Relationship Between Focal and Diffuse Fibrosis Assessed by CMR and Clinical Outcomes in Heart Failure With Preserved Ejection Fraction

Potential of 68Ga-FAPI-04 PET/MR to predict worsening renal function after acute ST-elevation myocardial infarction

PURPOSE

The fibroblast activation protein inhibitor-04 (FAPI-04) specifically binds to the FAP of activated myocardial fibroblasts, which makes 68Ga-labelled FAPI-04 (68Ga-FAPI-04) positron emission tomography (PET)/magnetic resonance (MR) a new potential imaging technique for the evaluation of myocardial fibrosis. This study aimed to evaluate the potential value of 68Ga-FAPI-04 PET/MR in assessing and predicting changes in renal function in patients with acute ST-elevation myocardial infarction (STEMI).

METHODS

Thirty-three patients with STEMI were included in this study. 68Ga-FAPI-04 PET/MR and cardiac magnetic resonance were performed before discharge in all patients. Worsening renal function(WRF) was defined as ≥20% decrease in estimated glomerular filtration rate(eGFR) from baseline to 12 months.

RESULTS

The WRF group demonstrated higher 68Ga-FAPI-04 uptake volume (UV) at baseline than the non-WRF group(P = 0.009). 68Ga-FAPI-04 UV at baseline was correlated with follow-up eGFR (r = -0.493, P = 0.004). 68Ga-FAPI-04 UV at baseline was a significant predictor of WRF (OR = 1.014, P = 0.029) at 12 months after STEMI.

CONCLUSIONS

As an effective tool to non-invasively quantify myocardial fibroblast activation, 68Ga-FAPI-04 PET/MR has potential value for assessing and predicting worsening renal function in patients with STEMI.

Sudden Cardiac Death Risk Stratification in Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) poses a significant clinical challenge, with sudden cardiac death (SCD) emerging as one of the leading causes of mortality. Despite advancements in cardiovascular medicine, predicting and preventing SCD in HFpEF remains complex due to multifactorial pathophysiological mechanisms and patient heterogeneity. Unlike heart failure with reduced ejection fraction, where impaired contractility and ventricular remodeling predominate, HFpEF pathophysiology involves heavy burden of comorbidities such as hypertension, obesity, and diabetes. Diverse mechanisms, including diastolic dysfunction, microvascular abnormalities, and inflammation, also contribute to distinct disease and SCD risk profiles. Various parameters such as clinical factors and electrocardiogram features have been proposed in SCD risk assessment. Advanced imaging modalities and biomarkers offer promise in risk prediction, yet comprehensive risk stratification models specific to HFpEF ar0e lacking. This review offers recent evidence on SCD risk factors and discusses current therapeutic strategies aimed at reducing SCD risk in HFpEF.

Prognostic significance of left atrial strain combined with left ventricular strain using cardiac magnetic resonance feature tracking in patients with heart failure with preserved ejection fraction

We aimed to evaluate the prognostic value of left ventricular global longitudinal strain (LVGLS) and left atrial strain (LAS) obtained from magnetic resonance imaging (MRI) feature tracking in patients with heart failure with preserved ejection fraction (HFpEF). We retrospectively enrolled consecutive patients with HFpEF admitted to our hospital who underwent cardiac MRI. LVGLS and LAS were obtained from cine MRI by feature tracking. The end point was defined as a composite of all-cause death, myocardial infarction, and hospitalization due to decompensated HF. One-hundred patients with HFpEF were enrolled. Mean LVGLS and LAS were - 13.7 ± 3.7% and 22.5 ± 11.6%, respectively. During follow-up of 4.4 ± 1.9 years, 24 events occurred. Multivariate Cox proportional hazards model analysis demonstrated LAS was independently associated with adverse cardiac events. Kaplan-Meier curve analysis revealed that the patients with both LVGLS and LAS worse than the median (LVGLS ≥ - 12.2% and LAS ≤ 13.8%) had a significantly lower event-free rate compared to those with preserved strain (Log-rank P < 0.001). Simultaneous assessment of LVGLS and LAS using MRI was useful for risk stratification in the patients with HFpEF.

Preventive and Therapeutic Effects of Crocetin in Rats with Heart Failure

Gardenia is both a food and medicine plant. It is widely used for cardiovascular protection, and its main bioactive ingredient is crocetin. This study aims to observe the therapeutic effects of crocetin on chronic heart failure in rats induced by various etiologies. It further compares the efficacy differences between preventative and treatment administration, varying dosages, and treatment durations, to provide improved guidance for medication in heart failure rats and determine which categories of chronic heart failure rats might benefit most from crocetin. Chronic heart failure models induced by abdominal aorta constriction, renal hypertension, and coronary artery ligation were constructed. By examining cardiac function, blood biochemistry, and histopathology, the study assessed the preventive and therapeutic effects of crocetin on load-induced and myocardial ischemia-induced heart failure. The results showed that in all three models, both treatment and preventative administration of crocetin significantly improved chronic heart failure in rats, especially in preventative administration. The results indicate crocetin may be beneficial for improving symptoms and functional capacity in rats with heart failure. Furthermore, long-term administration was more effective than short-term administration across all three rat models, with therapeutic onset observed over 6 weeks.

Prognostic value of measurement of myocardial extracellular volume using dual-energy CT in heart failure with preserved ejection fraction

Diffuse myocardial fibrosis is associated with adverse outcomes in heart failure with preserved ejection fraction (HFpEF). Dual-energy CT (DECT) can noninvasively assess myocardial fibrosis by quantification of extracellular volume (ECV) fraction. This study evaluated the association between ECV measured by DECT and clinical outcomes in patients with HFpEF. 125 hospitalized HFpEF patients were enrolled in this retrospective cohort study. ECV was measured using DECT with late iodine enhancement. The composite endpoint was defined as HFpEF hospitalization and all-cause mortality during the follow-up. During the median follow-up of 10.4 months, 34 patients (27.20%) experienced the composite outcomes, including 5 deaths; and 29 HFpEF hospitalizations. The higher DECT-ECV group had higher rates of composite outcomes than the low ECV group (log-rank X2 = 6.818, P = 0.033). In multivariate Cox regression analysis, the ECV (HR 1.17, 95% CI 1.06-1.30, P = 0.001) and NT-pro BNP (HR 2.83, 95% CI 1.16-6.88, P = 0.022) were independent risk factors for the adverse outcomes. Myocardial ECV measured using DECT was an independent risk factor for adverse outcomes in patients with HFpEF.

Myocardial fibrosis and prognosis in heart failure with preserved ejection fraction: a pooled analysis of 12 cohort studies

OBJECTIVES

Heart failure with preserved ejection fraction (HFpEF) is a syndrome with significant clinical heterogeneity. Myocardial fibrosis has been considered a common pathological process in the development and progress of HFpEF. This study aimed to consolidate data on the prognostic effect of myocardial fibrosis, evaluated by cardiovascular magnetic resonance (CMR) imaging in patients with HFpEF.

METHODS

Three medical databases were searched for potentially related articles up to February 28, 2023. Cohort studies reporting associations between myocardial fibrosis and risk of all-cause mortality or composite major adverse cardiac outcomes (MACE) were included. Cardiac fibrosis was evaluated by CMR metrics, including late gadolinium enhancement (LGE) or myocardial extracellular volume (ECV). The hazard ratios (HRs) and 95% confidence intervals (CI) of the outcomes for higher myocardial fibrosis were calculated.

RESULTS

Twelve studies with 2787 patients with HFpEF were included for analysis. After a median follow-up duration of 31.2 months, a higher level of cardiac fibrosis was associated with a significant increase in the risk of MACE (HR = 1.34, 95% CI = 1.14-1.57) and all-cause mortality (HR = 1.74, 95% CI = 1.27-2.39), respectively. Furthermore, the increased risk of outcomes was both observed when cardiac fibrosis was defined according to LGE or ECV, respectively.

CONCLUSIONS

Higher burden of myocardial fibrosis evaluated by CMR can predict a poor prognosis in patients with HFpEF. Evaluation of LGE or ECV based on CMR could be recommended in these patients for risk stratification and guiding further treatment.

CLINICAL RELEVANCE STATEMENT

Inclusion of cardiovascular magnetic resonance examination in the diagnostic and risk-evaluation algorithms in patients with heart failure with preserved ejection fraction should be considered in clinical practice and future studies.

KEY POINTS

• Myocardial fibrosis is a common pathological process in heart failure with preserved ejection fraction. • A higher myocardial fibrosis burden on cardiac magnetic resonance predicts a poor prognosis in patients with heart failure with preserved ejection fraction. • Evaluation of myocardial fibrosis may be useful in patients with heart failure with preserved ejection fraction for risk stratification and treatment guidance.

Is atrial fibrillation in HFpEF a distinct phenotype? Insights from multiparametric MRI and circulating biomarkers

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) and atrial fibrillation (AF) frequently co-exist. There is a limited understanding on whether this coexistence is associated with distinct alterations in myocardial remodelling and mechanics. We aimed to determine if patients with atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF) represent a distinct phenotype.

METHODS

In this secondary analysis of adults with HFpEF (NCT03050593), participants were comprehensively phenotyped with stress cardiac MRI, echocardiography and plasma fibroinflammatory biomarkers, and were followed for the composite endpoint (HF hospitalisation or death) at a median of 8.5 years. Those with AF were compared to sinus rhythm (SR) and unsupervised cluster analysis was performed to explore possible phenotypes.

RESULTS

136 subjects were included (SR = 75, AF = 61). The AF group was older (76 ± 8 vs. 70 ± 10 years) with less diabetes (36% vs. 61%) compared to the SR group and had higher left atrial (LA) volumes (61 ± 30 vs. 39 ± 15 mL/m2, p < 0.001), lower LA ejection fraction (EF) (31 ± 15 vs. 51 ± 12%, p < 0.001), worse left ventricular (LV) systolic function (LVEF 63 ± 8 vs. 68 ± 8%, p = 0.002; global longitudinal strain 13.6 ± 2.9 vs. 14.7 ± 2.4%, p = 0.003) but higher LV peak early diastolic strain rates (0.73 ± 0.28 vs. 0.53 ± 0.17 1/s, p < 0.001). The AF group had higher levels of syndecan-1, matrix metalloproteinase-2, proBNP, angiopoietin-2 and pentraxin-3, but lower level of interleukin-8. No difference in clinical outcomes was observed between the groups. Three distinct clusters were identified with the poorest outcomes (Log-rank p = 0.029) in cluster 2 (hypertensive and fibroinflammatory) which had equal representation of SR and AF.

CONCLUSIONS

Presence of AF in HFpEF is associated with cardiac structural and functional changes together with altered expression of several fibro-inflammatory biomarkers. Distinct phenotypes exist in HFpEF which may have differing clinical outcomes.

Fibroblasts and immune cells: at the crossroad of organ inflammation and fibrosis

The immune and fibrotic responses have evolved to work in tandem to respond to pathogen clearance and promote tissue repair. However, excessive immune and fibrotic responses lead to chronic inflammation and fibrosis, respectively, both of which are key pathological drivers of organ pathophysiology. Fibroblasts and immune cells are central to these responses, and evidence of these two cell types communicating through soluble mediators or adopting functions from each other through direct contact is constantly emerging. Here, we review complex junctions of fibroblast-immune cell cross talk, such as immune cell modulation of fibroblast physiology and fibroblast acquisition of immune cell-like functions, as well as how these systems of communication contribute to organ pathophysiology. We review the concept of antigen presentation by fibroblasts among different organs with different regenerative capacities, and then focus on the inflammation-fibrosis axis in the heart in the complex syndrome of heart failure. We discuss the need to develop anti-inflammatory and antifibrotic therapies, so far unsuccessful to date, that target novel mechanisms that sit at the crossroads of the fibrotic and immune responses.

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

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

Ling-Gui-Qi-Hua formula alleviates left ventricular myocardial fibrosis in rats with heart failure with preserved ejection fraction by blocking the transforming growth factor-β1 /Smads signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Ling-Qui-Qi-Hua (LGQH) decoction, composed of Poria cocos (Schw.) Wolf, Cinnamomum cassia (L.) J. Presl, Paeonia veitchii Lynch, and Atractylodes macrocephala Koidz., is a compound formula derived from Ling-Gui-Zhu-Gan decoction recorded in the Treatise on Febrile and Miscellaneous. It has shown cardioprotective effects on patients or rats with heart failure with preserved ejection fraction (HFpEF). Nevertheless, the active ingredients of LGQH and its anti-fibrotic mechanism remain unknown.

AIM OF THE STUDY

To determine the active ingredients in LGQH decoction and verify that LGQH decoction may inhibit left ventricular (LV) myocardial fibrosis in HFpEF rats by blocking the transforming growth factor-β1 (TGF-β1)/Smads signaling pathway from the perspective of animal experiments.

MATERIALS AND METHODS

First, liquid chromatography-mass spectrometry (LC-MS) technology was used to identify active components in the LGQH decoction. Secondly, a rat model of the metabolic syndrome-associated HFpEF phenotype was established and subsequently received LGQH intervention. The mRNA and protein expression of targets in the TGF-β1/Smads pathway were detected by quantitative real-time polymerase chain reaction and western blot analysis. Finally, molecular docking was conducted to examine the interactions between the active ingredients in the LGQH decoction and key proteins of the TGF-β1/Smads pathways.

RESULTS

According to LC-MS analysis, the LGQH decoction contained 13 active ingredients. In animal experiments, LGQH attenuated LV hypertrophy, enlargement, and diastolic function in HEpEF rats. Mechanically, LGQH not only down-regulated TGF-β1, Smad2, Smad3, Smad4, α-SMA, Coll I, and Coll III mRNA expressions and TGF-β1, Smad2, Smad3, P-Smad2/Smad3, Smad4, α-SMA, and Coll I protein expressions, but also up-regulated Smad7 mRNA and protein expressions, which ultimately led to myocardial fibrosis. Furthermore, molecular docking confirmed that 13 active ingredients in the LGQH decoction have excellent binding activities to the critical targets of the TGF-β1/Smads pathway.

CONCLUSION

LGQH is a modified herbal formulation with multiple active ingredients. It might alleviate LV remodeling and diastolic dysfunction and inhibit LV myocardial fibrosis by blocking TGF-β1/Smads pathways in HFpEF rats.

Salvianolic acid A alleviates heart failure with preserved ejection fraction via regulating TLR/Myd88/TRAF/NF-κB and p38MAPK/CREB signaling pathways

Heart failure with preserved ejection fraction (HFpEF) is a morbid, fatal, and common syndrome for which lack of evidence-based therapies. Salvianolic acid A (SAA), a major active ingredient of Salvia miltiorrhiza Burge, has shown potential to protect against cardiovascular diseases. This study aims to elucidate whether SAA possessed therapeutic activity against HFpEF and explore the potential mechanism. HFpEF mouse model was established infusing a combination of high-fat diet (HFD) and Nω-nitro-L-arginine methyl ester (L-NAME) for 14 weeks. After 10 weeks of feeding, HFpEF mice were given SAA (2.5, 5, 10 mg/kg) via oral gavage for four weeks. Body weight, blood pressure, blood lipids, glucose tolerance, exercise performance, cardiac systolic/diastolic function, cardiac pathophysiological changes, and inflammatory factors were assessed. Experimental results showed that SAA reduced HFpEF risk factors, such as body weight gain, glucose intolerance, lipid disorders, and increased exercise tolerance in HFpEF mice. Moreover, SAA not only relieved myocardial hypertrophy and fibrosis by reducing interventricular septal wall thickness, left ventricular posterior wall thickness, left ventricular mass, heart index, cardiomyocyte cross-sectional area and cardiac collagen content, but also improved cardiac diastolic function via reducing E/E' ratio. Finally, SAA inhibited TLR2/TLR4-mediated Myd88 activation and its downstream molecules TRAF6 and IRAK4, which decreases the release of proinflammatory cytokines and mediators through NF-κB and p38 MAPK pathways. In conclusion, SAA could attenuate cardiac inflammation and cardiac disfunction by TLR/Myd88/TRAF/NF-κB and p38MAPK/CREB signaling pathways in HFpEF mice, which provides evidence for SAA as a potential drug for treatment of HFpEF in clinic.

Association between omentin-1 and heart failure with preserved ejection fraction in Chinese elderly patients

BACKGROUND

Omentin-1 is a novel adipokine and is associated with chronic inflammation and cardiovascular diseases. However, it remains unclear whether omentin-1 levels are associated with diagnostic significance in elderly patients with heart failure with preserved ejection fraction (HFpEF). This study aimed to investigate the correlation between omentin-1 and HFpEF in Chinese elderly patients.

HYPOTHESIS

Omentin-1 may be invovled in HFpEF and there may be a difference of omentin-1 levels between HFpEF and control.

METHODS

217 subjects were selected, including 115 patients with HFpEF and 102 control subjects. Enzyme-linked immuno sorbent assay (ELISA) was used to detect plasma levels of omentin-1, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). The receiver operating characteristics (ROC) curve was used to examine the diagnostic performance of omentin-1 in HFpEF.

RESULTS

The levels of omentin-1 decreased significantly in the HFpEF group (14.02 ± 8.35 vs. 19.74 ± 8.45 ng/mL, p < .001), while NT-proBNP, IL-6, and TNF-α levels were significantly increased in the HFpEF group compared with the control group. Spearman correlation analysis showed that omentin-1 levels were negatively correlated with E/e' (r = -.340, p < .001). The multivariate logistic regression analysis indicated that omentin-1 was an independent protective factor for HFpEF (odd ratio = 0.948, 95% confidence interval [CI] 0.905-0.993, p = .025). Omentin-1 levels were negatively correlated with NT-proBNP (r = -.273, p < .001) and TNF-α (r = -.221, p = .001). Diagnostic efficiency by ROC curve analysis in the patients with HFpEF showed that the area under the curve (AUC) for omentin-1 was equivalent to NT-proBNP (AUC: 0.734, 95%CI 0.667-0.802; AUC: 0.800, 95%CI 0.738-0.861). Subgroup analysis showed that in the patients between the age of 70 and 80, the predictive capability of omentin-1 was stronger than NT-proBNP (AUC: 0.809, 95%CI 0.680-0.937; AUC: 0.674, 95%CI 0.514-0.833).

CONCLUSIONS

Omentin-1 levels which were associated with inflammation, were decreased in the HFpEF patients. It could be regarded as a valuable biomarker for the occurrence and development of HFpEF in elderly patients.

Selvester QRS Score is a Predictor of Mortality in Heart Failure with Preserved Ejection Fraction

BACKGROUND

The Selvester QRS (S-QRS) score on a 12-lead electrocardiogram (ECG) is associated with both the amount of myocardial scar and poor prognosis in myocardial infarction patients. However, its prognostic value in heart failure (HF) with preserved ejection fraction (HFpEF) is unknown.

OBJECTIVE

This study aims to investigate the predictive value of the S-QRS score for mortality in HFpEF.

METHODS

359 patients were retrospectively enrolled in this study. Electrocardiographic, echocardiographic, and laboratory features of the patients were recorded. The simplified S-QRS score was measured and recorded. The mean follow-up time of the patients was 38.1±9.5 months. Statistical significance was set at p < 0.05.

RESULTS

Of 359 patients, 270 were in the survivor group, and 89 were in the deceased group. Age, Hs-CRP, troponin, pro-BNP, left atrial (LA) diameter, LA volume index, QRS duration, Tpe, and S-QRS score were statistically high in the deceased group. In multivariate logistic regression analysis, age, Hs-CRP, NT-proBNP, LA diameter, LA volume index, Tpe, and S-QRS score were shown to be independent risk factors for mortality. In the receiver-operating characteristic (ROC) analysis, the cut-off value of the S-QRS score was 5.5, the sensitivity was 80.8%, and the specificity was 77.2% (AUC:0.880, p:0.00). In Kaplan-Meier analysis, it was found that mortality was higher in the group with S-QRS score ≥ 5.5 than in the group with S-QRS score < 5.5. (Long-rank, p:0.00).

CONCLUSIONS

We think that the S-QRS score can be used as a prognostic indicator of long-term mortality in patients with HFpEF.

Epigenetic Regulation of Fibroblasts and Crosstalk between Cardiomyocytes and Non-Myocyte Cells in Cardiac Fibrosis

Epigenetic mechanisms and cell crosstalk have been shown to play important roles in the initiation and progression of cardiac fibrosis. This review article aims to provide a thorough overview of the epigenetic mechanisms involved in fibroblast regulation. During fibrosis, fibroblast epigenetic regulation encompasses a multitude of mechanisms, including DNA methylation, histone acetylation and methylation, and chromatin remodeling. These mechanisms regulate the phenotype of fibroblasts and the extracellular matrix composition by modulating gene expression, thereby orchestrating the progression of cardiac fibrosis. Moreover, cardiac fibrosis disrupts normal cardiac function by imposing myocardial mechanical stress and compromising cardiac electrical conduction. This review article also delves into the intricate crosstalk between cardiomyocytes and non-cardiomyocytes in the heart. A comprehensive understanding of the mechanisms governing epigenetic regulation and cell crosstalk in cardiac fibrosis is critical for the development of effective therapeutic strategies. Further research is warranted to unravel the precise molecular mechanisms underpinning these processes and to identify potential therapeutic targets.

Differentiating the Prognostic Determinants of Myocardial Steatosis for Heart Failure With Preserved Ejection Fraction by Cardiac Magnetic Resonance Imaging

Background Myocardial steatosis and fibrosis may play a role in the pathophysiology of heart failure with preserved ejection fraction. We therefore investigated the prognostic significance of epicardial fat (epicardial adipose tissue [EAT]) and myocardial diffuse fibrosis. Methods and Results Myocardial fibrosis, estimated as extracellular volume (ECV), and EAT were measured using cardiac magnetic resonance imaging in 163 subjects with heart failure with preserved ejection fraction. We also evaluated cardiac structure and diastolic and systolic function by echocardiography and cardiac magnetic resonance imaging. After 24 months' follow-up, 39 (24%) subjects had experienced cardiovascular events, including hospitalization for heart failure, acute coronary syndrome, and cardiovascular death. Median EAT and mean ECV were significantly higher in subjects with cardiovascular events than survivors (EAT, 35 [25-45] versus 31 [21-38], P=0.006 and ECV, 28.9±3.16% versus 27.2±3.56%, P=0.04). Subjects with high EAT (≥42 g) had increased risk of cardiovascular events (hazard ratio [HR], 2.528 [95% CI, 1.704-4.981]; P=0.032). High ECV (>29%) was also significantly associated with poorer outcomes (HR, 1.647 [95% CI, 1.263-2.548]; P=0.013). With respect to secondary end points, high EAT and high ECV were associated with increased risk of the incident acute coronary syndrome (HR, 1.982 [95% CI, 1.008-4.123]; P=0.049) and hospitalization for heart failure (HR, 1.789 [95% CI, 1.102-6.987]; P=0.033), respectively. Conclusions Our study suggested that increased epicardial fat and ECV detected by cardiac magnetic resonance imaging have an impact on cardiovascular prognosis, in particular acute coronary syndrome and hospitalization for heart failure, respectively.

Effects of empagliflozin on cardiac structure, function and biomarkers in patients with heart failure with preserved ejection fraction: study protocol for a randomised, placebo-controlled prospective trial

INTRODUCTION

Heart failure (HF) with preserved ejection fraction (HFpEF) has become the main type of HF worldwide. Although large randomised controlled studies have demonstrated the beneficial effects of sodium-glucose cotransporter 2 inhibitors among patients with HFpEF, the mechanisms remain unclear. Basic research suggests that empagliflozin inhibits myocardial fibrosis. Myocardial extracellular volume (ECV) can be calculated using cardiac MRI (CMRI), which can reflect the degree of diffuse myocardial fibrosis. Studies show that empagliflozin can reduce ECV and left ventricular mass (LVM) assessed by CMRI in patients with diabetes with coronary heart disease and patients without diabetes with HF with reduced ejection fraction. However, whether empagliflozin reduces ECV and LVM among patients with HFpEF is unclear. This study intends to use CMRI to evaluate ECV and LVM, combined with echocardiography and an assessment of related biomarkers, to determine whether empagliflozin can improve myocardial fibrosis and left ventricular remodelling in patients with HFpEF.

METHODS AND ANALYSIS

This report describes the study design of a prospective, multicentre, randomised, double-blind, placebo-controlled and parallel-group clinical study. A total of 180 participants with HFpEF aged 40-80 years old who meet the inclusion and exclusion criteria will be randomly divided into an empagliflozin treatment group or a placebo control group. The empagliflozin treatment group will receive 10 mg of empagliflozin per day for 6 months in addition to guideline-directed medical treatment, while the control group will receive placebo oral administration with guideline-directed medical therapy for 6 months. The primary outcomes are ECV and LVM changes measured by CMRI after 6 months of treatment.

ETHICS AND DISSEMINATION

The study design is approved by the ethical committee of Beijing Hospital (2022BJYYEC-070-02). The trial is registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn). The trial results will be published in peer-reviewed journals and conferences.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR2200060862).

Imaging characterization of myocardial function, fibrosis, and perfusion in a nonhuman primate model with heart failure-like features

Introduction

The availability of a human-like chronic heart failure (HF) animal model was critical for affiliating development of novel therapeutic drug treatments. With the close physiology relatedness to humans, the non-human primate (NHP) HF model would be valuable to better understand the pathophysiology and pharmacology of HF. The purpose of this work was to present preliminary cardiac image findings using echocardiography and cardiovascular magnetic resonance (CMR) in a HF-like cynomolgus macaque model.

Methods

The NHP diet-induced model developed cardiac phenotypes that exhibited diastolic dysfunction with reduced left ventricular ejection fraction (LVEF) or preserved LVEF. Twenty cynomolgus monkeys with cardiac dysfunction were selected by echocardiography and subsequently separated into two groups, LVEF < 65% (termed as HFrEF, n = 10) and LVEF ≥ 65% with diastolic dysfunction (termed as HFpEF, n = 10). Another group of ten healthy monkeys was used as the healthy control. All monkeys underwent a CMR study to measure global longitudinal strain (GLS), myocardial extracellular volume (ECV), and late gadolinium enhancement (LGE). In healthy controls and HFpEF group, quantitative perfusion imaging scans at rest and under dobutamine stress were performed and myocardial perfusion reserve (MPR) was subsequently obtained.

Results

No LGE was observed in any monkey. Monkeys with HF-like features were significantly older, compared to the healthy control group. There were significant differences among the three groups in ECV (20.79 ± 3.65% in healthy controls; 27.06 ± 3.37% in HFpEF group, and 31.11 ± 4.50% in HFrEFgroup, p < 0.001), as well as for stress perfusion (2.40 ± 0.34 ml/min/g in healthy controls vs. 1.28 ± 0.24 ml/min/g in HFpEF group, p < 0.01) and corresponding MPR (1.83 ± 0.3 vs. 1.35 ± 0.29, p < 0.01). After adjusting for age, ECV (p = 0.01) and MPR (p = 0.048) still showed significant differences among the three groups.

Conclusion

Our preliminary imaging findings demonstrated cardiac dysfunction, elevated ECV, and/or reduced MPR in this HF-like NHP model. This pilot study laid the foundation for further mechanistic research and the development of a drug testing platform for distinct HF pathophysiology.

Left-to-right ventricular volume ratio and outcome in heart failure with preserved ejection fraction

BACKGROUND

Age-specific and gender-specific reference values for left ventricular (LV) and right ventricle volumes are available. The prognostic implications of the ratio between these volumes in heart failure and preserved ejection fraction (HFpEF) have never been evaluated.

METHODS

We examined all HFpEF outpatients undergoing a cardiac magnetic resonance from 2011 to 2021. The left-to-right ventricular volume ratio (LRVR) was defined as the ratio between the LV and right ventricle end-diastolic volume indexes (LVEDVi/RVEDVi).

RESULTS

Among 159 patients [median age 58 years (interquartile range 49-69), 64% men, LV ejection fraction 60% (54-70%)] the median LRVR was 1.21 (1.07-1.40). Over 3.5 years (1.5-5.0), 23 patients (15%) experienced all-cause death or heart failure hospitalization, and 22 (14%) cardiovascular death or heart failure hospitalization. The risk of all-cause death or heart failure hospitalization increased with an LRVR less than 1.0 or at least 1.4. An LRVR less than 1.0 was associated with a higher risk of all-cause death or heart failure hospitalization [hazard ratio 5.95, 95% confidence interval (CI) 1.67-21.28; P = 0.006] and cardiovascular death or heart failure hospitalization (hazard ratio 5.68, 95% CI 1.58-20.35; P = 0.008) as compared with LRVR 1.0-1.3. Furthermore, an LRVR at least 1.4 was associated with a higher risk of all-cause death or heart failure hospitalization (hazard ratio 4.10, 95% CI 1.58-10.61; P = 0.004) and cardiovascular death or heart failure hospitalization (hazard ratio 3.71, 95% CI 1.41-9.79; P = 0.008) as compared with LRVR 1.0-1.3. These results were confirmed in patients without dilation of either ventricle.

CONCLUSION

LRVR values less than 1.0 or at least 1.4 are associated with worse outcomes in HFpEF. LRVR may become a valuable tool for risk prediction in HFpEF.

A rat model of metabolic syndrome-related heart failure with preserved ejection fraction phenotype: pathological alterations and possible molecular mechanisms

Background

Heart failure with preserved ejection fraction (HFpEF) represents a syndrome involving multiple pathophysiologic disorders and clinical phenotypes. This complexity makes it challenging to develop a comprehensive preclinical model, which presents an obstacle to elucidating disease mechanisms and developing new drugs. Metabolic syndrome (MetS) is a major phenotype of HFpEF. Thus, we produced a rat model of the MetS-related HFpEF phenotype and explored the molecular mechanisms underpinning the observed pathological changes.

Methods

A rat model of the MetS-related HFpEF phenotype was created by feeding spontaneously hypertensive rats a high-fat-salt-sugar diet and administering streptozotocin solution intraperitoneally. Subsequently, pathological changes in the rat heart and their possible molecular mechanisms were explored.

Results

The HFpEF rats demonstrated primary features of MetS, such as hypertension, hyperglycemia, hyperlipidemia, insulin resistance, and cardiac anomalies, such as left ventricular (LV) remodeling and diastolic impairment, and left atrial dilation. Additionally, inflammation, myocardial hypertrophy, and fibrosis were observed in LV myocardial tissue, which may be associated with diverse cellular and molecular signaling cascades. First, the inflammatory response might be related to the overexpression of inflammatory regulators (growth differentiation factor 15 (GDF-15), intercellular adhesion molecule-1 (ICAM-1), and vascular endothelial cell adhesion molecule-1 (VCAM-1)). Secondly, phosphorylated glycogen synthase kinase 3β (GSK-3β) may stimulate cardiac hypertrophy, which was regulated by activated -RAC-alpha serine/threonine-protein kinase (AKT). Finally, the transforming growth factor-β1 (TGF-β1)/Smads pathway might regulate collagen production and fibroblast activation, promoting myocardial fibrosis.

Conclusion

The HFpEF rat replicates the pathology and clinical presentation of human HFpEF with MetS and may be a reliable preclinical model that helps elucidate HFpEF pathogenesis and develop effective treatment strategies.

Impact of polyphenols on heart failure and cardiac hypertrophy: clinical effects and molecular mechanisms

Polyphenols are abundant in regular diets and possess antioxidant, anti-inflammatory, anti-cancer, neuroprotective, and cardioprotective effects. Regarding the inadequacy of the current treatments in preventing cardiac remodeling following cardiovascular diseases, attention has been focused on improving cardiac function with potential alternatives such as polyphenols. The following online databases were searched for relevant orginial published from 2000 to 2023: EMBASE, MEDLINE, and Web of Science databases. The search strategy aimed to assess the effects of polyphenols on heart failure and keywords were "heart failure" and "polyphenols" and "cardiac hypertrophy" and "molecular mechanisms". Our results indicated polyphenols are repeatedly indicated to regulate various heart failure-related vital molecules and signaling pathways, such as inactivating fibrotic and hypertrophic factors, preventing mitochondrial dysfunction and free radical production, the underlying causes of apoptosis, and also improving lipid profile and cellular metabolism. In the current study, we aimed to review the most recent literature and investigations on the underlying mechanism of actions of different polyphenols subclasses in cardiac hypertrophy and heart failure to provide deep insight into novel mechanistic treatments and direct future studies in this context. Moreover, due to polyphenols' low bioavailability from conventional oral and intravenous administration routes, in this study, we have also investigated the currently accessible nano-drug delivery methods to optimize the treatment outcomes by providing sufficient drug delivery, targeted therapy, and less off-target effects, as desired by precision medicine standards.

Relationship between diffuse fibrosis assessed by CMR and depressed myocardial strain in different stages of heart failure

OBJECTIVES

To investigate the extent of the left ventricular (LV) diffuse myocardial fibrosis and the association with the degree of impaired myocardial strain in different stages of heart failure.

BACKGROUND

The increased diffuse myocardial fibrosis impairs the LV systolic and diastolic function. Previous studies found that the global longitudinal strain (GLS) impacted survival in patients with heart failure with preserved ejection fraction (HFpEF). However, limited data are available regarding the association between the degree of diffuse myocardial fibrosis and the severity of impaired myocardial strain in HFpEF.

METHODS

Sixty-six consecutive participants with heart failure (HF), and 15 healthy controls underwent cardiac magnetic resonance (CMR) examination. T1 mapping to calculate extracellular volume fractions (ECV) were used to assess diffuse myocardial fibrosis. ECV and myocardial strains were compared among the 3 groups. Associations between these two factors were also explored.

RESULTS

The patients with HFpEF showed increased myocardial ECV fractions (32.9 % ± 3.7 % vs. 29.2 % ± 2.9 %, p < 0.001) compared with the control group. The patients with HFm + rEF also had increased myocardial ECV fractions (36.8 % ± 5.4 % vs. 32.9 % ± 3.7 %, p < 0.001) compared with HFpEF. The myocardial ECV was significantly correlated with the GLS (r = 0.422, p = 0.020), global circumferential strain (GCS) (r = 0.491, p = 0.006), and global radial strain (GRS) (r = -0.533, p = 0.002) in the HFpEF groups, but no significant correlation was found in the HFm + rEF group (GLS: r = -0.002, p = 0.990; GCS: r = 0.153, p = 0.372; GRS: r = 0.070, p = 0.685) CONCLUSIONS: In patients with HF, only patients with HFpEF exhibited a significant correlation between increased diffuse myocardial fibrosis and impaired myocardial strain. Diffuse myocardial fibrosis plays a unique role in affecting myocardial strain in patients with HFpEF.

Survival prediction of heart failure patients using motion-based analysis method

BACKGROUND AND OBJECTIVE

Survival prediction of heart failure patients is critical to improve the prognostic management of the cardiovascular disease. The existing survival prediction methods focus on the clinical information while lacking the cardiac motion information. we propose a motion-based analysis method to predict the survival risk of heart failure patients for aiding clinical diagnosis and treatment.

METHODS

We propose a motion-based analysis method for survival prediction of heart failure patients. First, our method proposes the hierarchical spatial-temporal structure to capture the myocardial border. It promotes the model discrimination on border features. Second, our method explores the dense optical flow structure to capture motion fields. It improves the tracking capability on cardiac images. The cardiac motion information is obtained by fusing boundary information and motion fields of cardiac images. Finally, our method proposes the multi-modality deep-cox structure to predict the survival risk of heart failure patients. It improves the survival probability of heart failure patients.

RESULTS

The motion-based analysis method is confirmed to be able to improve the survival prediction of heart failure patients. The precision, recall, F1-score, and C-index are 0.8519, 0.8333, 0.8425, and 0.8478, respectively, which is superior to other state-of-the-art methods.

CONCLUSIONS

The experimental results show that the proposed model can effectively predict survival risk of heart failure patients. It facilitates the application of robust clinical treatment strategies.

Diffuse myocardial fibrosis associates with incident ventricular arrhythmia in implantable cardioverter defibrillator recipients

Background

Diffuse myocardial fibrosis (DMF) quantified by extracellular volume (ECV) may represent a vulnerable phenotype and associate with life threatening ventricular arrhythmias more than focal myocardial fibrosis. This principle remains important because 1) risk stratification for implantable cardioverter defibrillators (ICD) remains challenging, and 2) DMF may respond to current or emerging medical therapies (reversible substrate).

Objectives

To evaluate the association between quantified by ECV in myocardium without focal fibrosis by late gadolinium enhancement (LGE) with time from ICD implantation to 1) appropriate shock, or 2) shock or anti-tachycardia pacing.

Methods

Among patients referred for cardiovascular magnetic resonance (CMR) without congenital disease, hypertrophic cardiomyopathy, or amyloidosis who received ICDs (n=215), we used Cox regression to associate ECV with incident ICD therapy.

Results

After a median of 2.9 (IQR 1.5-4.2) years, 25 surviving patients experienced ICD shock and 44 experienced shock or anti-tachycardia pacing. ECV ranged from 20.2% to 39.4%. No patient with ECV<25% experienced an ICD shock. ECV associated with both endpoints, e.g., hazard ratio 2.17 (95%CI 1.17-4.00) for every 5% increase in ECV, p=0.014 in a stepwise model for ICD shock adjusting for ICD indication, age, smoking, atrial fibrillation, and myocardial infarction, whereas focal fibrosis by LGE and global longitudinal strain (GLS) did not.

Conclusions

DMF measured by ECV associates with ventricular arrhythmias requiring ICD therapy in a dose-response fashion, even adjusting for potential confounding variables, focal fibrosis by LGE, and GLS. ECV-based risk stratification and DMF representing a therapeutic target to prevent ventricular arrhythmia warrant further investigation.

Cardiovascular magnetic resonance phenotyping of heart failure with mildly reduced ejection fraction

AIMS

The 2016 European Society of Cardiology Heart Failure Guidelines defined a new category: heart failure with mid-range ejection fraction (HFmrEF) of 40-49%. This new category was highlighted as having limited evidence and research was advocated into underlying characteristics, pathophysiology, and diagnosis. We used multi-parametric cardiovascular magnetic resonance (CMR) to define the cardiac phenotype of presumed non-ischaemic HFmrEF.

METHODS AND RESULTS

Patients (N = 300, 62.7 ± 13 years, 63% males) with a clinical diagnosis of heart failure with no angina symptoms, history of myocardial infarction, or coronary intervention were prospectively recruited. Patients underwent clinical assessment and CMR including T1 mapping, extracellular volume (ECV) mapping, late gadolinium enhancement, and measurement of myocardial blood flow at rest and maximal hyperaemia. Of 273 patients in the final analysis, 93 (34%) patients were categorized as HFmrEF, 46 (17%) as heart failure with preserved ejection fraction (HFpEF), and 134 (49%) as heart failure with reduced ejection fraction (HFrEF). Nineteen (20%) patients with HFmrEF had evidence of occult ischaemic heart disease. Diffuse fibrosis and hyperaemic myocardial blood flow were similar in HFmrEF and HFpEF, but HFmrEF showed significantly lower native T1 (1311 ± 32 vs. 1340 ± 45 ms, P < 0.001), ECV (24.6 ± 3.2 vs. 26.3 ± 3.1%, P < 0.001), and higher myocardial perfusion reserve (2.75 ± 0.84 vs. 2.28 ± 0.84, P < 0.001) compared with HFrEF.

CONCLUSION

Patients with HFmrEF share most phenotypic characteristics with HFpEF, including the degree of microvascular impairment and fibrosis, but have a high prevalence of occult ischaemic heart disease similar to HFrEF. Further work is needed to confirm how the phenotype of HFmrEF responds to medical therapy.

The role of cardiac magnetic resonance imaging in the assessment of heart failure with preserved ejection fraction

Heart failure (HF) is a major cause of morbidity and mortality worldwide. Current classifications of HF categorize patients with a left ventricular ejection fraction of 50% or greater as HF with preserved ejection fraction or HFpEF. Echocardiography is the first line imaging modality in assessing diastolic function given its practicality, low cost and the utilization of Doppler imaging. However, the last decade has seen cardiac magnetic resonance (CMR) emerge as a valuable test for the sometimes challenging diagnosis of HFpEF. The unique ability of CMR for myocardial tissue characterization coupled with high resolution imaging provides additional information to echocardiography that may help in phenotyping HFpEF and provide prognostication for patients with HF. The precision and accuracy of CMR underlies its use in clinical trials for the assessment of novel and repurposed drugs in HFpEF. Importantly, CMR has powerful diagnostic utility in differentiating acquired and inherited heart muscle diseases presenting as HFpEF such as Fabry disease and amyloidosis with specific treatment options to reverse or halt disease progression. This state of the art review will outline established CMR techniques such as transmitral velocities and strain imaging of the left ventricle and left atrium in assessing diastolic function and their clinical application to HFpEF. Furthermore, it will include a discussion on novel methods and future developments such as stress CMR and MR spectroscopy to assess myocardial energetics, which show promise in unraveling the mechanisms behind HFpEF that may provide targets for much needed therapeutic interventions.

Predictors of myocardial fibrosis and response to anti-fibrotic therapy in heart failure with preserved ejection fraction

Myocardial fibrosis, measured using magnetic resonance extracellular volume (ECV), associates with adverse outcome in heart failure with preserved ejection fraction (HFpEF). In the PIROUETTE (The Pirfenidone in Patients with Heart Failure and Preserved Left Ventricular Ejection Fraction) trial, the novel anti-fibrotic agent pirfenidone reduced myocardial fibrosis. We sought to identify baseline characteristics that associate with myocardial fibrotic burden, the change in myocardial fibrosis over a year, and predict response to pirfenidone in patients with HFpEF. Amongst patients enrolled in the PIROUETTE trial (n = 107), linear regression models were used to assess the relationship between baseline variables and baseline myocardial ECV, with change in myocardial ECV adjusting for treatment allocation, and to identify variables that modified the pirfenidone treatment effect. Body mass index, left atrial reservoir strain, haemoglobin and aortic distensibility were associated with baseline ECV in stepwise modelling, and systolic blood pressure, and log N-terminal pro B-type natriuretic peptide were associated with baseline ECV in clinically-guided modelling. QRS duration, left ventricular mass and presence of an infarct at baseline were associated with an increase in ECV from baseline to week 52. Whilst QRS duration, presence of an infarct, global longitudinal strain and left atrial strain modified the treatment effect of pirfenidone when considered individually, no variable modified treatment effect on multivariable modelling. Baseline characteristics were identified that associate with myocardial fibrosis and predict change in myocardial fibrosis. No variables that independently modify the treatment effect of pirfenidone were identified (PIROUETTE, NCT02932566).

Prevalence and Prognostic Significance of Microvascular Dysfunction in Heart Failure With Preserved Ejection Fraction

BACKGROUND

The pathophysiological and clinical significance of microvascular dysfunction (MVD) in patients with heart failure with preserved ejection fraction (HFpEF) remains uncertain.

OBJECTIVES

The aim of this study was to use cardiovascular magnetic resonance to: 1) quantify coronary microvascular function; 2) examine the relationship between perfusion and fibrosis; and 3) evaluate the impact of MVD and fibrosis on long-term clinical outcomes.

METHODS

In a prospective, observational study, patients with HFpEF and control subjects underwent multiparametric cardiovascular magnetic resonance (comprising assessment of left ventricular volumetry, perfusion, and fibrosis [focal by late gadolinium enhancement and diffuse by extracellular volume]). The primary endpoint was the composite of death or hospitalization with heart failure.

RESULTS

One hundred and one patients with HFpEF (mean age 73 ± 9 years, mean ejection fraction 56% ± 5%) and 43 control subjects (mean age 73 ± 5 years, mean ejection fraction 58% ± 5%) were studied. Myocardial perfusion reserve (MPR) was lower in patients with HFpEF versus control subjects (1.74 ± 0.76 vs 2.22 ± 0.76; P = 0.001). MVD (defined as MPR <2.0) was present in 70% of patients with HFpEF (vs 48% of control subjects; P = 0.014). There was no significant linear correlation between MPR and diffuse fibrosis (r = -0.10; P = 0.473) and no difference in MPR between those with and without focal fibrosis (mean difference -0.03; 95% CI: -0.37 to 0.30). In the HFpEF group, during median follow-up of 3.1 years, there were 45 composite events. MPR was independently predictive of clinical outcome following adjustment for clinical, blood, and imaging parameters (1 SD increase: HR: 0.673 [95% CI: 0.463 to 0.978; P = 0.038]; HR: 0.694 [95% CI: 0.491 to 0.982; P = 0.039]; and HR: 0.690 [95% CI: 0.489 to 0.973; P = 0.034], respectively).

CONCLUSIONS

MVD is highly prevalent among patients with HFpEF and is an independent predictor of prognosis. The lack of correlation between MVD and fibrosis may challenge the assertion of a direct causal link between these entities. (Developing Imaging and Plasma Biomarkers in Describing Heart Failure With Preserved Ejection Fraction [DIAMONDHFpEF]; NCT03050593).

Prognostic Value of Characterizing Myocardial Tissue by Cardiac MRI with T1 Mapping in HFpEF Patients: A Systematic Review and Meta-Analysis

Objectives: Our study aimed at conducting a systematic review and meta-analysis, with the objective of evaluating the prognostic value of T1 mapping techniques via cardiac magnetic resonance (CMR) in heart failure with preserved ejection fraction (HFpEF) patients. Materials and methods: The protocol was prospectively registered in the international prospective register of systematic reviews PROSPERO (registration number CRD42022300991). We searched PubMed, Google Scholar, and EMBASE for studies examining the prognostic value of characterizing myocardial tissue via CMR imaging with T1 mapping in HFpEF. Hazard ratios (HRs) for uniformly defined predictors were pooled for meta-analysis. Results: In total, 7 studies were retrieved from 351 publications for this systematic review and meta-analysis. A total of 1930 patients (mean age of 69.4 years, mean follow-up duration of 25.6 months) was included in the analysis. The meta-analysis demonstrated that higher extracellular volume (ECV) was associated with an increased risk of death and/or hospitalization with heart failure (HF) (HR:1.12; 95% CI: 1.06−1.18; p < 0.0001). After adjusting for baseline characteristics, the higher extent of ECV remained strongly associated with the risk of death and/or hospitalization with HF (HRadjusted: 1.08; 95% CI: 1.04−1.13; p = 0.0001). However, no significant association of native T1 value with risk of death or adverse cardiovascular events was found (HR:1.01; 95% CI: 1.00−1.02; p = 0.21). Conclusion: Assessment of ECV via CMR has an important prognostic value for outcomes of death and/or hospitalization with HF, and can therefore be used as an effective tool for risk stratification of patients with HFpEF.

Advances in Multimodality Cardiovascular Imaging in the Diagnosis of Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a syndrome defined by the presence of heart failure symptoms and increased levels of circulating natriuretic peptide (NP) in patients with preserved left ventricular ejection fraction and various degrees of diastolic dysfunction (DD). HFpEF is a complex condition that encompasses a wide range of different etiologies. Cardiovascular imaging plays a pivotal role in diagnosing HFpEF, in identifying specific underlying etiologies, in prognostic stratification, and in therapeutic individualization. Echocardiography is the first line imaging modality with its wide availability; it has high spatial and temporal resolution and can reliably assess systolic and diastolic function. Cardiovascular magnetic resonance (CMR) is the gold standard for cardiac morphology and function assessment, and has superior contrast resolution to look in depth into tissue changes and help to identify specific HFpEF etiologies. Differently, the most important role of nuclear imaging [i.e., planar scintigraphy and/or single photon emission CT (SPECT)] consists in the screening and diagnosis of cardiac transthyretin amyloidosis (ATTR) in patients with HFpEF. Cardiac CT can accurately evaluate coronary artery disease both from an anatomical and functional point of view, but tissue characterization methods have also been developed. The aim of this review is to critically summarize the current uses and future perspectives of echocardiography, nuclear imaging, CT, and CMR in patients with HFpEF.

Dysregulated Epicardial Adipose Tissue as a Risk Factor and Potential Therapeutic Target of Heart Failure with Preserved Ejection Fraction in Diabetes

Cardiovascular (CV) disease and heart failure (HF) are the leading cause of mortality in type 2 diabetes (T2DM), a metabolic disease which represents a fast-growing health challenge worldwide. Specifically, T2DM induces a cluster of systemic metabolic and non-metabolic signaling which may promote myocardium derangements such as inflammation, fibrosis, and myocyte stiffness, which represent the hallmarks of heart failure with preserved ejection fraction (HFpEF). On the other hand, several observational studies have reported that patients with T2DM have an abnormally enlarged and biologically transformed epicardial adipose tissue (EAT) compared with non-diabetic controls. This expanded EAT not only causes a mechanical constriction of the diastolic filling but is also a source of pro-inflammatory mediators capable of causing inflammation, microcirculatory dysfunction and fibrosis of the underlying myocardium, thus impairing the relaxability of the left ventricle and increasing its filling pressure. In addition to representing a potential CV risk factor, emerging evidence shows that EAT may guide the therapeutic decision in diabetic patients as drugs such as metformin, glucagon-like peptide‑1 (GLP-1) receptor agonists and sodium-glucose cotransporter 2 inhibitors (SGLT2-Is), have been associated with attenuation of EAT enlargement.

A Radiomic MRI based Nomogram for Prediction of Heart Failure with Preserved Ejection Fraction in Systemic Lupus Erythematosus Patients: Insights From a Three-Center Prospective Study

BACKGROUND

Myocardial T1 and extracellular volume (ECV) fraction values have important roles in the prognostication of heart failure with preserved ejection fraction (HFpEF). However, the traditional mean quantification of intensity levels is not sufficient.

PURPOSE

To evaluate a T1 map-based radiomic nomogram as a long-term prognosticator for HFpEF in systemic lupus erythematosus (SLE) patients.

STUDY TYPE

Prospective.

POPULATION

A total of 115 SLE patients and 50 age- and gender-matched controls.

FIELD STRENGTH/SEQUENCE

A 3.0 T scanner; cine imaging, precontrast and post-contrast T1 mapping and T2 mapping sequences.

ASSESSMENT

A radiomic nomogram was developed based on precontrast T1 mapping. Three independent readers assessed and compared the ECV value and the value of the radiomic nomogram for predicting HFpEF in SLE patients.

STATISTICAL TEST

Cox proportional hazard models, Youden index for determining cut-off values for high HFpEF risk vs. low HFpEF risk classification, Kaplan-Meier analysis, intraclass correlation (ICC), and Uno C statistic test.

RESULTS

During a median follow-up of 27 (interquartile range, 19-37) months, 31 SLE patients developed HFpEF. Patients with elevated ECV (≥31%) and a higher output (≥42.7) from the radiomic feature "S_33_sum average" of the precontrast T1 map had a significantly higher risk of developing HFpEF than those who had lower ECV (<31%) and an output <42.7. Patients with a higher "S_33_sum average" value on precontrast T1 map had a significantly increased risk for HFpEF (hazard ratio, 1.363, 95% CI, 1.130-1.645), after adjusting for covariates including ECV and LVEF. Finally, "S_33_sum average" from precontrast T1 mapping had modest but significantly incremental prognostic value over the mean ECV value (Uno C statistic comparing models, 0.860 vs. 0.835).

DATA CONCLUSION

The precontrast T1 map-based radiomic nomogram, as a measure of diffuse myocardial fibrosis was associated with HFpEF and provided modest prognostic value for predicting HFpEF in SLE patients.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 2.

Microvascular Dysfunction in Heart Failure with Preserved Ejection Fraction: Pathophysiology, Assessment, Prevalence and Prognosis

Heart failure with preserved ejection fraction (HFpEF) currently accounts for approximately half of all new heart failure cases in the community. HFpEF is closely associated with chronic lifestyle-related diseases, such as obesity and type 2 diabetes, and clinical outcomes are worse in those with than without comorbidities. HFpEF is pathophysiologically distinct from heart failure with reduced ejection fraction, which may explain, in part, the disparity of treatment options available between the two heart failure phenotypes. The mechanisms underlying HFpEF are complex, with coronary microvascular dysfunction (MVD) being proposed as a potential key driver in its pathophysiology. In this review, the authors highlight the evidence implicating MVD in HFpEF pathophysiology, the diagnostic approaches for identifying MVD (both invasive and non-invasive) and the prevalence and prognostic significance of MVD.

Heart failure with preserved ejection fraction assessed by cardiac magnetic resonance: From clinical uses to emerging techniques

Patients with heart failure with preserved ejection fraction (HFpEF) account for approximately 50% of those with heart failure (HF) and have increased morbidity and mortality when compared to those with HF with reduced ejection fraction. Currently, the pathophysiology and diagnostic criteria for HFpEF remain unclear, contributing significantly to delays in creating a beneficial and tailored treatment that can improve the prognosis of HFpEF. A multitude of studies have exclusively tested and illustrated the diagnostic value of echocardiography imaging in HFpEF; however, a widely-accepted criterion to identify HFpEF using cardiovascular magnetic resonance (CMR) imaging has not been established. As the gold standard for cardiac structural, functional measurement, and tissue characterization, CMR holds great potential for the early discovery of the pathophysiology, diagnosis, and risk stratification of HFpEF. This review aims to comprehensively discuss the diagnostic and prognostic role of CMR parameters in the setting of HFpEF through validated routine and prospective emerging techniques, and provide clinical perspectives for CMR imaging application in HFpEF.

Left Atrial Stiffness Index Independently Predicts Exercise Intolerance and Quality of Life in Older, Obese Patients With Heart Failure With Preserved Ejection Fraction

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is the fastest growing form of HF and is associated with high morbidity and mortality. The primary chronic symptom in HFpEF is exercise intolerance, associated with reduced quality of life. Emerging evidence implicates left atrial (LA) dysfunction as an important pathophysiologic mechanism. Here we extend prior observations by relating LA dysfunction to peak oxygen uptake (peak VO₂), physical function (distance walked in 6 minutes [6MWD]) and quality of life (Kansas City Cardiomyopathy Questionnaire).

METHODS AND RESULTS

We compared 75 older, obese, patients with HFpEF with 53 healthy age-matched controls. LA strain was assessed by magnetic resonance cine imaging using feature tracking. LA function was defined according to its 3 distinct phases, with the LA serving as a reservoir during systole, as a conduit during early diastole, and as a booster pump at the end of diastole. The LA stiffness index was calculated as the ratio of early mitral inflow velocity-to-early annular tissue velocity (E/e', by Doppler ultrasound examination) and LA reservoir strain. HFpEF had a decreased reservoir strain (16.4 ± 4.4% vs 18.2 ± 3.5%, P = .018), lower conduit strain (7.7 ± 3.3% vs 9.1 ± 3.4%, P = .028), and increased stiffness index (0.86 ± 0.39 vs 0.53 ± 0.18, P < .001), as well as decreased peak VO₂, 6MWD, and lower quality of life. Increased LA stiffness was independently associated with impaired peak VO₂ (β = 9.0 ± 1.6, P < .001), 6MWD (β = 117 ± 22, P = .003), and Kansas City Cardiomyopathy Questionnaire score (β = -23 ± 5, P = .001), even after adjusting for clinical covariates.

CONCLUSIONS

LA stiffness is independently associated with impaired exercise tolerance and quality of life and may be an important therapeutic target in obese HFpEF.

REGISTRATION

NCT00959660.

Lipotoxicity: a driver of heart failure with preserved ejection fraction?

Heart failure with preserved ejection fraction (HFpEF) is a growing public health concern, with rising incidence alongside high morbidity and mortality. However, the pathophysiology of HFpEF is not yet fully understood. The association between HFpEF and the metabolic syndrome (MetS) suggests that dysregulated lipid metabolism could drive diastolic dysfunction and subsequent HFpEF. Herein we summarise recent advances regarding the pathogenesis of HFpEF in the context of MetS, with a focus on impaired lipid handling, myocardial lipid accumulation and subsequent lipotoxicity.

Prevalence of Coronary Artery Disease and Coronary Microvascular Dysfunction in Patients With Heart Failure With Preserved Ejection Fraction

Importance

Coronary artery disease (CAD) and coronary microvascular dysfunction (CMD) may contribute to the pathophysiologic characteristics of heart failure with preserved ejection fraction (HFpEF). However, the prevalence of CAD and CMD have not been systematically studied.

Objective

To examine the prevalence of CAD and CMD in hospitalized patients with HFpEF.

Design, Setting, and Participants

A total of 106 consecutive patients hospitalized with HFpEF were evaluated in this prospective, multicenter, cohort study conducted between January 2, 2017, and August 1, 2018; data analysis was performed from March 4 to September 6, 2019. Participants underwent coronary angiography with guidewire-based assessment of coronary flow reserve, index of microvascular resistance, and fractional flow reserve, followed by coronary vasoreactivity testing. Cardiac magnetic resonance imaging was performed with late gadolinium enhancement and assessment of extracellular volume. Myocardial perfusion was assessed qualitatively and semiquantitatively using the myocardial-perfusion reserve index.

Main Outcomes and Measures

The prevalence of obstructive epicardial CAD, CMD, and myocardial ischemia, infarction, and fibrosis.

Results

Of 106 participants enrolled (53 [50%] women; mean [SD] age, 72 [9] years), 75 had coronary angiography, 62 had assessment of coronary microvascular function, 41 underwent coronary vasoreactivity testing, and 52 received cardiac magnetic resonance imaging. Obstructive epicardial CAD was present in 38 of 75 participants (51%, 95% CI, 39%-62%); 19 of 38 (50%; 95% CI, 34%-66%) had no history of CAD. Endothelium-independent CMD (ie, coronary flow reserve <2.0 and/or index of microvascular resistance ≥25) was identified in 41 of 62 participants (66%; 95% CI, 53%-77%). Endothelium-dependent CMD (ie, abnormal coronary vasoreactivity) was identified in 10 of 41 participants (24%; 95% CI, 13%-40%). Overall, 45 of 53 participants (85%; 95% CI, 72%-92%) had evidence of CMD and 29 of 36 (81%; 95% CI, 64%-91%) of those without obstructive epicardial CAD had CMD. Cardiac magnetic resonance imaging findings included myocardial-perfusion reserve index less than or equal to 1.84 (ie, impaired global myocardial perfusion) in 29 of 41 patients (71%; 95% CI, 54%-83%), visual perfusion defect in 14 of 46 patients (30%; 95% CI, 19%-46%), ischemic late gadolinium enhancement (ie, myocardial infarction) in 14 of 52 patients (27%; 95% CI, 16%-41%), and extracellular volume greater than 30% (ie, diffuse myocardial fibrosis) in 20 of 48 patients (42%; 95% CI, 28%-56%). Patients with obstructive CAD had more adverse events during follow-up (28 [74%]) than those without obstructive CAD (17 [46%]).

Conclusions and Relevance

In this cohort study, 91% of patients with HFpEF had evidence of epicardial CAD, CMD, or both. Of those without obstructive CAD, 81% had CMD. Obstructive epicardial CAD and CMD appear to be common and often unrecognized in hospitalized patients with HFpEF and may be therapeutic targets.

Hydrogen gas inhalation ameliorates cardiac remodelling and fibrosis by regulating NLRP3 inflammasome in myocardial infarction rats

It is noteworthy that prolonged cardiac structural changes and excessive fibrosis caused by myocardial infarction (MI) seriously interfere with the treatment of heart failure in clinical practice. Currently, there are no effective and practical means of either prevention or treatment. Thus, novel therapeutic approaches are critical for the long‐term quality of life of individuals with myocardial ischaemia. Herein, we aimed to explore the protective effect of H₂, a novel gas signal molecule with anti‐oxidative stress and anti‐inflammatory effects, on cardiac remodelling and fibrosis in MI rats, and to explore its possible mechanism. First, we successfully established MI model rats, which were then exposed to H₂ inhalation with 2% concentration for 28 days (3 hours/day). The results showed that hydrogen gas can significantly improve cardiac function and reduce the area of cardiac fibrosis. In vitro experiments further proved that H₂ can reduce the hypoxia‐induced damage to cardiomyocytes and alleviate angiotensin II‐induced migration and activation of cardiac fibroblasts. In conclusion, herein, we illustrated for the first time that inhalation of H₂ ameliorates myocardial infarction‐induced cardiac remodelling and fibrosis in MI rats and exert its protective effect mainly through inhibiting NLRP3‐mediated pyroptosis.

Telmisartan ameliorates cardiac fibrosis and diastolic function in cardiorenal heart failure with preserved ejection fraction

Chronic kidney disease (CKD) is a major contributor to the development of heart failure with preserved ejection fraction (HFpEF), whereas the underlying mechanism of cardiorenal HFpEF is still elusive. The aim of this study was to investigate the role of cardiac fibrosis in a rat model of cardiorenal HFpEF and explore whether treatment with Telmisartan, an inhibitor of renin-angiotensin-aldosterone system (RAAS), can ameliorate cardiac fibrosis and preserve diastolic function in cardiorenal HFpEF. Male rats were subjected to 5/6 subtotal nephrectomy (SNX) or sham operation (Sham), and rats were allowed four weeks to recover and form a stable condition of CKD. Telmisartan or vehicle was then administered p.o. (8 mg/kg/d) for 12 weeks. Blood pressure, brain natriuretic peptide (BNP), echocardiography, and cardiac magnetic resonance imaging were acquired to evaluate cardiac structural and functional alterations. Histopathological staining, real-time polymerase chain reaction (PCR) and western blot were performed to evaluate cardiac remodeling. SNX rats showed an HFpEF phenotype with increased BNP, decreased early to late diastolic transmitral flow velocity (E/A) ratio, increased left ventricular (LV) hypertrophy and preserved ejection fraction (EF). Pathology revealed increased cardiac fibrosis in cardiorenal HFpEF rats compared with the Sham group, while chronic treatment with Telmisartan significantly decreased cardiac fibrosis, accompanied by reduced markers of fibrosis (collagen I and collagen III) and profibrotic cytokines (α-smooth muscle actin, transforming growth factor-β1, and connective tissue growth factor). In addition, myocardial inflammation was decreased after Telmisartan treatment, which was in a linear correlation with cardiac fibrosis. Telmisartan also reversed LV hypertrophy and E/A ratio, indicating that Telmisartan can improve LV remodeling and diastolic function in cardiorenal HFpEF. In conclusion, cardiac fibrosis is central to the pathology of cardiorenal HFpEF, and RAAS modulation with Telmisartan is capable of alleviating cardiac fibrosis and preserving diastolic dysfunction in this rat model.

The clinical and prognostic value of late Gadolinium enhancement imaging in heart failure with mid-range and preserved ejection fraction

Heart failure (HF) with mid-range or preserved ejection fraction (HFmrEF; HFpEF) is a heterogeneous disorder that could benefit from strategies to identify subpopulations at increased risk. We tested the hypothesis that HFmrEF and HFpEF patients with myocardial scars detected with late gadolinium enhancement (LGE) are at increased risk for all-cause mortality. Symptomatic HF patients with left ventricular ejection fraction (LVEF) > 40%, who underwent cardiac magnetic resonance (CMR) imaging were included. The presence of myocardial LGE lesions was visually assessed. T1 mapping was performed to calculate extracellular volume (ECV). Multivariable logistic regression analyses were used to determine associations between clinical characteristics and LGE. Cox regression analyses were used to assess the association between LGE and all-cause mortality. A total of 110 consecutive patients were included (mean age 71 ± 10 years, 49% women, median N-terminal brain natriuretic peptide (NT-proBNP) 1259 pg/ml). LGE lesions were detected in 37 (34%) patients. Previous myocardial infarction and increased LV mass index were strong and independent predictors for the presence of LGE (odds ratio 6.32, 95% confidence interval (CI) 2.07–19.31, p = 0.001 and 1.68 (1.03–2.73), p = 0.04, respectively). ECV was increased in patients with LGE lesions compared to those without (28.6 vs. 26.6%, p = 0.04). The presence of LGE lesions was associated with a fivefold increase in the incidence of all-cause mortality (hazards ratio 5.3, CI 1.5–18.1, p = 0.009), independent of age, sex, New York Heart Association (NYHA) functional class, NT-proBNP, LGE mass and LVEF. Myocardial scarring on CMR is associated with increased mortality in HF patients with LVEF > 40% and may aid in selecting a subpopulation at increased risk.

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

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

Heart failure with preserved ejection fraction based on aging and comorbidities

Heart failure (HF) with preserved ejection fraction (HFpEF) is a leading cause of hospitalizations and mortality when diagnosed at the age of ≥ 65 years. HFpEF represents multifactorial and multisystemic syndrome and has different pathophysiology and phenotypes. Its diagnosis is difficult to be established based on left ventricular ejection fraction and may benefit from individually tailored approaches, underlying age-related changes and frequent comorbidities. Compared with the rapid development in the treatment of heart failure with reduced ejection fraction, HFpEF presents a great challenge and needs to be addressed considering the failure of HF drugs to improve its outcomes. Further extensive studies on the relationships between HFpEF, aging, and comorbidities in carefully phenotyped HFpEF subgroups may help understand the biology, diagnosis, and treatment of HFpEF. The current review summarized the diagnostic and therapeutic development of HFpEF based on the complex relationships between aging, comorbidities, and HFpEF.

Signs of diastolic dysfunction are graded by serum testosterone levels in aging C57BL/6 male mice

We investigated whether maladaptive, age-associated changes in heart structure and function were linked to circulating testosterone levels. Male C57BL/6 mice had a gonadectomy (GDX) or sham surgery at 4 weeks and effects of GDX on the heart were examined with echocardiography. Serum testosterone was measured with ELISA. Left ventricular (LV) mass increased with age but was smaller in GDX mice than sham at 18 months (144.0 ± 8.7 vs 118.2 ± 11.9 mg; p = 0.009). The isovolumic relaxation time (IVRT) declined with age but was prolonged in GDX mice at 18 months (10.5 ± 0.8 vs 12.5 ± 0.5 msec, p = 0.008). Ejection fraction did not change with age or GDX, but E/A ratios were lower in GDX mice than controls at 18 months (1.6 ± 0.2 vs 1.3 ± 0.1, p = 0.021). When links between serum testosterone and cardiac parameters were examined longitudinally in 18-24-month-old mice, LV mass declined with decreasing testosterone (β = 37.70, p = 0.016), however IVRT increased as testosterone decreased (β=-2.69, p = 0.036). Since longer IVRT and lower E/A ratios are signs of diastolic dysfunction, low circulating testosterone may promote or exacerbate diastolic dysfunction in older males. These findings suggest that lower testosterone directly modifies heart structure and function to promote maladaptive remodeling and diastolic dysfunction in the aging heart.

Cellular and molecular pathobiology of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) affects half of all patients with heart failure worldwide, is increasing in prevalence, confers substantial morbidity and mortality, and has very few effective treatments. HFpEF is arguably the greatest unmet medical need in cardiovascular disease. Although HFpEF was initially considered to be a haemodynamic disorder characterized by hypertension, cardiac hypertrophy and diastolic dysfunction, the pandemics of obesity and diabetes mellitus have modified the HFpEF syndrome, which is now recognized to be a multisystem disorder involving the heart, lungs, kidneys, skeletal muscle, adipose tissue, vascular system, and immune and inflammatory signalling. This multiorgan involvement makes HFpEF difficult to model in experimental animals because the condition is not simply cardiac hypertrophy and hypertension with abnormal myocardial relaxation. However, new animal models involving both haemodynamic and metabolic disease, and increasing efforts to examine human pathophysiology, are revealing new signalling pathways and potential therapeutic targets. In this Review, we discuss the cellular and molecular pathobiology of HFpEF, with the major focus being on mechanisms relevant to the heart, because most research has focused on this organ. We also highlight the involvement of other important organ systems, including the lungs, kidneys and skeletal muscle, efforts to characterize patients with the use of systemic biomarkers, and ongoing therapeutic efforts. Our objective is to provide a roadmap of the signalling pathways and mechanisms of HFpEF that are being characterized and which might lead to more patient-specific therapies and improved clinical outcomes.

Integrating Measures of Myocardial Fibrosis in the Transition from Hypertensive Heart Disease to Heart Failure

PURPOSE OF REVIEW

This review aims to summarize recent developments in identifying and quantifying both the presence and amount of myocardial fibrosis by imaging and biomarkers. Further, this review seeks to describe in general ways how this information may be used to identify hypertension and the transition to heart failure with preserved ejection fraction.

RECENT FINDINGS

Recent studies using cardiac magnetic resonance imaging highlight the progressive nature of fibrosis from normal individuals to those with hypertension to those with clinical heart failure. However, separating hypertensive patients from those with heart failure remains challenging. Recent studies involving echocardiography show the subclinical myocardial strain changes between hypertensive heart disease and heart failure. Lastly, recent studies highlight the potential use of biomarkers to identify those with hypertension at the greatest risk of developing heart failure. In light of the heterogeneous nature between hypertension and heart failure with preserved ejection fraction, an integrated approach with cardiac imaging and biomarker analysis may enable clinicians and investigators to more accurately characterize, prevent, and treat heart failure in those with hypertension.

Plasma P-selectin is a predictor of mortality in heart failure with preserved ejection fraction

Aims

The aim of the study was to assess the association of P‐selectin with outcomes in heart failure with preserved ejection fraction (HFpEF).

Methods and results

This is a prospective, observational study of 130 HFpEF patients who underwent clinical profiling, blood sampling, 6 min walk testing, Minnesota Living with Heart Failure Questionnaire evaluation, echocardiography, cardiovascular magnetic resonance imaging, calculation of the Meta‐Analysis Global Group in Chronic Heart Failure (MAGGIC) risk scores, and blinded plasma P‐selectin measurement. Patients were followed up for the endpoint of all‐cause mortality. The HFpEF subgroup with higher P‐selectin levels [overall median 26 372, inter‐quartile range (19 360–34 889) pg/mL] was associated with lower age, higher heart rate, less prevalent atrial fibrillation, more frequent current smoking status, and lower right ventricular end‐diastolic volumes. During follow‐up (median 1428 days), there were 38 deaths. Following maximal sensitivity and specificity receiver operating characteristic curve analysis, P‐selectin levels above 35 506 pg/mL were associated with greater risk of all‐cause mortality [hazard ratio (HR) 2.700; 95% confidence interval (CI) 1.416–5.146; log‐rank P = 0.002]. Following multivariable Cox proportional hazards regression analysis and when added to MAGGIC scores, only P‐selectin (adjusted HR 1.707; 95% CI 1.099–2.650; P < 0.017) and myocardial infarction detected by cardiovascular magnetic resonance imaging (HR 2.377; 95% CI 1.114–5.075; P < 0.025) remained significant predictors. In a final model comprising all three parameters, only P‐selectin (HR 1.447; 95% CI 1.130–1.853; P < 0.003) and MAGGIC scores (HR 1.555; 95% CI 1.136–2.129; P < 0.006) remained independent predictors of death. Adding P‐selectin (0.618, P = 0.035) improved the area under the receiver operating characteristic curve for mortality prediction for MAGGIC scores (0.647, P = 0.009) to 0.710, P < 0.0001.

Conclusions

Plasma P‐selectin is an independent predictor of mortality and provides incremental prognostic information beyond MAGGIC scores in HFpEF.

Empagliflozin Reduces Myocardial Extracellular Volume in Patients With Type 2 Diabetes and Coronary Artery Disease

OBJECTIVES

This study sought to evaluate the effects of empagliflozin on extracellular volume (ECV) in individuals with type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD).

BACKGROUND

Empagliflozin has been shown to reduce left ventricular mass index (LVMi) in patients with T2DM and CAD. The effects on myocardial ECV are unknown.

METHODS

This was a prespecified substudy of the EMPA-HEART (Effects of Empagliflozin on Cardiac Structure in Patients with Type 2 Diabetes) CardioLink-6 trial in which 97 participants were randomized to receive empagliflozin 10 mg daily or placebo for 6 months. Data from 74 participants were included: 39 from the empagliflozin group and 35 from the placebo group. The main outcome was change in left ventricular ECV from baseline to 6 months determined by cardiac magnetic resonance (CMR). Other outcomes included change in LVMi, indexed intracellular compartment volume (iICV) and indexed extracellular compartment volume (iECV), and the fibrosis biomarkers soluble suppressor of tumorgenicity (sST2) and matrix metalloproteinase (MMP)-2.

RESULTS

Baseline ECV was elevated in the empagliflozin group (29.6 ± 4.6%) and placebo group (30.6 ± 4.8%). Six months of empagliflozin therapy reduced ECV compared with placebo (adjusted difference: -1.40%; 95% confidence interval [CI]: -2.60 to -0.14%; p = 0.03). Empagliflozin therapy reduced iECV (adjusted difference: -1.5 ml/m²; 95% CI: -2.6 to -0.5 ml/m²; p = 0.006), with a trend toward reduction in iICV (adjusted difference: -1.7 ml/m²; 95% CI: -3.8 to 0.3 ml/m²; p = 0.09). Empagliflozin had no impact on MMP-2 or sST2.

CONCLUSIONS

In individuals with T2DM and CAD, 6 months of empagliflozin reduced ECV, iECV, and LVMi. No changes in MMP-2 and sST2 were seen. Further investigation into the mechanisms by which empagliflozin causes reverse remodeling is required. (Effects of Empagliflozin on Cardiac Structure in Patients With Type 2 Diabetes [EMPA-HEART]; NCT02998970).

Left ventricular fibrosis and hypertrophy are associated with mortality in heart failure with preserved ejection fraction

Cardiac magnetic resonance (CMR) is emerging as an important tool in the assessment of heart failure with preserved ejection fraction (HFpEF). This study sought to investigate the prognostic value of multiparametric CMR, including left and right heart volumetric assessment, native T1-mapping and LGE in HFpEF. In this retrospective study, we identified patients with HFpEF who have undergone CMR. CMR protocol included: cines, native T1-mapping and late gadolinium enhancement (LGE). The mean follow-up period was 3.2 ± 2.4 years. We identified 86 patients with HFpEF who had CMR. Of the 86 patients (85% hypertensive; 61% males; 14% cardiac amyloidosis), 27 (31%) patients died during the follow up period. From all the CMR metrics, LV mass (area under curve [AUC] 0.66, SE 0.07, 95% CI 0.54-0.76, p = 0.02), LGE fibrosis (AUC 0.59, SE 0.15, 95% CI 0.41-0.75, p = 0.03) and native T1-values (AUC 0.76, SE 0.09, 95% CI 0.58-0.88, p < 0.01) were the strongest predictors of all-cause mortality. The optimum thresholds for these were: LV mass > 133.24 g (hazard ratio [HR] 1.58, 95% CI 1.1-2.2, p < 0.01); LGE-fibrosis > 34.86% (HR 1.77, 95% CI 1.1-2.8, p = 0.01) and native T1 > 1056.42 ms (HR 2.36, 95% CI 0.9-6.4, p = 0.07). In multivariate cox regression, CMR score model comprising these three variables independently predicted mortality in HFpEF when compared to NTproBNP (HR 4 vs HR 1.65). In non-amyloid HFpEF cases, only native T1 > 1056.42 ms demonstrated higher mortality (AUC 0.833, p < 0.01). In patients with HFpEF, multiparametric CMR aids prognostication. Our results show that left ventricular fibrosis and hypertrophy quantified by CMR are associated with all-cause mortality in patients with HFpEF.

Myocardial fibrosis, diastolic dysfunction and elevated liver stiffness in the Fontan circulation

Introduction

Single ventricle diastolic dysfunction and hepatic fibrosis are frequently observed in patients with a Fontan circulation. The relationship between adverse haemodynamics and end-organ fibrosis has not been investigated in adolescents and young adults with Fontan circulation.

Methods

Prospective observational study of Fontan patients who had a cardiac catheterisation. Cardiac MRI with T1 mapping was obtained to measure extracellular volume (ECV), a marker of myocardial fibrosis. Hepatic magnetic resonance elastography was performed to assess liver shear stiffness. Serum biomarkers of fibrosis including matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) were measured. Very high ECV was defined as >30% and elevated serum biomarkers as >75th percentile for each biomarker.

Results

25 Fontan patients (52% female) with mean age of 16.3±6.8 years were included. Mean ECV was 28%±5%. There was a significant correlation between ECV and systemic ventricular end-diastolic pressure (r=0.42, p=0.03) and between ECV and liver stiffness (r=0.45, p=0.05). Patients with elevated ECV demonstrated elevations in MMPs and TIMPs. Similarly, patients with elevated MMPs and TIMPs had greater liver stiffness compared with patients with normal levels of these biomarkers.

Conclusions

In Fontan patients, cardiac magnetic resonance evidence of myocardial fibrosis is associated with diastolic dysfunction, increased liver stiffness and elevated circulating biomarkers of fibrosis. These findings suggest the presence of a profibrotic milieu, with end-organ implications, in some patients with Fontan circulation.