/e') and mPAP/CO slope, and peak oxygen uptake, natriuretic peptides (NT-proBNP [N-terminal pro-B-type natriuretic peptide]), and score-based HFpEF likelihood were compared. Twenty-two percent of patients (n=428) had exE/e'<15 despite a mPAP/CO slope>3 mm Hg/L per min, 24% (n=464) had a positive DST (exE/e'≥15), and 54% (n=1044) had a normal DST and slope. Percentage of predicted oxygen uptake was similar in the group with exE/e'<15 but high mPAP/CO slope and the positive DST group (-2% [-5% to +1%]), yet worse than in those with normal DST and slope (-12% [-14% to -9%]). Patients with exE/e'<15 but a high slope had NT-proBNP levels and H2FPEF (heavy, hypertensive, atrial fibrillation, pulmonary hypertension, elder; filling pressure) scores intermediate to the positive DST group and the group with both a normal DST and slope.

CONCLUSIONS

Twenty-two percent of patients with suspected HFpEF presented with a mPAP/CO slope>3 mm Hg/L per min despite a negative DST. These patients had HFpEF characteristics and a peak oxygen uptake as low as patients with a positive DST. Therefore, an elevated mPAP/CO slope might indicate HFpEF irrespective of the DST result.

Left ventricular volume and maximal functional capacity in heart failure with preserved ejection fraction: Size matters

AIMS

Emerging evidence suggests that smaller left ventricular volumes may identify subjects with lower cardiorespiratory fitness. Whether left ventricular size predicts functional capacity in patients with heart failure with preserved ejection fraction (HFpEF) is unclear. This study aimed to explore the association between indexed left ventricular end-diastolic volume (iLVEDV) and maximal functional capacity, assessed by peak oxygen consumption (peakVO2), in stable outpatients with HFpEF.

METHODS AND RESULTS

We prospectively analysed data from 133 consecutive stable outpatients who underwent cardiopulmonary exercise testing and echocardiography on the same day. Data were validated in a cohort of HFpEF patients from San Paolo Hospital, Milan, Italy. A multivariable linear regression assessed the association between iLVEDV and peakVO2. The mean age was 73.2 ± 10.5 years, and 75 (56.4%) were women. The median iLVEDV, indexed left ventricular end-systolic volume, and left ventricular ejection fraction were 46 ml/m2 (30-56), 15 ml/m2 (11-19), and 66% (60-74%), respectively. The median peakVO2 and percentage of predicted peakVO2 were 11 ml/kg/min (9-13) and 64.1% (53-74.4), respectively. Adjusted linear regression analysis showed that smaller iLVEDV was associated with lower peakVO2 (p = 0.0001). In the validation cohort, adjusted linear regression analysis showed a consistent pattern: a smaller iLVEDV was associated with a higher likelihood of reduced peakVO2 (p = 0.004).

CONCLUSIONS

In stable outpatients with HFpEF, a smaller iLVEDV was associated with a lower maximal functional capacity. These findings suggest a need for further studies to understand the pathophysiological mechanisms underlying these observations and to explore targeted treatment strategies for this patient subgroup.

NEW INSIGHTS INTO CARDIOPROTECTION IN BREAST CANCER PATIENTS UNDERGOING PHYSICAL EXERCISE DURING CHEMOTHERAPY: A SYSTEMATIC REVIEW AND META-ANALYSIS

BACKGROUND

Chemotherapy associated with breast cancer often induces cardiotoxicity, which compromises patients' health and quality of life.

OBJECTIVE

To verify the effect of physical exercise on chemotherapy-induced cardiotoxicity, through the assessment of cardiac function in patients with breast cancer.

METHODS

Systematic review and meta-analysis of clinical studies to evaluate the effectiveness of physical training in chemotherapy-induced cardiomyopathy in the PubMed, Web of Sciences and Scopus databases. Thirteen studies were included in the systematic review and eleven studies in the data meta-analysis.

RESULTS

Global longitudinal strain presents a cardioprotective effect when compared to the control group (Heterogeneity: Chi² = 12.81, df = 10 (p = 0.23); I² = 22%.) Test for global effect: Z = 2, 13 (p = 0.03). Physical training is more effective (test for subgroup differences, p = 0.031) in attenuating the impairment of %GLS induced by chemotherapy if performed concomitantly with exposure to chemotherapy (95% CI; Heterogeneity: Chi² = 7.49, gl = 5 (p = 0.19); I² = 33%; Test for global effect: Z = 2.33 (p = 0.02) when compared after chemotherapy treatment, or in the long term (for 12 months or more). However, without benefits in LVEF (Heterogeneity: Chi² = 42.14, df = 10 (p < 0.00001); I² = 76%) Test for global effect: Z = 2.51 (p = 0.01) Conclusion: Exercise training is a cardioprotective approach in breast cancer patients who experience chemotherapy-induced cardiotoxicity. Exercise during exposure to chemotherapy has greater effects on preserving cardiac function.

Endothelin-1 influences mechanical properties and contractility of hiPSC derived cardiomyocytes resulting in diastolic dysfunction

A better understanding of the underlying pathomechanisms of diastolic dysfunction is crucial for the development of targeted therapeutic options with the aim to increase the patients' quality of life. In order to shed light on the processes involved, suitable models are required. Here, effects of endothelin-1 (ET-1) treatment on cardiomyocytes derived from human induced pluripotent stem cells (hiPSCs) were investigated. While it is well established, that ET-1 treatment induces hypertrophy in cardiomyocytes, resulting changes in cell mechanics and contractile behavior with focus on relaxation have not been examined before. Cardiomyocytes were treated with 10 nM of ET-1 for 24 h and 48 h, respectively. Hypertrophy was confirmed by real-time deformability cytometry (RT-DC) which was also used to assess the mechanical properties of cardiomyocytes. For investigation of the contractile behavior, 24 h phase contrast video microscopy was applied. To get a deeper insight into changes on the molecular biological level, gene expression analysis was performed using the NanoString nCounter® cardiovascular disease panel. Besides an increased cell size, ET-1 treated cardiomyocytes are stiffer and show an impaired relaxation. Gene expression patterns in ET-1 treated hiPSC derived cardiomyocytes showed that pathways associated with cardiovascular diseases, cardiac hypertrophy and extracellular matrix were upregulated while those associated with fatty acid metabolism were downregulated. We conclude that alterations in cardiomyocytes after ET-1 treatment go far beyond hypertrophy and represent a useful model for diastolic dysfunction.

Effectiveness of home-based cardiac telerehabilitation based on wearable ECG or heart rate monitoring devices in patients with heart disease: A meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the effectiveness of home-based cardiac telerehabilitation based on wearable electrocardiogram or heart rate monitoring devices in patients with heart disease.

METHODS

We searched eight electronic databases under the guidance of Cochrane Handbook and PRISMA recommendations.

RESULTS

The meta-analysis included data from 14 articles (15 RCTs) representing 1314 participants. A significant improvement in left ventricular ejection fraction [MD = 2.12, 95 % CI (1.21, 3.04), P < 0.001], 6-minute walk distance [MD = 40.00, 95 % CI (21.72, 58.29), P < 0.001] and peak oxygen intake [MD = 2.24, 95 % CI (1.38, 3.10), P < 0.001] were observed in the home-based cardiac telerehabilitation group. But it had no difference in anxiety [SMD = -0.83, 95 % CI (-1.65, -0.02), P = 0.05] and depression [SMD = -0.59, 95 % CI (-1.26, 0.09), P = 0.09]. Subgroup analyses revealed that interventions of no less than 3 months improved anxiety [SMD = -1.11, 95 % CI (-2.05, -0.18), P = 0.02] and depression [SMD = -1.01, 95 % CI (-1.93, -0.08), P = 0.03].

CONCLUSION

Home-based cardiac telerehabilitation based on wearable electrocardiogram or heart rate monitoring devices has a positive effect on cardiac function. Long-term (≥ 3 months) cardiac rehabilitation might benefit individuals suffering from anxiety or depression.

CMR-based cardiac phenotyping in different forms of heart failure

Heart failure (HF) is a heterogenous disease requiring precise diagnostics and knowledge of pathophysiological processes. Since structural and functional imaging data are scarce we hypothesized that cardiac magnetic resonance (CMR)-based analyses would provide accurate characterization and mechanistic insights into different HF groups comprising preserved (HFpEF), mid-range (HFmrEF) and reduced ejection fraction (HFrEF). 22 HFpEF, 17 HFmrEF and 15 HFrEF patients as well as 19 healthy volunteers were included. CMR image assessment contained left atrial (LA) and left ventricular (LV) volumetric evaluation as well as left atrioventricular coupling index (LACI). Furthermore, CMR feature-tracking included LV and LA strain in terms of reservoir (Es), conduit (Ee) and active boosterpump (Ea) function. CMR-based tissue characterization comprised T1 mapping as well as late-gadolinium enhancement (LGE) analyses. HFpEF patients showed predominant atrial impairment (Es 20.8%vs.25.4%, p = 0.02 and Ee 8.3%vs.13.5%, p = 0.001) and increased LACI compared to healthy controls (14.5%vs.23.3%, p = 0.004). Patients with HFmrEF showed LV enlargement but mostly preserved LA function with a compensatory increase in LA boosterpump (LA Ea: 15.0%, p = 0.049). In HFrEF LA and LV functional impairment was documented (Es: 14.2%, Ee: 5.4% p < 0.001 respectively; Ea: 8.8%, p = 0.02). This was paralleled by non-invasively assessed progressive fibrosis (T1 mapping and LGE; HFrEF > HFmrEF > HFpEF). CMR-imaging reveals insights into HF phenotypes with mainly atrial affection in HFpEF, ventricular affection with atrial compensation in HFmrEF and global impairment in HFrEF paralleled by progressive LV fibrosis. These data suggest a necessity for a personalized HF management based on imaging findings for future optimized patient management.

Left Atrial Roof Enlargement Is a Distinct Feature of Heart Failure With Preserved Ejection Fraction

BACKGROUND

It remains unknown to what extent intrinsic atrial cardiomyopathy or left ventricular diastolic dysfunction drive atrial remodeling and functional failure in heart failure with preserved ejection fraction (HFpEF). Computational 3-dimensional (3D) models fitted to cardiovascular magnetic resonance allow state-of-the-art anatomic and functional assessment, and we hypothesized to identify a phenotype linked to HFpEF.

METHODS

Patients with exertional dyspnea and diastolic dysfunction on echocardiography (E/e', >8) were prospectively recruited and classified as HFpEF or noncardiac dyspnea based on right heart catheterization. All patients underwent rest and exercise-stress right heart catheterization and cardiovascular magnetic resonance. Computational 3D anatomic left atrial (LA) models were generated based on short-axis cine sequences. A fully automated pipeline was developed to segment cardiovascular magnetic resonance images and build 3D statistical models of LA shape and find the 3D patterns discriminant between HFpEF and noncardiac dyspnea. In addition, atrial morphology and function were quantified by conventional volumetric analyses and deformation imaging. A clinical follow-up was conducted after 24 months for the evaluation of cardiovascular hospitalization.

RESULTS

Beyond atrial size, the 3D LA models revealed roof dilation as the main feature found in masked HFpEF (diagnosed during exercise-stress only) preceding a pattern shift to overall atrial size in overt HFpEF (diagnosed at rest). Characteristics of the 3D model were integrated into the LA HFpEF shape score, a biomarker to characterize the gradual remodeling between noncardiac dyspnea and HFpEF. The LA HFpEF shape score was able to discriminate HFpEF (n=34) to noncardiac dyspnea (n=34; area under the curve, 0.81) and was associated with a risk for atrial fibrillation occurrence (hazard ratio, 1.02 [95% CI, 1.01-1.04]; P=0.003), as well as cardiovascular hospitalization (hazard ratio, 1.02 [95% CI, 1.00-1.04]; P=0.043).

CONCLUSIONS

LA roof dilation is an early remodeling pattern in masked HFpEF advancing to overall LA enlargement in overt HFpEF. These distinct features predict the occurrence of atrial fibrillation and cardiovascular hospitalization.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03260621.

Right Ventricular Pressure Waveform Analysis-Clinical Relevance and Future Directions

Continuous measurement of pressure in the right atrium and pulmonary artery has commonly been used to monitor right ventricular function in critically ill and surgical patients. This approach is largely based upon the assumption that right atrial and pulmonary arterial pressures provide accurate surrogates for diastolic filling and peak right ventricular pressures, respectively. However, due to both technical and physiologic factors, this assumption is not always true. Accordingly, recent studies have begun to emphasize the potential clinical value of also measuring right ventricular pressure at the bedside. This has highlighted both past and emerging research demonstrating the utility of analyzing not only the amplitude of right ventricular pressure but also the shape of the pressure waveform. This brief review summarizes data demonstrating that combining conventional measurements of right ventricular pressure with variables derived from waveform shape allows for more comprehensive and ideally continuous bedside assessment of right ventricular function, particularly when combined with stroke volume measurement or 3D echocardiography, and discusses the potential use of right ventricular pressure analysis in computational models for evaluating cardiac function.

Relationship between serum uric acid levels and uric acid lowering therapy with the prognosis of patients with heart failure with preserved ejection fraction: a meta-analysis

Aims

This meta-analysis aimed to explore the association between serum uric acid levels and the efficacy of uric acid-lowering therapies on clinical outcomes among patients with heart failure with preserved ejection fraction (HFpEF).

Methods

A comprehensive literature search was conducted through October 21, 2023, across PubMed, Embase, Cochrane Library, and Web of Science databases. The pooled effect sizes were estimated and presented with their respective 95% confidence intervals (CI). Subgroup analyses were conducted based on various factors, including sample size (<1,000 vs. ≥1,000), follow-up duration (<2 years vs. ≥2 years), study quality (assessed by a score of <7 vs. ≥7), ethnicity (Non-Asian vs. Asian), study design (prospective vs. retrospective), type of heart failure (HF) (acute vs. chronic), presence of hyperuricemia (yes or no), left ventricular ejection fraction (LVEF) thresholds (≥45% vs. ≥50%), and the type of uric acid-lowering therapy (traditional vs. novel).

Results

The analysis included a total of 12 studies. Elevated serum uric acid levels were significantly linked to an increased risk of all-cause mortality [relative risk (RR): 1.21, 95% CI: 1.06-1.37, P = 0.004] and cardiovascular (CV) mortality (RR: 1.71, 95% CI: 1.42-2.04, P < 0.001) in HFpEF patients. Subgroup analyses confirmed this association, particularly in non-Asian populations, those with chronic HFpEF, and studies with a follow-up duration of two years or more. Additionally, higher uric acid levels were associated with an increased risk of HF-related hospitalization [hazard ratio (HR): 1.61, 95% CI: 1.12-2.34, P = 0.011]. Regarding treatment, uric acid-lowering therapy did not show a significant effect on reducing mortality in HFpEF patients. However, it was associated with a decreased risk of hospitalization due to HF (RR: 0.85, 95% CI: 0.79-0.91, P < 0.001).

Conclusion

The findings of this study highlight the prognostic significance of serum uric acid levels in HFpEF and suggest that uric acid-lowering therapy may be beneficial in reducing the incidence of HF hospitalizations. Further research is warranted to elucidate the mechanisms by which uric acid-lowering therapy confers its potential benefits.

The impact of atrial fibrillation on clinical outcomes in heart failure with mid-range and preserved ejection fraction patients

BACKGROUND

The combined effect of left ventricular ejection fraction (LVEF) and atrial fibrillation (AF) on clinical outcomes in heart failure (HF) remains complex.

OBJECTIVE

In this post hoc analysis of the TOPCAT trial, we aimed to evaluate the impact of AF on clinical outcomes in patients with HF stratified by LVEF range.

METHODS

A total of 3442 patients were included, stratified into 3 groups according to LVEF range-HF with mid-range ejection fraction (HFmrEF), LVEF of 45%-50% (n = 823); HF with preserved ejection fraction (HFpEF), LVEF of 51%-60% (n = 1682); and HF with normal ejection fraction (HFnEF), LVEF >60% (n = 937)-and subdivided according to the presence of AF at enrollment. Cox regression analysis was used to define independent associations between AF and clinical outcomes.

RESULTS

AF was prevalent in 38.6% in HFmrEF, 34.6% in HFpEF, and 33.7% in HFnEF (P = .07). AF was associated with worse primary outcome in each subgroup and with HF hospitalizations and worse cardiovascular mortality in HFpEF and HFnEF. The hazard ratio for the primary outcome in those with AF compared with sinus rhythm (SR) was 1.11 (1.01-1.22; P = .03) in HFmrEF, 1.20 (1.11-1.29; P < .001) in HFpEF, and 1.16 (1.05-1.28; P = .004) in HFnEF. When LVEF was treated as a continuous variable, there was a linear negative association between LVEF and the effect of AF vs SR for the primary end point and HF hospitalizations and a linear positive association for cardiovascular mortality.

CONCLUSION

Compared with SR, AF was independently associated with worse outcomes across all LVEF ranges.

Mechanisms maintaining right ventricular contractility-to-pulmonary arterial elastance ratio in VA ECMO: a retrospective animal data analysis of RV-PA coupling

BACKGROUND

To optimize right ventricular-pulmonary coupling during veno-arterial (VA) ECMO weaning, inotropes, vasopressors and/or vasodilators are used to change right ventricular (RV) function (contractility) and pulmonary artery (PA) elastance (afterload). RV-PA coupling is the ratio between right ventricular contractility and pulmonary vascular elastance and as such, is a measure of optimized crosstalk between ventricle and vasculature. Little is known about the physiology of RV-PA coupling during VA ECMO. This study describes adaptive mechanisms for maintaining RV-PA coupling resulting from changing pre- and afterload conditions in VA ECMO.

METHODS

In 13 pigs, extracorporeal flow was reduced from 4 to 1 L/min at baseline and increased afterload (pulmonary embolism and hypoxic vasoconstriction). Pressure and flow signals estimated right ventricular end-systolic elastance and pulmonary arterial elastance. Linear mixed-effect models estimated the association between conditions and elastance.

RESULTS

At no extracorporeal flow, end-systolic elastance increased from 0.83 [0.66 to 1.00] mmHg/mL at baseline by 0.44 [0.29 to 0.59] mmHg/mL with pulmonary embolism and by 1.36 [1.21 to 1.51] mmHg/mL with hypoxic pulmonary vasoconstriction (p < 0.001). Pulmonary arterial elastance increased from 0.39 [0.30 to 0.49] mmHg/mL at baseline by 0.36 [0.27 to 0.44] mmHg/mL with pulmonary embolism and by 0.75 [0.67 to 0.84] mmHg/mL with hypoxic pulmonary vasoconstriction (p < 0.001). Coupling remained unchanged (2.1 [1.8 to 2.3] mmHg/mL at baseline; - 0.1 [- 0.3 to 0.1] mmHg/mL increase with pulmonary embolism; - 0.2 [- 0.4 to 0.0] mmHg/mL with hypoxic pulmonary vasoconstriction, p > 0.05). Extracorporeal flow did not change coupling (0.0 [- 0.0 to 0.1] per change of 1 L/min, p > 0.05). End-diastolic volume increased with decreasing extracorporeal flow (7.2 [6.6 to 7.8] ml change per 1 L/min, p < 0.001).

CONCLUSIONS

The right ventricle dilates with increased preload and increases its contractility in response to afterload changes to maintain ventricular-arterial coupling during VA extracorporeal membrane oxygenation.

Rationale and design of the PACIFIC-PRESERVED (PhenomApping, ClassIFication and Innovation for Cardiac dysfunction in patients with heart failure and PRESERVED left ventricular ejection fraction) study

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome that is poorly defined, reflecting an incomplete understanding of its pathophysiology.

AIM

To redefine the phenotypic spectrum of HFpEF.

METHODS

The PACIFIC-PRESERVED study is a prospective multicentre cohort study designed to perform multidimensional deep phenotyping of patients diagnosed with HFpEF (left ventricular ejection fraction≥50%), patients with heart failure with reduced ejection fraction (left ventricular ejection fraction≤40%) and subjects without overt heart failure (3:2:1 ratio). The study proposes prospective investigations in patients during a 1-day hospital stay: physical examination; electrocardiogram; performance-based tests; blood samples; cardiac magnetic resonance imaging; transthoracic echocardiography (rest and low-level exercise); myocardial shear wave elastography; chest computed tomography; and non-invasive measurement of arterial stiffness. Dyspnoea, depression, general health and quality of life will be assessed by dedicated questionnaires. A biobank will be established. After the hospital stay, patients are asked to wear a connected garment (with digital sensors) to collect electrocardiography, pulmonary and activity variables in real-life conditions (for up to 14 days). Data will be centralized for machine-learning-based analyses, with the aim of reclassifying HFpEF into more distinct subgroups, improving understanding of the disease mechanisms and identifying new biological pathways and molecular targets. The study will also serve as a platform to enable the development of innovative technologies and strategies for the diagnosis and stratification of patients with HFpEF.

CONCLUSIONS

PACIFIC-PRESERVED is a prospective multicentre phenomapping study, using novel analytical techniques, which will provide a unique data resource to better define HFpEF and identify new clinically meaningful subgroups of patients.

Sex-specific cardiac magnetic resonance pulmonary capillary wedge pressure

Aims

Heart failure (HF) with preserved ejection fraction disproportionately affects women. There are no validated sex-specific tools for HF diagnosis despite widely reported differences in cardiac structure. This study investigates whether sex, as assigned at birth, influences cardiac magnetic resonance (CMR) assessment of left ventricular filling pressure (LVFP), a hallmark of HF agnostic to ejection fraction.

Methods and results

A derivation cohort of patients with suspected pulmonary hypertension and HF from the Sheffield centre underwent invasive right heart catheterization and CMR within 24 h of each other. A sex-specific CMR model to estimate LVFP, measured as pulmonary capillary wedge pressure (PCWP), was developed using multivariable regression. A validation cohort of patients with confirmed HF from the Leeds centre was used to evaluate for the primary endpoints of HF hospitalization and major adverse cardiovascular events (MACEs). Comparison between generic and sex-specific CMR-derived PCWP was undertaken. A total of 835 (60% female) and 454 (36% female) patients were recruited into the derivation and validation cohorts respectively. A sex-specific model incorporating left atrial volume and left ventricular mass was created. The generic CMR PCWP showed significant differences between males and females (14.7 ± 4 vs. 13 ± 3.0 mmHg, P > 0.001), not present with the sex-specific CMR PCWP (14.1 ± 3 vs. 13.8 mmHg, P = 0.3). The sex-specific, but not the generic, CMR PCWP was associated with HF hospitalization (hazard ratio 3.9, P = 0.0002) and MACE (hazard ratio 2.5, P = 0.001) over a mean follow-up period of 2.4 ± 1.2 years.

Conclusion

Accounting for sex improves precision and prognostic performance of CMR biomarkers for HF.

Differential sex-related effect of left ventricular ejection fraction trajectory on the risk of mortality and heart failure readmission following hospitalization for acute heart failure: A longitudinal study

AIMS

There is limited information on the sex-specific longitudinal changes of left ventricular ejection fraction (LVEF) after an acute heart failure (AHF) hospitalization. We aimed to investigate whether LVEF trajectories over time and their impact on mortality and AHF readmission rates differ between men and women.

METHODS AND RESULTS

We conducted a retrospective sex-specific analysis of longitudinal LVEF measurements (n = 9581) in 3383 patients with an index hospitalization for AHF in a single tertiary-level hospital. Statistical techniques suited for longitudinal data analysis were used. The mean age of the sample was 73.8 ± 11.2 years, and 47.9% were women. The mean LVEF was 49.4 ± 15.3%. At a median follow-up of 2.58 years (interquartile range 0.77-5.62), we registered 2197 deaths (64.9%) and 2597 AHF readmissions in 1302 (38.5%) patients. The longitudinal analysis showed that women had consistently higher LVEF values throughout the follow-up with both trajectories characterized by an early peak-approximately at 1 year-followed by decreasing values in men but a plateau in women. Multivariate between-sex comparisons across LVEF categories revealed that women had lower rates of AHF readmissions when LVEF ≤40%. On the contrary, women displayed an excess risk of AHF readmissions when LVEF >60%. A trend in the same direction was found for cardiovascular and all-cause mortality.

CONCLUSION

Sex was a significant factor in determining the follow-up trajectory of LVEF and predicting differences in outcomes after an AHF admission. The findings suggest that women have a higher risk of AHF readmissions at higher LVEF values, while men have a higher risk at lower LVEF values. For all-cause and cardiovascular mortality, the same direction of the association was inferred but they were not significant.

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.

Trajectories of functional and structural myocardial parameters in post-COVID-19 syndrome-insights from mid-term follow-up by cardiovascular magnetic resonance

Introduction

Myocardial tissue alterations in patients with post-Coronavirus disease 2019 syndrome (PCS) are often subtle and mild. Reports vary in the prevalence of non-ischemic and ischemic injuries as well as the extent of ongoing myocardial inflammation. The exact relevance of these myocardial alterations is not fully understood. This study aimed at describing the trajectories of myocardial alterations in PCS patients by mid-term follow-up with cardiovascular magnetic resonance (CMR).

Methods

This study entails a retrospective analysis of symptomatic PCS patients referred for follow-up CMR between August 2020 and May 2023 due to mildly affected or reduced left or right ventricular function (LV and RV, respectively) and structural myocardial alterations, e.g., focal and diffuse fibrosis, on baseline scans. Follow-up CMR protocol consisted of cine images and full coverage native T1 and T2 mapping. Baseline and follow-up scans were compared using t-tests or Wilcoxon tests. Post-hoc analysis was carried out in a subgroup based on the change of LV stroke volume (SV) between scans.

Results

In total, 43 patients [median age (interquartile range) 46 (37-56) years, 33 women] received follow-ups 347 (167-651) days after initial diagnosis. A decrease in symptoms was recorded on follow-ups (p < 0.03) with 23 patients being asymptomatic at follow-ups [symptomatic at baseline 43/43 (100%) vs. symptomatic at follow-up 21/43 (49%), p < 0.001]. Functional improvement was noted for LV-SV [83.3 (72.7-95.0) vs. 84.0 (77.0-100.3) ml; p = 0.045], global radial [25.3% (23.4%-27.9%) vs. 27.4% (24.4%-33.1%); p < 0.001], and circumferential strains [-16.5% (-17.5% to -15.6%) vs. -17.2% (-19.5% to -16.1%); p < 0.001]. In total, 17 patients had an LV-SV change >10% on follow-up scans (5 with a decrease and 12 with an increase), with LV-SV, RV-SV, and global longitudinal strain being discriminatory variables on baseline scans (p = 0.01, 0.02, and 0.04, respectively). T1- or T2-analysis revealed no changes, remaining within normal limits.

Conclusion

Symptomatic load as well as blood pressures decreased on follow-up. CMR did not detect significant changes in tissue parameters; however, volumetric, specifically LV-SV, and deformation indexes improved during mid-term follow-up.

Profiling the Biomechanical Responses to Workload on the Human Myocyte to Explore the Concept of Myocardial Fatigue and Reversibility: Rationale and Design of the POWER Heart Failure Study

It remains unclear why some patients develop heart failure without evidence of structural damage. One theory relates to impaired myocardial energetics and ventricular-arterial decoupling as the heart works against adverse mechanical load. In this original study, we propose the novel concept of myocardial fatigue to capture this phenomenon and aim to investigate this using human cardiomyocytes subjected to a modern work-loop contractility model that closely mimics in vivo cardiac cycles. This proof-of-concept study (NCT04899635) will use human myocardial tissue samples from patients undergoing cardiac surgery to develop a reproducible protocol to isolate robust calcium-tolerant cardiomyocytes. Thereafter, work-loop contractility experiments will be performed over a range of preload, afterload and cycle frequency as a function of time to elicit any reversible reduction in contractile performance (i.e. fatigue). This will provide novel insight into mechanisms behind heart failure and myocardial recovery and serve as a valuable research platform in translational cardiovascular research.

Impairment of the adrenergic reserve associated with exercise intolerance in a murine model of heart failure with preserved ejection fraction

AIM

Exercise intolerance is the central symptom in patients with heart failure with preserved ejection fraction. In the present study, we investigated the adrenergic reserve both in vivo and in cardiomyocytes of a murine cardiometabolic HFpEF model.

METHODS

12-week-old male C57BL/6J mice were fed regular chow (control) or a high-fat diet and L-NAME (HFpEF) for 15 weeks. At 27 weeks, we performed (stress) echocardiography and exercise testing and measured the adrenergic reserve and its modulation by nitric oxide and reactive oxygen species in left ventricular cardiomyocytes.

RESULTS

HFpEF mice (preserved left ventricular ejection fraction, increased E/e', pulmonary congestion [wet lung weight/TL]) exhibited reduced exercise capacity and a reduction of stroke volume and cardiac output with adrenergic stress. In ventricular cardiomyocytes isolated from HFpEF mice, sarcomere shortening had a higher amplitude and faster relaxation compared to control animals. Increased shortening was caused by a shift of myofilament calcium sensitivity. With addition of isoproterenol, there were no differences in sarcomere function between HFpEF and control mice. This resulted in a reduced inotropic and lusitropic reserve in HFpEF cardiomyocytes. Preincubation with inhibitors of nitric oxide synthases or glutathione partially restored the adrenergic reserve in cardiomyocytes in HFpEF.

CONCLUSION

In this murine HFpEF model, the cardiac output reserve on adrenergic stimulation is impaired. In ventricular cardiomyocytes, we found a congruent loss of the adrenergic inotropic and lusitropic reserve. This was caused by increased contractility and faster relaxation at rest, partially mediated by nitro-oxidative signaling.

Implications of tricuspid regurgitation and right ventricular volume overload in patients with heart failure with preserved ejection fraction

AIMS

The aim of this study was to assess the pathophysiological implications of severe tricuspid regurgitation (TR) in patients with heart failure with preserved ejection fraction (HFpEF) by using tricuspid transcatheter edge-to-edge repair (T-TEER) as a model of right ventricular (RV) volume overload relief.

METHODS AND RESULTS

This prospective interventional single arm trial (NCT04782908) included patients with invasively diagnosed HFpEF. The following parameters were prospectively assessed before and after T-TEER: left ventricular (LV) diastolic properties by invasive pressure-volume loop recordings; biventricular time-volume curves and function as well as septal curvature by cardiac magnetic resonance imaging; strain analyses for timing of septal motion. Overall, 20 patients (median age 78, interquartile range [IQR] 72-83 years, 65% female) were included. T-TEER reduced TR by a median of 2 (of 5) grades (IQR 2-1). T-TEER increased LV stroke volume and LV end-diastolic volume (LVEDV) (p < 0.001), without increasing LV end-diastolic pressure (LVEDP) (p = 0.094), consequently diastolic function improved with a reduction in LVEDP/LVEDV (p = 0.001) and a rightward shift of the end-diastolic pressure-volume relationship. The increase in LVEDV correlated with a decrease in RV end-diastolic volume (p < 0.001) and LV transmural pressure increased (p = 0.028). Secondary to a decrease in early RV filling, improvements in early LV filling were observed, correlating with an alleviation of leftwards bowing of the septum (p < 0.01, respectively).

CONCLUSION

Diastolic LV properties in patients with HFpEF and severe TR are importantly determined by ventricular interaction in the setting of RV volume overload. T-TEER reduces RV volume overload and improves biventricular interaction and physiology.

Noncardiovascular morbidity and mortality across left ventricular ejection fraction categories following hospitalization for heart failure

INTRODUCTION AND OBJECTIVES

Noncardiovascular events represent a significant proportion of the morbidity and mortality burden in patients with heart failure (HF). However, the risk of these events appears to differ by left ventricular ejection fraction (LVEF) status. In this study, we sought to evaluate the risk of noncardiovascular death and recurrent noncardiovascular readmission by LVEF status following an admission for acute HF.

METHODS

We retrospectively assessed a cohort of 4595 patients discharged after acute HF in a multicenter registry. We evaluated LVEF as a continuum, stratified in 4 categories (LVEF ≤ 40%, 41%-49%, 50%-59%, and ≥ 60%). Study endpoints were the risks of noncardiovascular mortality and recurrent noncardiovascular admissions during follow-up.

RESULTS

At a median follow-up of 2.2 [interquartile range, 0.76-4.8] years, we registered 646 noncardiovascular deaths and 4014 noncardiovascular readmissions. After multivariable adjustment including cardiovascular events as a competing event, LVEF status was associated with the risk of noncardiovascular mortality and recurrent noncardiovascular admissions. When compared with patients with LVEF ≤ 40%, those with LVEF 51%-59%, and especially those with LVEF ≥ 60%, were at higher risk of noncardiovascular mortality (HR, 1.31; 95%CI, 1.02-1,68; P=.032; and HR, 1.47; 95%CI, 1.15-1.86; P=.002; respectively), and at higher risk of recurrent noncardiovascular admissions (IRR, 1.17; 95%CI, 1.02-1.35; P=.024; and IRR, 1.26; 95%CI, 1.11-1.45; P=.001; respectively).

CONCLUSIONS

Following an admission for HF, LVEF status was directly associated with the risk of noncardiovascular morbidity and mortality. Patients with HFpEF were at higher risk of noncardiovascular death and total noncardiovascular readmissions, especially those with LVEF ≥ 60%.

Risk of supranormal left ventricular ejection fraction in patients with aortic stenosis

BACKGROUND

Cardiovascular events are increasing in patients with supranormal left ventricular ejection fraction (snLVEF). However, the effect of snLVEF in patients with aortic stenosis (AS) remains unclear, especially in patients with moderate AS.

HYPOTHESIS

This study aimed to evaluate the prognosis of mortality and heart failure (HF) in patients with LVEF ≥ 50% and moderate or severe AS.

METHODS

This retrospective study targeted patients with moderate or severe AS and LVEF > 50%. LVEF of 50%-65% was classified as normal LVEF (nLVEF, nEF group) and >65% as snLVEF (snEF group). AS severity was stratified based on the aortic valve area into moderate (1.0-1.5 cm²) and severe (<1.0 cm²). Primary outcomes included all-cause mortality and HF hospitalization.

RESULTS

A total of 226 participants were included in this study. There were 67 and 65 participants with moderate AS in snEF (m-snEF) and nEF groups (m-nEF), respectively, and 41 and 53 participants with severe AS in the snEF (s-snEF) and nEF groups (s-nEF), respectively. During the observation period (median: 554 days), the primary composite outcome occurred in 108 individuals. Cox hazard analysis revealed no significant differences among the four groups in primary composite outcomes. With respect to HF hospitalization, the adjusted hazard ratios (95% confidence intervals) with m-snEF as the reference were as follows: m-nEF, 0.41 (0.19-0.89); s-nEF, 1.43 (0.76-2.67); and s-snEF, 1.83 (1.00-3.35).

CONCLUSIONS

The risk of HF hospitalization for m-snLVEF was higher than m-nLVEF and not significantly different from s-nLVEF.

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.

Sex Differences in Cardiac and Clinical Phenotypes and Their Relation to Outcomes in Patients with Heart Failure

Biological sex is one of the major factors characterizing the heart failure (HF) patient phenotype. Understanding sex-related differences in HF is crucial to implement personalized care for HF patients with various phenotypes. There are sex differences in left ventricular (LV) remodeling patterns in the HF setting, namely, more likely concentric remodeling and diastolic dysfunction in women and eccentric remodeling and systolic dysfunction in men. Recently supra-normal EF (snLVEF) has been recognized as a risk of worse outcome. This pathology might be more relevant in female patients. The possible mechanism may be through coronary microvascular dysfunction and sympathetic nerve overactivation from the findings of previous studies. Further, estrogen deficit might play a significant role in this pathophysiology. The sex difference in body composition may also be related to the difference in LV remodeling and outcome. Lower implementation in guideline-directed medical therapy (GDMT) in female HFrEF patients might also be one of the factors related to sex differences in relation to outcomes. In this review, we will discuss the sex differences in cardiac and clinical phenotypes and their relation to outcomes in HF patients and further discuss how to provide appropriate treatment strategies for female patients.

Left ventricular ejection fraction: clinical, pathophysiological, and technical limitations

Risk stratification of cardiovascular death and treatment strategies in patients with heart failure (HF), the optimal timing for valve replacement, and the selection of patients for implantable cardioverter defibrillators are based on an echocardiographic calculation of left ventricular ejection fraction (LVEF) in most guidelines. As a marker of systolic function, LVEF has important limitations being affected by loading conditions and cavity geometry, as well as image quality, thus impacting inter- and intra-observer measurement variability. LVEF is a product of shortening of the three components of myocardial fibres: longitudinal, circumferential, and oblique. It is therefore a marker of global ejection performance based on cavity volume changes, rather than directly reflecting myocardial contractile function, hence may be normal even when myofibril's systolic function is impaired. Sub-endocardial longitudinal fibers are the most sensitive layers to ischemia, so when dysfunctional, the circumferential fibers may compensate for it and maintain the overall LVEF. Likewise, in patients with HF, LVEF is used to stratify subgroups, an approach that has prognostic implications but without a direct relationship. HF is a dynamic disease that may worsen or improve over time according to the underlying pathology. Such dynamicity impacts LVEF and its use to guide treatment. The same applies to changes in LVEF following interventional procedures. In this review, we analyze the clinical, pathophysiological, and technical limitations of LVEF across a wide range of cardiovascular pathologies.

Interaction between systemic iron parameters and left ventricular structure and function in the preserved ejection fraction population: a two-sample bidirectional Mendelian randomization study

BACKGROUND

Left ventricular (LV) remodeling and diastolic function in people with heart failure (HF) are correlated with iron status; however, the causality is uncertain. This Mendelian randomization (MR) study investigated the bidirectional causal relationship between systemic iron parameters and LV structure and function in a preserved ejection fraction population.

METHODS

Transferrin saturation (TSAT), total iron binding capacity (TIBC), and serum iron and ferritin levels were extracted as instrumental variables for iron parameters from meta-analyses of public genome-wide association studies. Individuals without myocardial infarction history, HF, or LV ejection fraction (LVEF) < 50% (n = 16,923) in the UK Biobank Cardiovascular Magnetic Resonance Imaging Study constituted the outcome dataset. The dataset included LV end-diastolic volume, LV end-systolic volume, LV mass (LVM), and LVM-to-end-diastolic volume ratio (LVMVR). We used a two-sample bidirectional MR study with inverse variance weighting (IVW) as the primary analysis method and estimation methods using different algorithms to improve the robustness of the results.

RESULTS

In the IVW analysis, one standard deviation (SD) increased in TSAT significantly correlated with decreased LVMVR (β = -0.1365; 95% confidence interval [CI]: -0.2092 to -0.0638; P = 0.0002) after Bonferroni adjustment. Conversely, no significant relationships were observed between other iron and LV parameters. After Bonferroni correction, reverse MR analysis showed that one SD increase in LVEF significantly correlated with decreased TSAT (β = -0.0699; 95% CI: -0.1087 to -0.0311; P = 0.0004). No heterogeneity or pleiotropic effects evidence was observed in the analysis.

CONCLUSIONS

We demonstrated a causal relationship between TSAT and LV remodeling and function in a preserved ejection fraction population.

Effect of paced heart rate on quality of life and natriuretic peptides for stage B or C heart failure with preserved ejection fraction: A secondary analysis of the myPACE trial

AIM

Emerging evidence suggests a beneficial effect of higher heart rates in some patients with heart failure with preserved ejection fraction (HFpEF). This study aimed to evaluate the impact of higher backup pacing rates in HFpEF patients with preexisting pacemaker systems that limit pacemaker-mediated dyssynchrony across left ventricular (LV) volumes and LV ejection fraction (LVEF).

METHODS AND RESULTS

This is a post-hoc analysis of the myPACE clinical trial that evaluated the effects of personalized accelerated pacing setting (myPACE) versus standard of care on changes in Minnesota Living with Heart Failure Questionnaire (MLHFQ) score, N-terminal pro-brain natriuretic peptide (NT-proBNP), pacemaker-detected activity levels, and atrial fibrillation (AF) burden in patients with HFpEF with preexisting pacemakers. Between-treatment comparisons were performed using linear regression models adjusting for the baseline value of the exposure (ANCOVA design). This study included 93 patients with pre-trial transthoracic echocardiograms available (usual care n = 49; myPACE n = 44). NT-proBNP levels and MLHFQ scores improved in a higher magnitude in the myPACE group at lower indexed LV end-diastolic volumes (iLVEDV) (NT-proBNP-iLVEDV interaction p = 0.006; MLHFQ-iLVEDV interaction p = 0.068). In addition, personalized accelerated pacing led to improved changes in activity levels and NT-proBNP, especially at higher LVEF (activity levels-LVEF interaction p = 0.009; NT-proBNP-LVEF interaction p = 0.058). No evidence of heterogeneity was found across LV volumes or LVEF for pacemaker-detected AF burden.

CONCLUSIONS

In the post-hoc analysis of the myPACE trial, we observed that the benefits of a personalized accelerated backup pacing on MLHFQ score, NT-proBNP, and pacemaker-detected activity levels appear to be more pronounced in patients with smaller iLVEDV and higher LVEF.

Semaglutide in Patients With Obesity and Heart Failure Across Mildly Reduced or Preserved Ejection Fraction

BACKGROUND

Many therapies for heart failure (HF) have shown differential impact across the spectrum of left ventricular ejection fraction (LVEF).

OBJECTIVES

In this prespecified analysis, the authors assessed the effects of semaglutide across the baseline LVEF strata in patients with the obesity phenotype of HF with preserved ejection fraction (HFpEF) in the STEP-HFpEF (Semaglutide Treatment Effect in People with obesity and HFpEF) trial.

METHODS

STEP-HFpEF randomized 529 patients (263 semaglutide; 266 placebo). For this prespecified analysis, patients were categorized into 3 groups based on LVEF: 45% to 49% (n = 85), 50% to 59% (n = 215), and ≥60% (n = 229).

RESULTS

At 52 weeks, semaglutide improved the dual primary endpoints of Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (estimated treatment difference: EF [ejection fraction] 45%-49%: 5.0 points [95% CI: -2.7 to 12.8 points], EF 50%-59%: 9.8 points [95% CI: 5.0 to 14.6 points], and EF ≥60%: 7.4 points [95% CI: 2.8 to 12.0 points]; P interaction = 0.56) and body weight (EF: 45%-49%: -7.6 [95% CI: -10.7 to -4.4], EF 50%-59%: -10.6 [95% CI: -12.6 to -8.6] and EF ≥60%: -11.9 [95% CI: -13.8 to -9.9]; P interaction = 0.08), to a similar extent across LVEF categories. Likewise, LVEF did not influence the benefit of semaglutide on confirmatory secondary endpoints: 6-minute walk distance (P interaction = 0.19), hierarchal composite endpoint (P interaction = 0.43), and high-sensitivity C-reactive protein (P interaction = 0.26); or exploratory endpoint of N-terminal pro-brain natriuretic peptide (P interaction = 0.96). Semaglutide was well-tolerated across LVEF categories.

CONCLUSIONS

In patients with HFpEF and obesity, semaglutide 2.4 mg improved symptoms, physical limitations, and exercise function, and reduced inflammation and body weight to a similar extent across LVEF categories. These data support treatment with semaglutide in patients with the obesity phenotype of HFpEF regardless of LVEF. (Research Study to Investigate How Well Semaglutide Works in People Living With Heart Failure and Obesity [STEP-HFpEF]; NCT04788511).

Supra-Normal Left Ventricular Function

Heart failure (HF) is often categorized by left ventricular (LV) ejection fraction (LVEF). A new category of HF characterized by supra-normal LVEF (>65%), named HF with supra-normal ejection fraction (HFsnEF), has been recently proposed. Some studies reported that patients with supra-normal LVEF might have an increased risk of long-term major adverse cardiovascular events and U-shaped mortality patterns. Currently, the prognosis of HFsnEF is not well established but seems to be associated with an increased risk of long-term major adverse cardiovascular events. It has been reported that HFsnEF is more prevalent in women and is associated with higher prevalence of nonischemic HF, higher blood urea nitrogen plasma levels, lower levels of natriuretic peptides, and to be less likely treated with β blockers. The pathophysiology of HFsnEF would be associated with microvascular dysfunction because of microvascular inflammation or reduced coronary flow reserve, and low stroke volume index with smaller cardiac chamber dimensions and concentric LV geometry. In this study, we systematically reviewed published data on patients with s supra-normal LV function and reported its definition, proposed pathophysiology, phenotypes, diagnostic strategy, and prognosis.

[Heart Failure With Low and Preserved Left Ventricular Ejection Fraction - are These Two Different Independent Diseases or One Disease, but at Different Stages of its Progression? How Does This Affect the Choice of Therapy and Its Effectiveness?]

The article discusses the question of whether it is possible to conclude that any heart failure (HF), throughout the entire range of left ventricular ejection fractions (LVEF), is a single holistic disease, based on the "external" similarity of treatments for reduced (HFrEF) and preserved (HFpEF) LVEF, and that positioning HFpEF and HFrEF as separate independent diseases is not valid.

Understanding Exercise Capacity: From Elite Athlete to HFpEF

Exercise capacity is a spectrum that reflects an individual's functional capacity and the dynamic nature of cardiac remodelling along with respiratory and skeletal muscle systems. The relationship of increasing physical activity, increased cardiac mass and volumes, and improved cardiorespiratory fitness (CRF) is well established in the endurance athlete. However, less emphasis has been placed on the other end of the spectrum, which includes individuals with a more sedentary lifestyle and small hearts who are at increased risk of functional disability and poor clinical outcomes. Reduced CRF is an independent predictor of all-cause mortality and cardiovascular events determined by multiple inter-related exogenous and endogenous factors. In this review, we explore the relationship of physical activity, cardiac remodelling, and CRF across the exercise spectrum, emphasising the critical role of cardiac size in determining exercise capacity. In contrast to the large compliant left ventricle of the endurance athlete, an individual with a lifetime of physical inactivity is likely to have a small, stiff heart with reduced cardiac reserve. We propose that this might contribute to the development of heart failure with preserved ejection fraction in certain individuals, and is key to understanding the link between low CRF and increased risk of heart failure.

Diastolic exercise stress testing in heart failure with preserved ejection fraction: The DEST-HF study

AIMS

Pulmonary capillary wedge pressure (PAWP) ≥25 mmHg during bicycle ergometry is recommended to uncover occult heart failure with preserved ejection fraction. We hypothesized that PAWP increase would differ in available diastolic stress tests and that the margin of PAWP ≥25 mmHg would only be reliably achieved through ergometry.

METHODS AND RESULTS

We conducted a prospective, single-arm study in patients with an intermediate risk for heart failure with preserved ejection fraction according to the ESC HFA-PEFF score. A total of 19 patients underwent four stress test modalities in randomized order: leg raise, fluid challenge, handgrip, and bicycle ergometry. The primary outcome was the difference (Δ) between resting and exercise PAWP in each modality. Secondary outcomes were differences (Δ) in mean pulmonary artery pressure (mPAP), cardiac output (CO), as well as the ratios between mPAP and PAWP to CO. Compared to resting values, passive leg raise (Δ7.7 ± 8.0 mmHg, p = 0.030), fluid challenge (Δ9.2 ± 6.4 mmHg, p = 0.003), dynamic handgrip (Δ9.6 ± 7.5 mmHg, p = 0.002), and bicycle ergometry (Δ22.3 ± 5.0 mmHg, p < 0.001) uncovered increased PAWP during exercise. Amongst these, bicycle ergometry also demonstrated the highest ΔmPAP (27.2 ± 7.1 mmHg, p < 0.001), ΔCO (3.3 ± 2.6 L/min, p < 0.001), ΔmPAP/CO ratio (2.3 ± 2.0 mmHg/L/min, p < 0.001), and ΔPAWP/CO ratio (2.2 ± 1.4 mmHg/L/min, p < 0.001) compared to other modalities. PAWP ≥25 mmHg was only reliably achieved in bicycle ergometry (31.1 ± 3.9 mmHg). In all other modalities only 10.5% of patients achieved PAWP ≥25 mmHg (handgrip 18.4 ± 6.6 mmHg, fluid 18.1 ± 5.6 mmHg, leg raise 16.5 ± 7.0 mmHg).

CONCLUSIONS

We demonstrate that bicycle ergometry exhibits a distinct haemodynamic response with higher increase of PAWP compared to other modalities. This finding needs to be considered for valid detection of exercise PAWP ≥25 mmHg when non-bicycle tests remain inconclusive.

Modulation of Pulsatile Left Ventricular Afterload by Renal Denervation in Heart Failure With Preserved Ejection Fraction

BACKGROUND

Arterial stiffening contributes to hemodynamic derangements in heart failure with preserved ejection fraction (HFpEF). We sought to investigate the impact of renal denervation on pulsatile left ventricular loading in patients with HFpEF and hypertensive patients without heart failure (control).

METHODS

Patients underwent renal denervation for treatment of hypertension and were followed up at 3 months at a single center. A validated computer model of the arterial tree, noninvasive aortic flow curves, left ventricular volumes, and E/e' as inputs were used to determine key parameters of left ventricular vascular load.

RESULTS

In comparison to controls (n=30), patients with HFpEF (n=30) demonstrated lower total arterial compliance (mean difference, -0.41 [95% CI, -0.72 to -0.10] mL/mm Hg), higher impedance of the proximal aorta (Zc: 0.02; 0.01 to 0.04 mHg·s/mL), premature wave reflections (shorter backward wave transit time normalized to ejection time: -3.5; -6.5% to -0.5%), and higher wave reflection magnitude (reflection coefficient: 7.3; 2.8% to 11.9%). Overall, daytime systolic (-9.2; -12.2 to -6.2 mm Hg) and diastolic blood pressures (-5.9; -7.6 to -4.1 mm Hg) as well as blood pressure variability (-2.0; -3.0 to -0.9 mm Hg) decreased after renal denervation. In patients with HFpEF, total arterial compliance (0.42; 0.17 to 0.67 mL/mm Hg) and backward transit time normalized to ejection time (1.7; 0.4% to 3.0%) increased; Zc (-0.01; -0.02 to -0.01 mm Hg·s/mL) and reflection coefficient (-2.6; -5.0% to -0.3%) decreased after renal denervation. This was accompanied by a symptomatic improvement in patients with HFpEF.

CONCLUSION

HFpEF is characterized by heightened aortic stiffness and unfavorable pulsatile left ventricular load. These abnormalities are partly normalized after renal denervation.

Assessment of Microvascular Disease in Heart and Brain by MRI: Application in Heart Failure with Preserved Ejection Fraction and Cerebral Small Vessel Disease

The objective of this review is to investigate the commonalities of microvascular (small vessel) disease in heart failure with preserved ejection fraction (HFpEF) and cerebral small vessel disease (CSVD). Furthermore, the review aims to evaluate the current magnetic resonance imaging (MRI) diagnostic techniques for both conditions. By comparing the two conditions, this review seeks to identify potential opportunities to improve the understanding of both HFpEF and CSVD.

Novel insights into diminished cardiac reserve in non-obstructive hypertrophic cardiomyopathy from four-dimensional flow cardiac magnetic resonance component analysis

AIMS

Hypertrophic cardiomyopathy (HCM) is characterized by hypercontractility and diastolic dysfunction, which alter blood flow haemodynamics and are linked with increased risk of adverse clinical events. Four-dimensional flow cardiac magnetic resonance (4D-flow CMR) enables comprehensive characterization of ventricular blood flow patterns. We characterized flow component changes in non-obstructive HCM and assessed their relationship with phenotypic severity and sudden cardiac death (SCD) risk.

METHODS AND RESULTS

Fifty-one participants (37 non-obstructive HCM and 14 matched controls) underwent 4D-flow CMR. Left-ventricular (LV) end-diastolic volume was separated into four components: direct flow (blood transiting the ventricle within one cycle), retained inflow (blood entering the ventricle and retained for one cycle), delayed ejection flow (retained ventricular blood ejected during systole), and residual volume (ventricular blood retained for >two cycles). Flow component distribution and component end-diastolic kinetic energy/mL were estimated. HCM patients demonstrated greater direct flow proportions compared with controls (47.9 ± 9% vs. 39.4 ± 6%, P = 0.002), with reduction in other components. Direct flow proportions correlated with LV mass index (r = 0.40, P = 0.004), end-diastolic volume index (r = -0.40, P = 0.017), and SCD risk (r = 0.34, P = 0.039). In contrast to controls, in HCM, stroke volume decreased with increasing direct flow proportions, indicating diminished volumetric reserve. There was no difference in component end-diastolic kinetic energy/mL.

CONCLUSION

Non-obstructive HCM possesses a distinctive flow component distribution pattern characterised by greater direct flow proportions, and direct flow-stroke volume uncoupling indicative of diminished cardiac reserve. The correlation of direct flow proportion with phenotypic severity and SCD risk highlight its potential as a novel and sensitive haemodynamic measure of cardiovascular risk in HCM.

Association between the atrial tachyarrhythmia recurrence period and long-term major adverse clinical events following catheter ablation for atrial fibrillation

Background

We previously demonstrated the clinical events in patients who underwent catheter ablation (CA) for atrial fibrillation (AF). Data on the association between the period of atrial tachyarrhythmia (ATA) recurrence after CA and long-term major adverse clinical events (MACE) remain unclear. In this study, we evaluated this issue in patients with systolic impairment (left ventricular ejection fraction < 50%) and heart failure with preserved ejection fraction (HFpEF).

Methods

We retrospectively collected data from 81 patients with systolic impairment and 83 patients with HFpEF who underwent CA for AF at our institution (median follow-up: 4.9 [3.6, 6.6] years). In each group, we compared the cumulative incidence of long-term MACE (since 1 year after CA) between patients with and without ATA recurrence at three follow-up periods (3, 6 months, and 1 year after index CA). We evaluated the period of recurrence, which was the most beneficial predictor of MACE among the periods.

Results

In the systolic impairment group, the cumulative long-term MACE incidence was significantly higher in patients with ATA recurrence than in those without it within 6 months and 1 year (P = 0.04 and P = 0.01, respectively). Recurrence within 1 year showed the highest feasibility for predicting long-term MACE (area under the curve with 95% confidence interval [CI]:0.73 [0.61-0.84]). However, there was no difference in the incidence of MACE between patients with and without recurrence in a group with HFpEF in each period.

Conclusion

ATA recurrence within 1 year could predict long-term MACE in patients with systolic impairment, but not in patients with HFpEF.

The First Dedicated Comprehensive Heart Failure Program in the United States: The Division of Circulatory Physiology at Columbia Presbyterian (1992-2004)

The first dedicated multidisciplinary heart failure program in the United States was founded as the Division of Circulatory Physiology at the Columbia University College of Physicians & Surgeons in 1992. The Division was administratively and financially independent of the Division of Cardiology and grew to 24 faculty members at its peak. Its administrative innovations included (1) a comprehensive full-integrated service line, with 2 differentiated clinical teams, one devoted to drug therapy and the other to heart transplantation and ventricular assist devices; (2) a nurse specialist/physician assistant-led clinical service; and (3) a financial structure independent of (and not supported by) other cardiovascular medical or surgical services. The division had 3 overarching missions: (1) to promote a unique career development path for each faculty member to be linked to recognition in a specific area of heart failure expertise; (2) to change the trajectory and enhance the richness of intellectual discourse in the discipline of heart failure, so as to foster an understanding of fundamental mechanisms and to develop new therapeutics; and (3) to provide optimal medical care to patients and to promote the ability of other physicians to provide optimal care. The major research achievements of the division included (1) the development of beta-blockers for heart failure, from initial hemodynamic assessments to proof-of-concept studies to large-scale international trials; (2) the development and definitive assessment of flosequinan, amlodipine, and endothelin antagonists; (3) initial clinical trials and concerns with nesiritide; (4) large-scale trials evaluating dosing of angiotensin converting-enzyme inhibitors and the efficacy and safety of neprilysin inhibition; (5) identification of key mechanisms in heart failure, including neurohormonal activation, microcirculatory endothelial dysfunction, deficiencies in peripheral vasodilator pathways, noncardiac factors in driving dyspnea, and the first identification of subphenotypes of heart failure and a preserved ejection fraction; (6) the development of a volumetric approach to the assessment of myocardial shortening; (7) conceptualization and early studies of cardiac contractility modulation as a treatment for heart failure; (8) novel approaches to the identification of cardiac allograft rejection and new therapeutics to prevent allograft vasculopathy; and (9) demonstration of the effect of left ventricular assist devices to induce reverse remodeling, and the first randomized trial showing a survival benefit with ventricular assist devices. Above all, the division served as an exceptional incubator for a generation of leaders in the field of heart failure.

Sex-Specific Impairment of Cardiac Functional Reserve in HFpEF: Insights From the HFpEF Stress Trial

Background

Heart failure with preserved ejection fraction (HFpEF) has been observed to have a twice as high prevalence in women compared to men with similar predisposing risk factors between both sexes.

Objectives

This study aimed to identify sex-specific pathophysiological features in HFpEF using rest and exercise stress right heart catheterization (RHC), echocardiography and cardiovascular magnetic resonance imaging (CMR).

Methods

Seventy-five patients with exertional dyspnea, preserved ejection fraction (EF) (≥50%), and signs of diastolic dysfunction on echocardiography were prospectively recruited in the HFpEF Stress Trial. Patients underwent RHC, echocardiography and CMR at rest and during exercise stress. Patients were diagnosed with HFpEF and noncardiac dyspnea according to RHC measurements.

Results

After exclusion, the final study cohort comprised 68 patients (females n = 44, males n = 24) with a mean age of 66.9 ± 9.7 years. Compared to men, women with HFpEF revealed lower right ventricular stroke volumes during exercise stress (females 38.1 vs males 50.4 mL/m2 BSA; P = 0.011). This was accompanied by a decreasing left atrial EF in women but not men comparing resting to exercise conditions (females -2.7% vs males 2.5%, P = 0.020) and impaired left ventricular filling (females 35.5 vs males 44.2 mL/m2 BSA, P = 0.017) in women with HFpEF during exercise stress. These sex-specific differences were not present in noncardiac dyspnea.

Conclusions

Women with HFpEF demonstrate sex-specific functional alterations of right ventricular, left atrial, and left ventricular function during exercise stress. This unique pathophysiology represents a sex-specific diagnostic target, which may allow early identification of women with HFpEF for future individualized therapeutic approaches.

Heart Failure With Preserved Ejection Fraction: JACC Scientific Statement

The incidence and prevalence of heart failure with preserved ejection fraction (HFpEF) continue to rise in tandem with the increasing age and burdens of obesity, sedentariness, and cardiometabolic disorders. Despite recent advances in the understanding of its pathophysiological effects on the heart, lungs, and extracardiac tissues, and introduction of new, easily implemented approaches to diagnosis, HFpEF remains under-recognized in everyday practice. This under-recognition presents an even greater concern given the recent identification of highly effective pharmacologic-based and lifestyle-based treatments that can improve clinical status and reduce morbidity and mortality. HFpEF is a heterogenous syndrome and recent studies have suggested an important role for careful, pathophysiological-based phenotyping to improve patient characterization and to better individualize treatment. In this JACC Scientific Statement, we provide an in-depth and updated examination of the epidemiology, pathophysiology, diagnosis, and treatment of HFpEF.

Ventricular stiffening and chamber contracture in heart failure with higher ejection fraction

AIMS

Ancillary analyses from clinical trials have suggested reduced efficacy for neurohormonal antagonists among patients with heart failure and preserved ejection fraction (HFpEF) and higher ranges of ejection fraction (EF).

METHODS AND RESULTS

A total of 621 patients with HFpEF were grouped into those with low-normal left ventricular EF (LVEF) (HFpEF<65% , n = 319, 50% ≤ LVEF <65%) or HFpEF≥65% (n = 302, LVEF ≥65%), and compared with 149 age-matched controls undergoing comprehensive echocardiography and invasive cardiopulmonary exercise testing. A sensitivity analysis was performed in a second non-invasive community-based cohort of patients with HFpEF (n = 244) and healthy controls without cardiovascular disease (n = 617). Patients with HFpEF≥65% had smaller left ventricular (LV) end-diastolic volume than HFpEF<65% , but LV systolic function assessed by preload recruitable stroke work and stroke work/end-diastolic volume was similarly impaired. Patients with HFpEF≥65% displayed an end-diastolic pressure-volume relationship (EDPVR) that was shifted leftward, with increased LV diastolic stiffness constant β, in both invasive and community-based cohorts. Cardiac filling pressures and pulmonary artery pressures at rest and during exercise were similarly abnormal in all EF subgroups. While patients HFpEF≥57% displayed leftward shifted EDPVR, those with HFpEF<57% had a rightward shifted EDPVR more typical of heart failure with reduced EF.

CONCLUSION

Most pathophysiologic differences in patients with HFpEF and higher EF are related to smaller heart size, increased LV diastolic stiffness, and leftward shift in the EDPVR. These findings may help to explain the absence of efficacy for neurohormonal antagonists in this group and raise a new hypothesis, that interventions to stimulate eccentric LV remodelling and enhance diastolic capacitance may be beneficial for patients with HFpEF and EF in the higher range.

[Mechano-energetic defects in heart failure]

Heart failure is characterized by defects in excitation-contraction coupling, energetic deficit and oxidative stress. The energy for cardiac contraction and relaxation is provided in mitochondria, whose function is tightly regulated by excitation-contraction coupling in cardiac myocytes. In heart failure with reduced ejection fraction (HFrEF), alterations in the ion balance in cardiac myocytes impair mitochondrial Ca²⁺ uptake, which is required for activation of the Krebs cycle, causing an energetic deficit and oxidative stress in mitochondria. Recent clinical studies suggest that in heart failure with preserved ejection fraction (HFpEF), in stark contrast to HFrEF, hypercontractility often occurs as an attempt to compensate for a pathological increase in systemic and pulmonary vascular resistance. This hypercontractility increases cardiac energy and oxygen demands at rest and reduces the contractile, diastolic and coronary reserves, preventing an adequate increase in cardiac output during exercise. Moreover, increased contractility causes long-term maladaptive remodeling processes due to oxidative stress and redox-sensitive prohypertrophic signaling pathways. As overweight and diabetes, particularly in the interplay with hemodynamic stress, are important risk factors for the development of HFpEF, interventions targeting metabolism in particular could ameliorate the development and progression of HFpEF.

Genetic causes of heart failure with preserved ejection fraction: emerging pharmacological treatments

Heart failure with preserved ejection fraction (HFpEF) is a major driver of cardiac morbidity and mortality in developed countries, due to ageing populations and the increasing prevalence of comorbidities. While heart failure with reduced ejection fraction is dominated by left ventricular impairment, HFpEF results from a complex interplay of cardiac remodelling, peripheral circulation, and concomitant features including age, hypertension, obesity, and diabetes. In an important subset, however, HFpEF is subtended by specific diseases of the myocardium that are genetically determined, have distinct pathophysiology, and are increasingly amenable to targeted, innovative treatments. While each of these conditions is rare, they collectively represent a relevant subset within HFpEF cohorts, and their prompt recognition has major consequences for clinical practice, as access to dedicated, disease-specific treatments may radically change the quality of life and outcome. Furthermore, response to standard heart failure treatment will generally be modest for these individuals, whose inclusion in registries and trials may dilute the perceived efficacy of treatments targeting mainstream HFpEF. Finally, a better understanding of the molecular underpinnings of monogenic myocardial disease may help identify therapeutic targets and develop innovative treatments for selected HFpEF phenotypes of broader epidemiological relevance. The field of genetic cardiomyopathies is undergoing rapid transformation due to recent, groundbreaking advances in drug development, and deserves greater awareness within the heart failure community. The present review addressed existing and developing therapies for genetic causes of HFpEF, including hypertrophic cardiomyopathy, cardiac amyloidosis, and storage diseases, discussing their potential impact on management and their broader implications for our understanding of HFpEF at large.

Unfavourable outcomes in patients with heart failure with higher preserved left ventricular ejection fraction

AIMS

Newly introduced drugs for heart failure (HF) have been reported to improve the prognosis of HF with preserved ejection fraction (HFpEF) in the lower range of left ventricular ejection fraction (LVEF). We hypothesized that a higher LVEF is related to an unfavourable prognosis in patients with HFpEF.

METHODS AND RESULTS

We tested this hypothesis by analysing the data from a prospective multicentre cohort study in 255 patients admitted to the hospital due to decompensated HF (LVEF > 40% at discharge). The primary endpoint of this study was a composite outcome of all-cause death and readmission due to HF, and the secondary endpoint was readmission due to HF. LVEF and the mitral E/e' ratio were measured using echocardiography. In multicovariate parametric survival time analysis, LVEF [hazard ratio (HR) = 1.046 per 1% increase, P = 0.001], concurrent atrial fibrillation (AF) (HR = 3.203, P < 0.001), and E/e' (HR = 1.083 per 1.0 increase, P < 0.001) were significantly correlated with the primary endpoint. In addition to these covariates, angiotensin-converting enzyme inhibitor (ACEI)/angiotensin receptor blocker (ARB) use was significantly correlated with the secondary endpoint (HR = 0.451, P = 0.008). Diagnostic performance plot analysis demonstrated that the discrimination threshold value for LVEF that could identify patients prone to reaching the primary endpoint was ≥57.2%. The prevalence of AF or E/e' ratio did not differ significantly between patients with LVEF ≥ 58% and with 40% < LVEF < 58%.

CONCLUSION

A higher LVEF is independently related to poor prognosis in patients with HFpEF, in addition to concurrent AF and an elevated E/e' ratio. ACEI/ARB use, in contrast, was associated with improved prognosis, especially with regard to readmission due to HF.

CLINICAL TRIAL REGISTRATION

https://www.umin.ac.jp/ctr/index.htm.

UNIQUE IDENTIFIER

UMIN000017725.

Influence of temporal resolution on computed tomography feature-tracking strain measurements

PURPOSE

Temporal resolution significantly affects strain values demonstrated by Magnetic resonance feature-tracking and speckle-tracking echocardiography. We investigated the influence of R-R interval reconstruction increments on left ventricular (LV) and left atrial (LA) strain measurements of Computed tomography feature-tracking (CT-FT).

METHODS

Subjects who underwent retrospective electrocardiogram-gated coronary CT angiography (CCTA) were retrospectively included, and CCTA images were reconstructed in 5% and 10% steps throughout the entire cardiac cycle (0-100% R-R interval). LV global longitudinal strain (GLS), circumferential strain (GCS), radial strain (GRS), LA GLS, ejection fraction (EF), and left atrioventricular coupling indices were computed. We evaluated the consistency and variability of continuous variables between the two reconstruction increment groups, the demarcation between the LA conduit and contraction phases, and observer reproducibility in 20 randomly selected participants.

RESULTS

Eighty-one participants with or without cardiac disease were included. The reconstruction increment of the R-R interval significantly affected the CT-FT-derived strain values. The 5% R-R increment resulted in significantly larger absolute strain values. LV GRS had the greatest difference between the two groups. In the subgroups with heart rates greater than 80 beats per minute or impaired cardiac function, group differences were attenuated, especially for LV GLS, LV GRS, and LA GLS. The prevalence of definite demarcation between the LA conduit and contraction phases was significantly higher in the 5% R-R reconstruction increment group than in the 10% R-R reconstruction increment group. The average heart rate during CCTA scanning was a strong risk factor for indefinite demarcation, which is independent of LVEF. As average heart rate increased, so did the incidence of indefinite demarcation between the LA conduit and contraction phases. The observer reproducibility of LV and LA strain values was independent of the R-R reconstruction increment.

CONCLUSION

Reconstruction increment of the R-R interval is an important source of variation in LV and LA CT-FT strain values, especially with low heart rate and preserved cardiac function. It is essential to control the heart rate and apply a narrow R-R reconstruction increment to quantify phasic LA strain.