Effects of loop diuretics on myocardial fibrosis and collagen type I turnover in chronic heart failure

Galectin-3 (Gal-3) and the tissue inhibitor of matrix metalloproteinase (TIMP-2) as potential biomarkers for the clinical evolution of chronic Chagas cardiomyopathy

BACKGROUND

Chronic Chagas cardiomyopathy (CCC) is responsible for the highest morbidity and worst prognosis in Chagas disease patients. However, predicting factors that correlate with disease progression, morbidity, and mortality is challenging. It is necessary to have simple, quantitative, and economical risk biomarkers that add value to conventional methods and assist in the diagnosis and prognosis of patients with CCC or in evolution.

OBJECTIVES

We evaluated molecules related to cardiac remodeling and fibrosis, such as MMP-2, MMP-9, TIMP-2, TIMP-1, PICP, CTXI, and Gal-3, and correlated these biomarkers with echocardiographic variables (LVDD, LVEF, and E/e' ratio).

METHODS

Blood samples from Chagasic patients without apparent cardiopathy (WAC), CCC patients, and healthy individuals were used to perform plasma molecule dosages using Luminex or ELISA.

RESULTS

MMP-2 and TIMP-2 presented higher levels in CCC; in these patients, the inhibitory role of TIMP-2 over MMP-2 was reinforced. The ratio of MMP-2/TIMP-2 in WAC patients showed a bias in favor of the gelatinase pathway. MMP-9 and TIMP-1 showed higher levels in Chagas patients compared to healthy subjects. PICP and CTXI are not associated with cardiac deterioration in Chagas disease. Increased levels of Gal-3 are associated with worse cardiac function in CCC. Receiver operating characteristic (ROC) curve analysis identified Gal-3 and TIMP-2 as putative biomarkers to discriminate WAC from cardiac patients.

CONCLUSIONS

Among the molecules evaluated, Gal-3 and TIMP-2 have the potential to be used as biomarkers of cardiac remodeling and progressive myocardial fibrosis in Chagas disease.

Myocardial Interstitial Fibrosis in Hypertensive Heart Disease: From Mechanisms to Clinical Management

Hypertensive heart disease (HHD) can no longer be considered as the beneficial adaptive result of the hypertrophy of cardiomyocytes in response to pressure overload leading to the development of left ventricular hypertrophy. The current evidence indicates that in patients with HHD, pathological lesions in the myocardium lead to maladaptive structural remodeling and subsequent alterations in cardiac function, electrical activity, and perfusion, all contributing to poor outcomes. Diffuse myocardial interstitial fibrosis is probably the most critically involved lesion in these disorders. Therefore, in this review, we will focus on the histological characteristics, the mechanisms, and the clinical consequences of myocardial interstitial fibrosis in patients with HHD. In addition, we will consider the most useful tools for the noninvasive diagnosis of myocardial interstitial fibrosis in patients with HHD, as well as the most effective available therapeutic strategies to prevent its development or facilitate its regression in this patient population. Finally, we will issue a call to action for the need for more fundamental and clinical research on myocardial interstitial fibrosis in HHD.

Effect of Furosemide Versus Torsemide on Hospitalizations and Mortality in Patients With Heart Failure: A Meta-Analysis of Randomized Controlled Trials

Loop diuretics are essential in the treatment of patients with heart failure (HF) who develop congestion. Furosemide is the most commonly used diuretic; however, some randomized controlled trials (RCTs) have shown varying results associated with torsemide and furosemide in terms of hospitalizations and mortality. We performed an updated meta-analysis of currently available RCTs comparing furosemide and torsemide to see if there is any difference in clinical outcomes in patients treated with these loop diuretics. PubMed, MEDLINE, Cochrane, and Embase databases were searched for RCTs comparing the outcomes in patients with HF treated with furosemide versus torsemide. The primary end points included all-cause mortality, all-cause hospitalizations, cardiovascular-related hospitalizations, and HF-related hospitalizations. A random-effects meta-analysis was performed to estimate the risk ratio (RR) with a 95% confidence interval (CI). A total of 10 RCTs with 4,127 patients (2,088 in the furosemide group and 2,039 in the torsemide group) were included in this analysis. A total of 56% of the patients were men and the mean age was 68 years. No significant difference was noted in all-cause mortality between the furosemide and torsemide groups (RR 1.02, 95% CI 0.91 to 1.15, p = 0.70); however, patients treated with furosemide compared with torsemide had higher risks of cardiovascular hospitalizations (RR 1.36, 95% CI 1.13 to 1.65, p = 0.001), HF-related hospitalizations (RR 1.65, 95% CI 1.21 to 2.24, p = 0.001), and all-cause hospitalizations (RR 1.06, 95% CI 1.01 to 1.11, p = 0.02). In conclusion, patients with HF treated with torsemide have a reduced risk of hospitalizations compared with those treated with furosemide, without any difference in mortality. These data indicate that torsemide may be a better choice to treat patients with HF.

Clinical Outcomes With Furosemide Versus Torsemide in Patients With Heart Failure: An Updated Systematic Review and Meta-Analysis

Despite potential advantages of torsemide over furosemide, <10% of the patients with heart failure (HF) are on torsemide in clinical practice. Prior studies comparing furosemide to torsemide in patients with HF have shown conflicting findings, regarding hospitalizations and mortality. We aimed to pool all the studies conducted to date and provide the most updated and comprehensive evidence, regarding the effect of furosemide vs torsemide in reducing mortality and hospitalizations in patients with HF. We conducted a comprehensive literature search of the PubMed/Medline, Cochrane Library and Scopus from inception till June 2023, for randomized and nonrandomized studies comparing furosemide to torsemide in adult patients (>18 years) with acute or chronic HF. Data about all-cause mortality, HF-related hospitalizations and all-cause hospitalizations was extracted, pooled, and analyzed. Forest plots were created based on the random effects model. A total of 17 studies (n = 11,996 patients) were included in our analysis with a median follow-up time of 8 months. Our pooled analysis demonstrated no difference in all-cause mortality between furosemide and torsemide groups in HF patients (OR = 0.98, 95% CI: 0.75-1.29, P = 0.89). However, torsemide was associated with a significantly lesser incidence of HF-related hospitalizations (OR = 0.73, 95% CI: 0.54-0.99, P = 0.04), and all-cause hospitalizations (OR = 0.84, 95% CI: 0.73-0.98, P = 0.03), as compared to furosemide. Torsemide significantly reduces HF-related and all-cause hospitalizations as compared to furosemide, with no difference in mortality. We recommend transitioning from furosemide to torsemide in HF patients who are not attaining symptomatic control.

Dual-Energy Computed Tomography in Cardiac Imaging

Dual-energy computed tomography (DECT) acquires images using two energy spectra and offers a variation of reconstruction techniques for improved cardiac imaging. Virtual monoenergetic images decrease artifacts improving coronary plaque and stent visualization. Further, contrast attenuation is increased allowing significant reduction of contrast dose. Virtual non-contrast reconstructions enable coronary artery calcium scoring from contrast-enhanced scans. DECT provides advanced plaque imaging with detailed analysis of plaque components, indicating plaque stability. Extracellular volume assessment using DECT offers noninvasive detection of myocardial fibrosis. This review aims to outline the current cardiac applications of DECT, summarize recent literature, and discuss their findings.

Cardiac Fibrosis in heart failure: Focus on non-invasive diagnosis and emerging therapeutic strategies

Heart failure is a leading cause of mortality and hospitalization worldwide. Cardiac fibrosis, resulting from the excessive deposition of collagen fibers, is a common feature across the spectrum of conditions converging in heart failure. Eventually, either reparative or reactive in nature, in the long-term cardiac fibrosis contributes to heart failure development and progression and is associated with poor clinical outcomes. Despite this, specific cardiac antifibrotic therapies are lacking, making cardiac fibrosis an urgent unmet medical need. In this context, a better patient phenotyping is needed to characterize the heterogenous features of cardiac fibrosis to advance toward its personalized management. In this review, we will describe the different phenotypes associated with cardiac fibrosis in heart failure and we will focus on the potential usefulness of imaging techniques and circulating biomarkers for the non-invasive characterization and phenotyping of this condition and for tracking its clinical impact. We will also recapitulate the cardiac antifibrotic effects of existing heart failure and non-heart failure drugs and we will discuss potential strategies under preclinical development targeting the activation of cardiac fibroblasts at different levels, as well as targeting additional extracardiac processes.

Drugs for treating myocardial fibrosis

Myocardial fibrosis, which is a common pathological manifestation of many cardiovascular diseases, is characterized by excessive proliferation, collagen deposition and abnormal distribution of extracellular matrix fibroblasts. In clinical practice, modern medicines, such as diuretic and β receptor blockers, and traditional Chinese medicines, such as salvia miltiorrhiza and safflower extract, have certain therapeutic effects on myocardial fibrosis. We reviewed some representative modern medicines and traditional Chinese medicines (TCMs) and their related molecular mechanisms for the treatment of myocardial fibrosis. These drugs alleviate myocardial fibrosis by affecting related signaling pathways and inhibiting myocardial fibrosis-related protein synthesis. This review will provide more references and help for the research and treatment of myocardial fibrosis.

Sacubitril/valsartan versus valsartan in regressing myocardial fibrosis in hypertension: a prospective, randomized, open-label, blinded endpoint clinical trial protocol

Background

Diffuse interstitial myocardial fibrosis is a key common pathological manifestation in hypertensive heart disease (HHD) progressing to heart failure (HF). Angiotensin receptor-neprilysin inhibitors (ARNi), now a front-line treatment for HF, confer benefits independent of blood pressure, signifying a multifactorial mode of action beyond hemodynamic regulation. We aim to test the hypothesis that compared with angiotensin II receptor blockade (ARB) alone, ARNi is more effective in regressing diffuse interstitial myocardial fibrosis in HHD.

Methods

Role of ARNi in Ventricular Remodeling in Hypertensive LVH (REVERSE-LVH) is a prospective, randomized, open-label, blinded endpoint (PROBE) clinical trial. Adults with hypertension and left ventricular hypertrophy (LVH) according to Asian sex- and age-specific thresholds on cardiovascular magnetic resonance (CMR) imaging are randomized to treatment with either sacubitril/valsartan (an ARNi) or valsartan (an ARB) in 1:1 ratio for a duration of 52 weeks, at the end of which a repeat CMR is performed to assess differential changes from baseline between the two groups. The primary endpoint is the change in CMR-derived diffuse interstitial fibrosis volume. Secondary endpoints include changes in CMR-derived left ventricular mass, volumes, and functional parameters. Serum samples are collected and stored to assess the effects of ARNi, compared with ARB, on circulating biomarkers of cardiac remodeling. The endpoints will be analyzed with reference to the corresponding baseline parameters to evaluate the therapeutic effect of sacubitril/valsartan vs. valsartan.

Discussion

REVERSE-LVH will examine the anti-fibrotic potential of sacubitril/valsartan and will offer mechanistic insights into the clinical benefits of sacubitril/valsartan in hypertension in relation to cardiac remodeling. Advancing the knowledge of the pathophysiology of HHD will consolidate effective risk stratification and personalized treatment through a multimodal manner integrating complementary CMR and biomarkers into the conventional care approach.Clinical Trial Registration: ClinicalTrials.gov, identifier, NCT03553810.

The Potential Role of Torsemide in Optimizing Loop Diuretic Therapy for Heart Failure Patients

Heart failure is associated with an increased frequency of hospitalization, reduced life span, and greater risk to public health, thus posing a challenge. In India, torsemide is one of the commonly used loop diuretics for decongestion in heart failure. However, this use of torsemide, including its dosing, and up/down titration, is based on practical experience. Loop diuretic therapy for heart failure patients poses several dilemmas due to the lack of robust evidence based on which treatment decisions can be made. To guide physicians on the optimal use of torsemide in heart failure patients with or without renal impairment, a panel of expert cardiologists and nephrologists from India convened to develop this expert opinion document for the use of torsemide. This expert opinion on torsemide will pave the way for optimal management with loop diuretic therapy in real-world heart failure patients.

Identification of Gene Expression Signatures for Phenotype-Specific Drug Targeting of Cardiac Fibrosis

We have designed translational animal models to investigate cardiac profibrotic gene signatures. Domestic pigs were treated with cardiotoxic drugs (doxorubicin, DOX, n = 5 or Myocet^®, MYO, n = 5) to induce replacement fibrosis via cardiotoxicity. Reactive interstitial fibrosis was triggered by LV pressure overload by artificial isthmus stenosis with stepwise developing myocardial hypertrophy and final fibrosis (Hyper, n = 3) or by LV volume overload in the adverse remodeled LV after myocardial infarction (RemoLV, n = 3). Sham interventions served as controls and healthy animals (Control, n = 3) served as a reference in sequencing study. Myocardial samples from the LV of each group were subjected to RNA sequencing. RNA-seq analysis revealed a clear distinction between the transcriptomes of myocardial fibrosis (MF) models. Cardiotoxic drugs activated the TNF-alpha and adrenergic signaling pathways. Pressure or volume overload led to the activation of FoxO pathway. Significant upregulation of pathway components enabled the identification of potential drug candidates used for the treatment of heart failure, such as ACE inhibitors, ARB, ß-blockers, statins and diuretics specific to the distinct MF models. We identified candidate drugs in the groups of channel blockers, thiostrepton that targets the FOXM1-regulated ACE conversion to ACE2, tyrosine kinases or peroxisome proliferator-activated receptor inhibitors. Our study identified different gene targets involved in the development of distinct preclinical MF protocols enabling tailoring expression signature-based approach for the treatment of MF.

Circulating Biomarkers of Fibrosis Formation in Patients with Arrhythmogenic Cardiomyopathy

Arrhythmogenic cardiomyopathy (ACM) is a progressive inheritable disease which is characterized by a gradual fibro-(fatty) replacement of the myocardium. Visualization of diffuse and patchy fibrosis patterns is challenging using clinically applied cardiac imaging modalities (e.g., late gadolinium enhancement, LGE). During collagen synthesis and breakdown, carboxy–peptides are released into the bloodstream, specifically procollagen type-I carboxy-terminal propeptides (PICP) and collagen type-I carboxy-terminal telopeptides (ICTP). We collected the serum and EDTA blood samples and clinical data of 45 ACM patients (age 50.11 ± 15.53 years, 44% female), divided into 35 diagnosed ACM patients with a 2010 ARVC Task Force Criteria score (TFC) ≥ 4, and 10 preclinical variant carriers with a TFC < 4. PICP levels were measured using an enzyme-linked immune sorbent assay and ICTP levels with a radio immunoassay. Increased PICP/ICTP ratios suggest a higher collagen deposition. We found significantly higher PICP and PICP/ICTP levels in diagnosed patients compared to preclinical variant carriers (p < 0.036 and p < 0.027). A moderate negative correlation existed between right ventricular ejection fractions (RVEF) and the PICP/ICTP ratio (r = −0.46, p = 0.06). In addition, significant correlations with left ventricular function (LVEF r = −0.53, p = 0.03 and end-systolic volume r = 0.63, p = 0.02) were found. These findings indicate impaired contractile performance due to pro-fibrotic remodeling. Follow-up studies including a larger number of patients should be performed to substantiate our findings and the validity of those levels as potential promising biomarkers in ACM.

Growing Heart Failure Burden of Hypertensive Heart Disease: A Call to Action

Hypertensive heart disease (HHD) is currently the second leading cause of heart failure. The prevalence of HHD and its associated risk of heart failure have increased despite substantial improvement in arterial hypertension treatment and control in the recent decades. Therefore, the prevention of heart failure in patients with HHD represents an unmet medical need, due to its clinical, economic, and social impact. In this conceptual framework, we call to action because the time has come for diagnosis and treatment of patients with HHD not to be limited to assessment of morphological and functional left ventricular changes, blood pressure control, and left ventricular hypertrophy regression. We propose a further perspective incorporating also the detection and reversal of the histological changes that develop in the hypertensive heart and that lead to the structural remodeling of the myocardium. In particular, we focus on the diagnosis and treatment of myocardial interstitial fibrosis, likely the lesion most critically involved in the transition from subclinical HHD to clinically overt heart failure. In this context, it is worth considering whether the use of imaging and circulating biomarkers for the noninvasive diagnosis of myocardial interstitial fibrosis should be incorporated in the medical study of hypertensive patients, especially of those with HHD.

Salvia miltiorrhiza in thorax and abdomainal organ fibrosis: A review of its pharmacology

Organ fibrosis is a common pathological change that finally results in organ failure, which involves the destruction of parenchyma cells, the activation of mesenchymal cells and the imbalance of immunological cells. In recent years, although some breakthroughs have been made in understanding the pathogenesis and therapeutics of organ fibrosis, no registered drugs could directly target the fibrotic process, which constitutes a major biomedical challenge. Salvia miltiorrhiza (SM) is a well-known medicinal plant in China, which has been widely applied because of its pharmacological effects on anti-oxidative, anti-myocardial infarction, anti-fibrotic, anti-inflammatory, and anti-neoplastic properties. Accumulated evidence suggested that SM played critical roles against organ fibrosis in vivo and in vitro experiments by its multiple biological compounds. In this review, we discussed the recent advances on the phytochemistry and pharmacological mechanisms of SM and its active ingredients in liver, lung, kidney, and heart fibrosis, which might help to promote the treatment of fibrotic diseases in thorax and abdomainal viscera in clinic.

Use of short-acting vs. long-acting loop diuretics after heart failure hospitalization

AIMS

Furosemide, a short-acting loop diuretic (SD), is the dominant agent prescribed for heart failure (HF) in clinical practice. However, accumulating data suggests that long-acting loop diuretics (LD), such as torsemide or azosemide, might have more favourable pharmacological profiles. This study aimed to investigate the relationship between the type of loop diuretics and long-term outcomes among patients hospitalized for acute HF enrolled in a contemporary multicentre registry.

METHODS AND RESULTS

Within the West Tokyo Heart Failure Registry from 2006 to 2017, a total of 2680 patients (60.1% men with a median age of 77 years) were analysed. The patients were characterized by the type of diuretics used at the time of discharge; 2073 (77.4%) used SD, and 607 (22.6%) used LD. The primary endpoint was composite of all-cause death or HF re-admission after discharge, and the secondary endpoints were all-cause death and HF re-admission, respectively. During the median follow-up period of 2.1 years, 639 patients died [n = 519 (25.0%) in the SD group; n = 120 (19.8%) in the LD group], and 868 patients were readmitted for HF [n = 697 (33.6%) in the SD group; n = 171 (28.2%) in the LD group]. After multivariable adjustment, the LD group had lower risk for the composite outcome [hazard ratio (HR), 0.80; 95% confidence interval (CI), 0.66-0.96; P = 0.017], including all-cause death (HR; 0.73; 95% CI; 0.54-0.99; P = 0.044) and HF re-admission (HR, 0.81; 95% CI, 0.66-0.99; P = 0.038), than the SD group. Propensity score matching yielded estimates that were consistent with those of the multivariable analyses, with sub-group analyses demonstrating that use of LD was associated with favourable outcomes predominantly in younger patients with reduced ejection fraction.

CONCLUSIONS

LD was associated with lower risk of long-term outcomes in patients with HF and a recent episode of acute decompensation.

The association between markers of type I collagen synthesis and echocardiographic response to spironolactone in patients at risk of heart failure: findings from the HOMAGE trial

BACKGROUND

Procollagen type I C-terminal propeptide (PICP) and procollagen type III N-terminal propeptide (PIIINP) are markers reflecting collagen synthesis in cardiac fibrosis. However, they may be influenced by the presence of noncardiac comorbidities (e.g., ageing, obesity, renal impairment). Understanding the associations between markers of collagen synthesis and abnormalities of cardiac structure and function is important to screen for myocardial fibrosis and monitor the antifibrotic effect of medications.

METHODS

The HOMAGE (Heart OMics in Aging) trial showed that spironolactone decreased serum PICP concentrations and improved cardiac remodeling over 9 months in a population at risk of developing heart failure (HF). We evaluated the associations between echocardiographic variables, PICP, PIIINP and galectin-3 at baseline and during the course of the trial.

RESULTS

Among 527 individuals (74±7years, 26% women), median serum concentrations of PICP, PIIINP and galectin-3 were 80.6μg/L (65.1-97.0), 3.9μg/L (3.1-5.0) and 16.1μg/L (13.5-19.7), respectively. After adjustment for potential confounders, higher serum PICP was significantly associated with left ventricular hypertrophy, left atrial enlargement, and greater ventricular stiffness (all p-values<0.05), whereas serum PIIINP and galectin-3 were not (all p-values>0.05). In patients treated with spironolactone, a reduction in serum PICP during the trial was associated with a decrease in E/e' (adjusted-beta [95% CI] =0.93 [0.14-1.73]; p=0.022).

CONCLUSIONS

In individuals at high risk of developing HF, serum PICP was associated with cardiac structural and functional abnormalities, and a decrease in PICP with spironolactone was correlated with improved diastolic dysfunction as assessed by E/e'. In contrast, no such associations were present for serum PIIINP and galectin-3.

Ongoing Clinical Trials in Aging-Related Tissue Fibrosis and New Findings Related to AhR Pathways

Fibrosis is a pathological manifestation of wound healing that replaces dead/damaged tissue with collagen-rich scar tissue to maintain homeostasis, and complications from fibrosis contribute to nearly half of all deaths in the industrialized world. Ageing is closely associated with a progressive decline in organ function, and the prevalence of tissue fibrosis dramatically increases with age. Despite the heavy clinical and economic burden of organ fibrosis as the population ages, to date, there is a paucity of therapeutic strategies that are specifically designed to slow fibrosis. Aryl hydrocarbon receptor (AhR) is an environment-sensing transcription factor that exacerbates aging phenotypes in different tissues that has been brought back into the spotlight again with economic development since AhR could interact with persistent organic pollutants derived from incomplete waste combustion. In addition, gut microbiota dysbiosis plays a pivotal role in the pathogenesis of numerous diseases, and microbiota-associated tryptophan metabolites are dedicated contributors to fibrogenesis by acting as AhR ligands. Therefore, a better understanding of the effects of tryptophan metabolites on fibrosis modulation through AhR may facilitate the exploitation of new therapeutic avenues for patients with organ fibrosis. In this review, we primarily focus on how tryptophan-derived metabolites are involved in renal fibrosis, idiopathic pulmonary fibrosis, hepatic fibrosis and cardiac fibrosis. Moreover, a series of ongoing clinical trials are highlighted.

Cardiac remodelling - Part 1: From cells and tissues to circulating biomarkers. A review from the Study Group on Biomarkers of the Heart Failure Association of the European Society of Cardiology

Cardiac remodelling refers to changes in left ventricular structure and function over time, with a progressive deterioration that may lead to heart failure (HF) development (adverse remodelling) or vice versa a recovery (reverse remodelling) in response to HF treatment. Adverse remodelling predicts a worse outcome, whilst reverse remodelling predicts a better prognosis. The geometry, systolic and diastolic function and electric activity of the left ventricle are affected, as well as the left atrium and on the long term even right heart chambers. At a cellular and molecular level, remodelling involves all components of cardiac tissue: cardiomyocytes, fibroblasts, endothelial cells and leucocytes. The molecular, cellular and histological signatures of remodelling may differ according to the cause and severity of cardiac damage, and clearly to the global trend toward worsening or recovery. These processes cannot be routinely evaluated through endomyocardial biopsies, but may be reflected by circulating levels of several biomarkers. Different classes of biomarkers (e.g. proteins, non-coding RNAs, metabolites and/or epigenetic modifications) and several biomarkers of each class might inform on some aspects on HF development, progression and long-term outcomes, but most have failed to enter clinical practice. This may be due to the biological complexity of remodelling, so that no single biomarker could provide great insight on remodelling when assessed alone. Another possible reason is a still incomplete understanding of the role of biomarkers in the pathophysiology of cardiac remodelling. Such role will be investigated in the first part of this review paper on biomarkers of cardiac remodelling.

Effects of Sacubitril/Valsartan on biomarkers of fibrosis and inflammation in patients with heart failure with reduced ejection fraction

AIMS

To evaluate the circulating levels of remodeling biomarkers procollagen type 1 C-terminal propeptide (PICP), human cartilage glycoprotein-39 (YKL-40), plasma renin activity (PRA), aldosterone (Aldo) as well as clinical and echocardiographic parameters in patients with heart failure with reduced ejection fraction (HFrEF), before and after treatment with Sacubitril/Valsartan (S/V).

METHODS AND RESULTS

A total of 26 consecutive patients with HFrEF on stable clinical conditions were studied. Clinical, echocardiographic parameters and circulating biomarkers were measured at baseline, after 30 and 60 days of S/V treatment. Both systolic blood pressure (SBP) and diastolic blood pressure (DBP) decreased, from 126 ± 15 to 113 ± 4 mmHg (p < 0.001) and from 77 ± 11 to 72 ± 9 mmHg (p = 0.005), respectively, at the end of study. Concomitantly, left ventricular ejection fraction (LVEF) increased by 22.8% from 29.5 ± 5% to 36.2 ± 5%, (p < 0.001) and indexed left ventricular end-systolic volume (LVESVi) decreased by 12% from 38.6 ± 8.7 ml/m² to 34.0 ± 10.0 ml/m². (p = 0.007). Circulating levels of PICP, YKL-40, PRA and Aldo decreased by - 42.2%, - 46.8%, - 79.1% and - 76.7%, respectively (p < 0.001 for all), the decrements being already maximal within 30 days of S/V treatment. No significant changes of plasma electrolytes and creatinine were observed during the study (all p > 0.05).

CONCLUSIONS

A decrease of circulating markers of inflammation and fibrosis during chronic treatment with S/V is associated with an improvement of hemodynamic and echographic parameters in patients with HRrEF. These data are compatible with an anti-fibrotic and anti-inflammatory effect of S/V, that may contribute to the beneficial outcomes of the drug in this clinical setting.

Cardiac Fibrosis in the Pressure Overloaded Left and Right Ventricle as a Therapeutic Target

Myocardial fibrosis is a remodeling process of the extracellular matrix (ECM) following cardiac stress. "Replacement fibrosis" is a term used to describe wound healing in the acute phase of an injury, such as myocardial infarction. In striking contrast, ECM remodeling following chronic pressure overload insidiously develops over time as "reactive fibrosis" leading to diffuse interstitial and perivascular collagen deposition that continuously perturbs the function of the left (L) or the right ventricle (RV). Examples for pressure-overload conditions resulting in reactive fibrosis in the LV are systemic hypertension or aortic stenosis, whereas pulmonary arterial hypertension (PAH) or congenital heart disease with right sided obstructive lesions such as pulmonary stenosis result in RV reactive fibrosis. In-depth phenotyping of cardiac fibrosis has made it increasingly clear that both forms, replacement and reactive fibrosis co-exist in various etiologies of heart failure. While the role of fibrosis in the pathogenesis of RV heart failure needs further assessment, reactive fibrosis in the LV is a pathological hallmark of adverse cardiac remodeling that is correlated with or potentially might even drive both development and progression of heart failure (HF). Further, LV reactive fibrosis predicts adverse outcome in various myocardial diseases and contributes to arrhythmias. The ability to effectively block pathological ECM remodeling of the LV is therefore an important medical need. At a cellular level, the cardiac fibroblast takes center stage in reactive fibrotic remodeling of the heart. Activation and proliferation of endogenous fibroblast populations are the major source of synthesis, secretion, and deposition of collagens in response to a variety of stimuli. Enzymes residing in the ECM are responsible for collagen maturation and cross-linking. Highly cross-linked type I collagen stiffens the ventricles and predominates over more elastic type III collagen in pressure-overloaded conditions. Research has attempted to identify pro-fibrotic drivers causing fibrotic remodeling. Single key factors such as Transforming Growth Factor β (TGFβ) have been described and subsequently targeted to test their usefulness in inhibiting fibrosis in cultured fibroblasts of the ventricles, and in animal models of cardiac fibrosis. More recently, modulation of phenotypic behaviors like inhibition of proliferating fibroblasts has emerged as a strategy to reduce pathogenic cardiac fibroblast numbers in the heart. Some studies targeting LV reactive fibrosis as outlined above have successfully led to improvements of cardiac structure and function in relevant animal models. For the RV, fibrosis research is needed to better understand the evolution and roles of fibrosis in RV failure. RV fibrosis is seen as an integral part of RV remodeling and presents at varying degrees in patients with PAH and animal models replicating the disease of RV afterload. The extent to which ECM remodeling impacts RV function and thus patient survival is less clear. In this review, we describe differences as well as common characteristics and key players in ECM remodeling of the LV vs. the RV in response to pressure overload. We review pre-clinical studies assessing the effect of anti-fibrotic drug candidates on LV and RV function and their premise for clinical testing. Finally, we discuss the mode of action, safety and efficacy of anti-fibrotic drugs currently tested for the treatment of left HF in clinical trials, which might guide development of new approaches to target right heart failure. We touch upon important considerations and knowledge gaps to be addressed for future clinical testing of anti-fibrotic cardiac therapies.

Extracellular Matrix in Heart Disease: Focus on Circulating Collagen Type I and III Derived Peptides as Biomarkers of Myocardial Fibrosis and Their Potential in the Prognosis of Heart Failure: A Concise Review

Accumulating evidence indicates that two major proteins are responsible for the structural coherence of bounding cardiomyocytes. These biomolecules are known as myocardial fibrillar collagen type I (COL1) and type III (COL3). In addition, fibronectin, laminin, fibrillin, elastin, glycoproteins, and proteoglycans take part in the formation of cardiac extracellular matrix (ECM). In physiological conditions, collagen synthesis and degradation in human cardiac ECM are well-regulated processes, but they can be impaired in certain cardiovascular diseases, such as heart failure (HF). Myocardial remodeling is part of the central mechanism of HF and involves cardiomyocyte injury and cardiac fibrosis due to increased fibrillar collagen accumulation. COL1 and COL3 are predominantly involved in this process. Specific products identified as collagen-derived peptides are released in the circulation as a result of abnormal COL1 and COL3 turnover and myocardial remodeling in HF and can be detected in patients' sera. The role of these products in the pathogenesis of cardiac fibrosis and the possible clinical implications are the focus of numerous investigations. This paper reviews recent studies on COL1- and COL3-derived peptides in patients with HF. Their potential application as indicators of myocardial fibrosis and prognostic markers of HF is also highlighted.

Gut Microbiome and Organ Fibrosis

Fibrosis is a pathological process associated with most chronic inflammatory diseases. It is defined by an excessive deposition of extracellular matrix proteins and can affect nearly every tissue and organ system in the body. Fibroproliferative diseases, such as intestinal fibrosis, liver cirrhosis, progressive kidney disease and cardiovascular disease, often lead to severe organ damage and are a leading cause of morbidity and mortality worldwide, for which there are currently no effective therapies available. In the past decade, a growing body of evidence has highlighted the gut microbiome as a major player in the regulation of the innate and adaptive immune system, with severe implications in the pathogenesis of multiple immune-mediated disorders. Gut microbiota dysbiosis has been associated with the development and progression of fibrotic processes in various organs and is predicted to be a potential therapeutic target for fibrosis management. In this review we summarize the state of the art concerning the crosstalk between intestinal microbiota and organ fibrosis, address the relevance of diet in different fibrotic diseases and discuss gut microbiome-targeted therapeutic approaches that are current being explored.

Proteomic differences among patients with heart failure taking furosemide or torsemide

BACKGROUND

Loop diuretics are commonly used for patients with heart failure (HF) but it remains unknown if one loop diuretic is clinically superior.

HYPOTHESIS

Biomarkers and proteomics provide insight to how different loop diuretics may differentially affect outcomes.

METHODS

Blood and urine were collected from outpatients with HF who were taking torsemide or furosemide for >30 days. Differences were assessed in cardiac, renal, and inflammatory biomarkers and soluble protein panels using the Olink Cardiovascular III and inflammation panels.

RESULTS

Of 78 subjects, 55 (71%) were treated with furosemide and 23 (29%) with torsemide, and 25 provided a urine sample (15 treated with furosemide, 10 with torsemide). Patients taking torsemide were older (68 vs 64 years) with a lower mean eGFR (46 vs 54 ml/min/1.73 m² ), a higher proportion were women (39% vs 24%) and Black (43% vs 27%). In plasma, levels of hs-cTnT, NT-proBNP, and hsCRP were not significantly different between groups. In urine, there were significant differences in urinary albumin, β-2M, and NGAL, with higher levels in the torsemide-treated patients. Of 184 proteins testing in Olink panels, in plasma, 156 (85%) were higher in patients taking torsemide but none were significantly different after correcting for false discovery.

CONCLUSIONS

We show differences in urinary biomarkers but few differences in plasma biomarkers among HF patients on different loop diuretics. Olink technology can detect differences in plasma protein levels from multiple biologic domains. These findings raise the importance of defining differences in mechanisms of action of each diuretic in an appropriately powered study.

Empagliflozin reduces diffuse myocardial fibrosis by extracellular volume mapping: A meta-analysis of clinical studies

OBJECTIVE

The aim of the study was to evaluate the effect of empagliflozin on diffuse myocardial fibrosis by cardiac magnetic resonance (CMR) T1 mapping.

RESEARCH METHODS AND PROCEDURES

Databases including PubMed, Cochrane library, Embase, and Sinomed for clinical studies of empagliflozin on myocardial fibrosis were searched. Two authors extracted the data and evaluated study quality independently. Weighted mean difference (WMD) and 95% confidence intervals (CI) were used for continuous variables. Review Manager 5.3 was used to performed the analysis.

RESULTS

Six studies were included in this meta-analysis. One of the six studies was assessed as poor quality by the assessment of methodological quality; however, the remaining five studies were considered good. The WMD value of △extracellular volume (ECV) was merged by the fixed-effect model, and the pooled effect size was -1.48 (95% CI -1.76 to -1.21, P < 0.00001), which means in favor of empagliflozin. Heterogeneity analysis did not find any heterogeneity (chi² = 0.39, P = 0.82, I ² = 0%). In addition, empagliflozin had a tendency to reduce ECV compared to treatment before with no statistical significance (WMD = -0.29, 95% CI -1.26 to 0.67, P = 0.55; heterozygosity test, chi² = 2.66, P = 0.45, I ² = 0%). The WMD value of △native T1 was also merged by the fixed-effect model, but the pooled effect size showed neither statistical difference between empagliflozin and placebo treatment (WMD = -5.40, 95% CI -21.63 to 10.83, P = 0.51) nor heterogeneity (chi² = 0.05, P = 0.83, I ² = 0%).

CONCLUSIONS

Empagliflozin has cardiovascular benefits by reducing diffuse myocardial fibrosis. ECV could act as a non-invasive imaging tool to assess diffuse myocardial fibrosis and monitor disease progression.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=324804, identifier: CRD42022324804.

Myocardial fibrosis in congenital heart disease

Myocardial fibrosis resulting from the excessive deposition of collagen fibers through the myocardium is a common histopathologic finding in a wide range of cardiovascular diseases, including congenital anomalies. Interstitial fibrosis has been identified as a major cause of myocardial dysfunction since it distorts the normal architecture of the myocardium and impairs the biological function and properties of the interstitium. This review summarizes current knowledge on the mechanisms and detrimental consequences of myocardial fibrosis in heart failure and arrhythmias, discusses the usefulness of available imaging techniques and circulating biomarkers to assess this entity and reviews the current body of evidence regarding myocardial fibrosis in the different subsets of congenital heart diseases with implications in research and treatment.

An evaluation of torsemide in patients with heart failure and renal disease

INTRODUCTION

Torsemide is a loop diuretic that inhibits the Na+/K+/2Cl- cotransporter type 2 in the thick ascending loop of Henle, leading to increased excretion of urinary sodium and chloride and associated diuresis. While furosemide remains the dominant diuretic utilized in current practice, increasing evidence supports potential advantages of torsemide in heart failure (HF) and/or renal disease.

AREAS COVERED

This narrative review covers the evidence for use of torsemide in HF and renal disease. Comparative effectiveness with regards to clinical outcomes is reviewed, as well as the ongoing multicenter trial, TRANSFORM-HF, comparing the effect of torsemide versus furosemide among patients with HF.

EXPERT OPINION

Compared with furosemide, torsemide has favorable pharmacodynamics/pharmacokinetics including higher bioavailability, longer duration of effect, minor renal excretion, decreased kaliuresis, and enhanced natriuresis/diuresis. These properties may be further supported by differential effects on RAAS regulation and fibrosis modulation as compared with other diuretics. The limited current body of evidence indicates that torsemide may be superior to furosemide with respect to improving HF functional status and reducing HF hospitalization, and there are mixed data regarding effect on reducing overall cardiovascular hospitalizations/mortality. Further, randomized data are necessary to definitively determine if torsemide can reduce risk of mortality and hospitalization among patients with HF.

Relationship between gut microbiota and markers of myocardial fibrosis in with chronic heart failure with preserved ejection fraction

Aim. To study the relationship of gut microbiota (GM) with serum myocardial fibrosis markers in patients with heart failure with preserved ejection fraction (HFpEF).

Material and methods. The composition of the gut microbiota among 42 patients with HFpEF aged 67,0 [64,0; 71,5] years (men, 57,1%) was assessed by 16S ribosomal ribonucleic acid sequencing. The quantitative determination of myocardial fibrosis markers was carried out by enzyme-linked immunosorbent assay. Correlation and multivariate regression analysis of relationships between the relative abundance of intestinal bacteria and the concentration of the procollagen type I carboxy-terminal propeptide (PICP) and N-terminal propeptide of procollagen type III (PIIINP) was carried out.

Results. The PICP and PIIINP concentrations were 918,0 [700,0; 1032,8] pg/ml and 6,2±2,7 pg/ml, respectively. Correlation analysis revealed a direct relationship between the relative abundance of Allisonella and PICP (r=0,32), as well as Blautia, Enterobаcteriaceae (unclassified) and PIIINP (r=0,37 and r=0,32), p<0,05. The inverse relationship was determined for the relative abundance of the genera Ruminococcus (r=-0,37), Ruminococcaceae (unclassified) (r=-0,31), Gemmiger (r=(-0,35) and PICP, as well as Bilophila and PIIICP (r=(-0,34). Multivariate regression found (normalized coefficient in parentheses) that the abundance of Butyricimonas (0,27) и Blautia (0,35) was directly related to the PICP levels, while the abundance of the genus Intestinimonas ((-0,23) showed an inverse association with the marker level. The abundance of most genera had an inverse relationship with PIIINP: Atopobium (-0,25), Cellulosilyticum (-0,31), Solobacterium (-0,32), Turicibacter (-0,47), Bilophila (-0,30). The directness of the association with  PIIINP concentration was demonstrated for the relative abundance of Paraprevotella (0,32) и Desulfovibrio (0,28). The p-value for all associations is <0,05.

Conclusion. The relative abundance of GM genera in patients with HFpEF is associated with fibrosis markers (PICP and PIIINP). The results obtained make it possible to deepen the understanding of the relationship between GM and pathogenesis of HFpEF, which may become a step towards understanding the GM role in the progression of left ventricular diastolic dysfunction and rationale for future studies.

Cardiac Fibrosis and Fibroblasts

Cardiac fibrosis is the excess deposition of extracellular matrix (ECM), such as collagen. Myofibroblasts are major players in the production of collagen, and are differentiated primarily from resident fibroblasts. Collagen can compensate for the dead cells produced by injury. The appropriate production of collagen is beneficial for preserving the structural integrity of the heart, and protects the heart from cardiac rupture. However, excessive deposition of collagen causes cardiac dysfunction. Recent studies have demonstrated that myofibroblasts can change their phenotypes. In addition, myofibroblasts are found to have functions other than ECM production. Myofibroblasts have macrophage-like functions, in which they engulf dead cells and secrete anti-inflammatory cytokines. Research into fibroblasts has been delayed due to the lack of selective markers for the identification of fibroblasts. In recent years, it has become possible to genetically label fibroblasts and perform sequencing at single-cell levels. Based on new technologies, the origins of fibroblasts and myofibroblasts, time-dependent changes in fibroblast states after injury, and fibroblast heterogeneity have been demonstrated. In this paper, recent advances in fibroblast and myofibroblast research are reviewed.

Impacts of Heart Failure and Physical Performance on Long-Term Mortality in Old Patients With Chronic Kidney Disease

Background: In patients with chronic kidney disease (CKD), physical functional limitations and heart failure (HF) are common, and each is associated with adverse outcomes. However, their joint effects on mortality are not clear.

Design and Methods: Using administration data from the geriatric department in a tertiary hospital, retrospective longitudinal analyses of patients aged ≥65 years with CKD were consecutively enrolled from February 2010 to November 2015. Baseline CKD stages, HF with reduced and preserved ejection fraction (HFrEF and HFpEF), Rockwood frailty index, handgrip strength (HGS), 6-m walking speed, and timed up-and-go test were used to predict the prevalence of frailty, physical disability, and all-cause mortality.

Results: Among 331 old patients with CKD, their mean age was 81.3 ± 6.6 years. CKD stages showed the following distributions: stage 3, 74.9%; stage 4, 15.7%; stage 5, 9.4%. The prevalence of HF was 23.3%, and Rockwood frailty was 74.3%. Rockwood frailty and HF were both significantly associated with CKD stages. After a mean follow-up period of 3.1 ± 2.1 years, 44 patients died, and a crude analysis showed that stage 4, stage 5 CKD, low HGS, and Rockwood frailty index were associated with mortality. Regarding the survival of these patients, the adjusted mortality hazard ratio for CKD stage 5 was 3.84 against stage 3A [95% confidence interval (CI) 1.51–9.75], 1.04 (95% CI 1.01–1.07) for higher Rockwood frailty score, 4.78 (95% CI 1.26–18.11) for HFrEF, and 3.47 (95% CI 1.15–10.42) for low HGS. Survival analysis using Kaplan–Meier survival plots showed that patients with both HF and poor HGS had the poorest survival.

Conclusions: Our study shows that both low physical performance and HF were common in old CKD patients and were associated with CKD stages. HF, frailty, and HGS all independently predicted the mortality of these CKD patients. The mortality is especially high amongst individuals with both HF and decreased HGS.

Cardiac fibrosis: Myofibroblast-mediated pathological regulation and drug delivery strategies

Cardiac fibrosis remains an unresolved problem in heart diseases. After initial injury, cardiac fibroblasts (CFs) are activated and subsequently differentiate into myofibroblasts (myoFbs) that are major mediator cells in the pathological remodeling. MyoFbs exhibit proliferative and secretive characteristics, and contribute to extracellular matrix (ECM) turnover, collagen deposition. The persistent functions of myoFbs lead to fibrotic scars and cardiac dysfunction. The anti-fibrotic treatment is hindered by the elusive mechanism of fibrosis and lack of specific targets on myoFbs. In this review, we will outline the progress of cardiac fibrosis and its contributions to the heart failure. We will also shed light on the role of myoFbs in the regulation of adverse remodeling. The communication between myoFbs and other cells that are involved in the heart injury and repair respectively will be reviewed in detail. Then, recently developed therapeutic strategies to treat fibrosis will be summarized such as i) chimeric antigen receptor T cell (CAR-T) therapy with an optimal target on myoFbs, ii) direct reprogramming from stem cells to quiescent CFs, iii) "off-target" small molecular drugs. The application of nano/micro technology will be discussed as well, which is involved in the construction of cell-based biomimic platforms and "pleiotropic" drug delivery systems.

Multimodality Imaging Assessment of Myocardial Fibrosis

Myocardial fibrosis, seen in ischemic and nonischemic cardiomyopathies, is associated with adverse cardiac outcomes. Noninvasive imaging plays a key role in early identification and quantification of myocardial fibrosis with the use of an expanding array of techniques including cardiac magnetic resonance, computed tomography, and nuclear imaging. This review discusses currently available noninvasive imaging techniques, provides insights into their strengths and limitations, and examines novel developments that will affect the future of noninvasive imaging of myocardial fibrosis.

Preclinical rodent models of cardiac fibrosis

Cardiac fibrosis (scarring), characterised by an increased deposition of extracellular matrix (ECM) proteins, is a hallmark of most types of cardiovascular disease and plays an essential role in heart failure progression. Inhibition of cardiac fibrosis could improve outcomes in patients with cardiovascular diseases and particularly heart failure. However, pharmacological treatment of the ECM build-up is still lacking. In this context, preclinical models of heart disease are important tools for understanding the complex pathogenesis involved in the development of cardiac fibrosis which in turn could identify new therapeutic targets and the facilitation of antifibrotic drug discovery. Many preclinical models have been used to study cardiac fibrosis and each model provides mechanistic insights into the many factors that contribute to cardiac fibrosis. This review discusses the most frequently used rodent models of cardiac fibrosis and also provides context for the use of particular models of heart failure.

Pragmatic Design of Randomized Clinical Trials for Heart Failure: Rationale and Design of the TRANSFORM-HF Trial

Randomized clinical trials are the foundation of evidence-based medicine and central to practice guidelines and patient care decisions. Nonetheless, randomized trials in heart failure (HF) populations have become increasingly difficult to conduct and are frequently associated with slow patient enrollment, highly selected populations, extensive data collection, and high costs. The traditional model for HF trials has become particularly difficult to execute in the United States, where challenges to site-based research have frequently led to modest U.S. representation in global trials. In this context, the TRANSFORM-HF (Torsemide Comparison with Furosemide for Management of Heart Failure) trial aims to overcome traditional trial challenges and compare the effects of torsemide versus furosemide among patients with HF in the United States. Loop diuretic agents are regularly used by most patients with HF and practice guidelines recommend optimal use of diuretic agents as key to a successful treatment strategy. Long-time clinical experience has contributed to dominant use of furosemide for loop diuretic therapy, although preclinical and small clinical studies suggest potential advantages of torsemide. However, due to the lack of appropriately powered clinical outcome studies, there is insufficient evidence to conclude that torsemide should be routinely recommended over furosemide. Given this gap in knowledge and the fundamental role of loop diuretic agents in HF care, the TRANSFORM-HF trial was designed as a prospective, randomized, event-driven, pragmatic, comparative-effectiveness study to definitively compare the effect of a treatment strategy of torsemide versus furosemide on long-term mortality, hospitalization, and patient-reported outcomes among patients with HF. (TRANSFORM-HF: ToRsemide compArisoN With furoSemide FORManagement of Heart Failure [TRANSFORM-HF]; NCT03296813).

Diffuse myocardial fibrosis: mechanisms, diagnosis and therapeutic approaches

Diffuse myocardial fibrosis resulting from the excessive deposition of collagen fibres through the entire myocardium is encountered in a number of chronic cardiac diseases. This lesion results from alterations in the regulation of fibrillary collagen turnover by fibroblasts, facilitating the excessive deposition of type I and type III collagen fibres within the myocardial interstitium and around intramyocardial vessels. The available evidence suggests that, beyond the extent of fibrous deposits, collagen composition and the physicochemical properties of the fibres are also relevant in the detrimental effects of diffuse myocardial fibrosis on cardiac function and clinical outcomes in patients with heart failure. In this regard, findings from the past 20 years suggest that various clinicopathological phenotypes of diffuse myocardial fibrosis exist in patients with heart failure. In this Review, we summarize the current knowledge on the mechanisms and detrimental consequences of diffuse myocardial fibrosis in heart failure. Furthermore, we discuss the validity and usefulness of available imaging techniques and circulating biomarkers to assess the clinicopathological variation in this lesion and to track its clinical evolution. Finally, we highlight the currently available and potential future therapeutic strategies aimed at personalizing the prevention and reversal of diffuse myocardial fibrosis in patients with heart failure.

Angiotensin Receptor Neprilysin Inhibitors in HFrEF: Is This the First Disease Modifying Therapy Drug Class Leading to a Substantial Reduction in Diuretic Need?

Despite significant advances in disease modifying therapy in heart failure (HF), diuretics have remained the cornerstone of volume management in all HF phenotypes. Diuretics, alongside their definite acute haemodynamic and symptomatic benefits, also possess many possible deleterious side effects. Moreover, questions remain regarding the prognostic impact of chronic diuretic use. To date, few data exist pertaining to diuretic reduction as a result of individual traditional guideline directed medical therapy in HF with reduced ejection fraction (HFrEF). However, diuretic reduction has been demonstrated with sacubitril/valsartan (angiotensin receptor-neprilysin inhibitor [ARNi]) from the PARADIGM study, as well as, post-marketing reports from our own group and others. Whether the ARNi compound represents the dawn of a new era, where effective therapies will have a more noticeable reduction on diuretic need, remains to be seen. The emergence of sodium glucose transport 2 inhibitors and guanylate cyclase stimulators may further exemplify this issue and potentially extend this benefit to HF patients outside of the HFrEF phenotype. In conclusion, emerging new therapies in HFrEF could reduce the reliance on diuretics in the management of this phenotype of HF. These developments further highlight the clinical importance to continually assess an individual's diuretic requirements through careful volume assessment.

Myocardial Interstitial Fibrosis in Nonischemic Heart Disease, Part 3/4: JACC Focus Seminar

Myocardial interstitial fibrosis (MIF) is a histological hallmark of several cardiac diseases that alter myocardial architecture and function and are associated with progression to heart failure. MIF is a diffuse and patchy process, appearing as a combination of interstitial microscars, perivascular collagen fiber deposition, and increased thickness of mysial collagen strands. Although MIF arises mainly because of alterations in fibrillar collagen turnover leading to collagen fiber accumulation, there are also alterations in other nonfibrillar extracellular matrix components, such as fibronectin and matricellular proteins. Furthermore, in addition to an excess of collagen, qualitative changes in collagen fibers also contribute to the detrimental impact of MIF. In this part 3 of a 4-part JACC Focus Seminar, we review the evidence on the complex mechanisms leading to MIF, as well as its contribution to systolic and diastolic cardiac dysfunction and impaired clinical outcomes in patients with nonischemic heart disease.

Myocardial Fibrosis in Heart Failure: Anti-Fibrotic Therapies and the Role of Cardiovascular Magnetic Resonance in Drug Trials

All heart muscle diseases that cause chronic heart failure finally converge into one dreaded pathological process that is myocardial fibrosis. Myocardial fibrosis predicts major adverse cardiovascular events and death, yet we are still missing the targeted therapies capable of halting and/or reversing its progression. Fundamentally it is a problem of disproportionate extracellular collagen accumulation that is part of normal myocardial ageing and accentuated in certain disease states. In this article we discuss the role of cardiovascular magnetic resonance (CMR) imaging biomarkers to track fibrosis and collate results from the most promising animal and human trials of anti-fibrotic therapies to date. We underscore the ever-growing role of CMR in determining the efficacy of such drugs and encourage future trialists to turn to CMR when designing their surrogate study endpoints.

COVID-19 myocarditis and prospective heart failure burden

Introduction: COVID-19 is causing considerable morbidity and mortality worldwide. Serious respiratory complications aside, the heart is also frequently involved. The mechanisms and the extent of the myocardial injury, along with the short and long-term cardiovascular (CV) outcomes in COVID-19 survivors remain unclear. Areas covered: myocardial injury has been found in a considerable proportion of hospitalized COVID-19 patients and is associated with a worse prognosis. The late onset of CV complications with myocarditis-like changes revealed by CMR has been reported in COVID-19 survivors. Previous observational studies on viral myocarditis provide evidence of a significant incomplete recovery with residual dysfunction and remodeling of left ventricle. Incomplete recovery is thought to be the result of persistent myocardial inflammation due to a post-viral autoimmune response. Considering the significant inflammatory nature of COVID-19, COVID-19 survivors may be at risk of developing persistent residual myocardial injury, the sequelae of which are unclear. Expert commentary: COVID-19 is an emerging threat for the heart. The extent of CV injury, along with the short and long-term sequelae, requires further investigation. The early detection of residual myocardial changes in COVID-19 survivors is of utmost importance in order to identify those patients at risk of CV complication development.

Cardiac magnetic resonance-derived fibrosis, strain and molecular biomarkers of fibrosis in hypertensive heart disease

AIMS

Myocardial fibrosis is a relevant component of hypertensive heart disease (HHD). Novel cardiovascular magnetic resonance (CMR) imaging techniques have shown potential in quantification of diffuse cardiac fibrosis, with T1 mapping, and estimating preclinical cardiac dysfunction, with strain analysis. Molecular biomarkers of fibrosis have been related with clinical outcomes and histologically proven myocardial fibrosis. The relationship between these CMR-imaging techniques and circulating biomarkers is not fully understood.

METHODS AND RESULTS

CMR was performed on a 3T scanner in 36 individuals with HHD. Extracellular volume fraction (ECV) and the partition coefficient were assessed using the T1 mapping technique shMOLLI. Longitudinal, circumferential and radial strain was assessed using CMR-Feature Tracking. Molecular biomarkers of collagen synthesis (PICP and PIIINP) and collagen degradation (CITP and MMP-1) were measured in blood using commercial kits. Correlation models showed a significant relationship of T1 mapping measures with left atrial diameter, LV mass, LV posterior wall thickness, LV end-diastolic volume and longitudinal strain. In fully adjusted regression models, ECV was associated with left atrial diameter (β=0.75, P = 0.005) and longitudinal strain (β = 0.43, P = 0.030); the partition coefficient was associated with LV posterior wall thickness (β = 0.53, P = 0.046). Strain measures were associated with cardiac geometry, and longitudinal strain was marginally associated with CITP.

CONCLUSION

In individuals with HHD, CMR-derived measures of myocardial fibrosis and function are related and might be useful tools for the identification and characterization of preclinical cardiac dysfunction and diffuse myocardial fibrosis. Molecular biomarkers of fibrosis were marginally associated with myocardial strain, but not with the extension of CMR-measured cardiac fibrosis.

Role of collagen turnover biomarkers in the noninvasive assessment of myocardial fibrosis: an update

The pro-fibrotic milieu, as the result of the extracellular matrix remodeling, is a central feature in the pathophysiology of heart disease and contributes to its high morbidity and mortality. Fibrosis is a recognized risk factor for development of heart failure and arrythmias and is usually detected by cardiac magnetic resonance or endomyocardial biopsy. Collagen type I and type III are major components of the collagen network, and the assessment of their derived biomarkers could serve as estimate of the myocardial fibrotic content. This review summarizes data from numerous studies in which these biomarkers have proven their diagnostic and prognostic utility, setting the stage for further randomized clinical trials that might translate into early implementation of antifibrotic therapies.

Comparative effects of furosemide and other diuretics in the treatment of heart failure: a systematic review and combined meta-analysis of randomized controlled trials

Diuretics have an essential role in the management of heart failure (HF). However, each drug has its own benefit and side effect. Side effects include fluid, electrolyte abnormalities, and acid-base disturbance. These adverse effects of diuretics predispose patients to serious cardiac arrhythmias and may increase the risk of arrhythmic mortality. Herein, we aim to summarize the relative efficacy and safety of all available diuretics used in the treatment of patients with HF. In June 2017, a systematic electronic database search was conducted in nine databases. All randomized controlled trials (RCTs) comparing the different diuretics used in HF were included for meta-analysis. The protocol was registered in Prospero with CRD42018084819. Among the included 54 studies (10,740 patients), 34 RCTs were eligible for quantitative network meta-analysis (NMA) and traditional meta-analysis while the other 20 studies were qualitatively analyzed. Our results showed that azosemide and torasemide caused a significant reduction in brain natriuretic peptide (BNP) level. Torasemide also caused a significant decrease in collagen volume fraction (CVF) and edema. No significant difference between the agents concerning glomerular filtration rate (GFR), water extraction, and sodium excretion was demonstrated. Regarding side effects, no significant difference among diuretics was observed in terms of hospital readmission and mortality rates. Diuretics are the main treatment of hypervolemia in HF patients. The choice of appropriate diuretic is essential for successful management and is mainly guided by patient clinical situations and the presence of other co-morbidities.

Biomarker of Collagen Turnover (C-Terminal Telopeptide) and Prognosis in Patients With Non- ST -Elevation Acute Coronary Syndromes

Background

Small studies have suggested an association between markers of collagen turnover and adverse outcomes in heart failure (HF). We examined C‐terminal telopeptide (beta‐CTx) and the risk of cardiovascular death or new or worsening HF in non–ST‐elevation acute coronary syndrome.

Methods and Results

We measured baseline serum beta‐CTx, NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide), hsTnT (high‐sensitivity cardiac troponin T) and hsCRP (high‐sensitivity C‐reactive protein) (Roche Diagnostics) in a nested biomarker analysis (n=4094) from a study of patients with non–ST‐elevation acute coronary syndrome. The relationship between quartiles of beta‐CTx and cardiovascular death or HF over a median follow‐up time of 12 months was analyzed using adjusted Cox models. Higher beta‐CTx levels identified a significantly higher risk of cardiovascular death/HF (Q4 10.9% versus Q1 3.8%, Logrank P<0.001). After multivariable adjustment, beta‐CTx in the top quartile (Q4) was associated with cardiovascular death/HF (Q4 versus Q1: adjusted hazard ratio 2.22 [1.50–3.27]) and its components (Q4 versus Q1: cardiovascular death: adjusted hazard ratio 2.48 [1.46–4.21]; HF: adjusted hazard ratio 2.04 [1.26–3.30]). In an adjusted multimarker model including NT‐proBNP, hsTnT, and hsCRP, beta‐CTx remained independently associated with cardiovascular death/HF (Q4 versus Q1: adjusted hazard ratio 1.98 [1.34–2.93]) and its components. Beta‐CTx correlated weakly with NT‐proBNP (r=0.17, P<0.001) and left ventricular ejection fraction (r=−0.05, P=0.008) and did not correlate with hsTnT (r=0.02, P=0.20), or hsCRP (r=−0.03, P=0.09).

Conclusions

Levels of beta‐CTx, a biomarker of collagen turnover, were associated with cardiovascular death and HF in patients with non–ST‐elevation acute coronary syndrome. This biomarker, which correlated only weakly or not significantly with traditional biomarkers of cardiovascular death and HF, may provide complementary pathobiological insight and risk stratification in these patients.

Torasemide versus furosemide in treatment of heart failure: A systematic review and meta-analysis of randomized controlled trials

AIM

Diuretics are a cornerstone in treatment of heart failure (HF). Torasemide is a loop diuretic with a potential advantage over other diuretics. We aim to meta-analyse and compare the effect of torasemide with furosemide in HF patients.

METHODS

A comprehensive literature search using 12 databases including PubMed, Scopus, and Web of Science was performed. All randomized controlled trials (RCTs) comparing furosemide and torasemide in HF patients were included and meta-analysed. We assessed the risk of bias using Cochrane Collaboration's tool. The protocol was registered in PROSPERO (CRD42016046112).

RESULTS

Eighteen RCTs with 1598 patients were included. There was a significant difference between torasemide 20 mg and furosemide 40 mg in increasing the urine volume (standard difference of the mean (SDM) [95% confidence interval] = -0.78 [-1.52 to -0.053], P = .036). Torasemide 10 mg and 10 to 20 mg have a significant effect on potassium excretion in comparison with furosemide 25 to 40 mg (P = .018 and .023, respectively). In general, torasemide and furosemide have no significant difference in mortality, edema improvement, weight loss, heart rate, and reducing systolic/diastolic blood pressure. However, oral torasemide has a significant lower hospital stay P < .001 and superior effect in improving ejection fraction P = .029.

CONCLUSION

Although not all results are statistically significant, torasemide has potential advantages on multiple aspects of HF management when compared with furosemide. More studies are needed to clarify these effects.

READY: relative efficacy of loop diuretics in patients with chronic systolic heart failure-a systematic review and network meta-analysis of randomised trials

The majority of patients with chronic heart failure (HF) receive long-term treatment with loop diuretics. The comparative effectiveness of different loop diuretics is unknown. We searched PubMed, clinicaltrials.gov , the Cochrane Central Register of Controlled Trials and the European Union Clinical Trials Register for randomised clinical trials exploring the efficacy of the loop diuretics azosemide, bumetanide, furosemide or torasemide in patients with HF. Comparators included placebo, standard medical care or any other active treatment. The primary endpoint was all-cause mortality. Secondary endpoints included cardiovascular mortality, HF-related hospitalisation and any combined endpoint thereof. Hypokalaemia and acute renal failure were defined as additional safety endpoints. Evidence was synthesised using network meta-analysis (NMA). Thirty-four trials reporting on 2647 patients were included. The overall quality of evidence was rated as moderate. NMA demonstrated no significant differences between loop diuretics with respect to all-cause mortality, cardiovascular mortality or hypokalaemia. In contrast, torasemide ranked best in terms of HF hospitalisation, and there was a trend towards benefits with torasemide with regard to occurrence of acute renal failure. Sensitivity analyses excluding trials with a follow-up < 6 months, trials with a cross-over design and those including < 25 patients confirmed the main results. We found no significant superiority of either loop diuretic with respect to mortality and safety endpoints. However, clinicians may prefer torasemide, as it was associated with fewer HF-related hospitalisations.

Diuretic Resistance in Heart Failure

Decompensated heart failure accounts for approximately 1 million hospitalizations in the United States annually, and this number is expected to increase significantly in the near future. Diuretics provide the initial management in most patients with fluid overload. However, the development of diuretic resistance remains a significant challenge in the treatment of heart failure. Due to the lack of a standard definition, the prevalence of this phenomenon remains difficult to determine, with some estimates suggesting that 25-30% of patients with heart failure have diuretic resistance. Certain characteristics, including low systolic blood pressures, renal impairment, and atherosclerotic disease, help predict the development of diuretic resistance. The underlying pathophysiology is likely multifactorial, with pharmacokinetic alterations, hormonal dysregulation, and the cardiorenal syndrome having significant roles. The therapeutic approach to this common problem typically involves increases in the diuretic dose and/or frequency, sequential nephron blockade, and mechanical fluid movement removal with ultrafiltration or peritoneal dialysis. Paracentesis is potentially useful in patients with intra-abdominal hypertension.

Does Chronic Kidney Disease Facilitate Malignant Myocardial Fibrosis in Heart Failure with Preserved Ejection Fraction of Hypertensive Origin?

In hypertensive patients with heart failure (HF) a serum biomarker combination of high carboxy-terminal propeptide of procollagen type-I (PICP) and low carboxy-terminal telopeptide of collagen type-I to matrix metalloproteinase-1 (CITP:MMP-1) ratio identifies a histomolecular phenotype of malignant myocardial fibrosis (mMF) associated with severe diastolic dysfunction (DD) and poor outcomes. As chronic kidney disease (CKD) facilitates MF and DD, we investigated the influence of CKD on the mMF biomarker combination in HF patients with preserved ejection fraction (HFpEF). Hypertensives (n = 365), 232 non-HF and 133 HFpEF, were studied, and 35% non-HF and 46% HFpEF patients had CKD (estimated glomerular filtration rate < 60 mL/min/1.73 m² or urine albumin-to-creatinine ratio ≥ 30 mg/g). Specific immunoassays were performed to determine biomarkers. Medians were used to establish the high PICP and low CITP:MMP-1 combination. A comparison with non-HF showed that the biomarker combination presence was increased in HFpEF patients, being associated with CKD in all patients. CKD influenced the association of the biomarker combination and HFpEF (p for interaction ≤ 0.019). The E:e’ ratio was associated with the biomarker combination in CKD patients. Among CKD patients with HFpEF, those with the biomarker combination exhibited higher (p = 0.016) E:e’ ratio than those without the pattern. These findings suggest that CKD facilitates the development of biomarker-assessed mMF and DD in hypertensive HFpEF patients.

Prognostic value of heart failure in hemodialysis-dependent end-stage renal disease patients with myocardial fibrosis quantification by extracellular volume on cardiac magnetic resonance imaging

Background

End-stage renal disease (ESRD) patients are at high cardiovascular risk, and myocardial fibrosis (MF) accounts for most of their cardiac events. The purpose of this study is to investigate the prognostic value and risk stratification of MF as measured by extracellular volume (ECV) on cardiac magnetic resonance (CMR) for heart failure (HF) in patients with hemodialysis-dependent ESRD.

Methods

Sixty-six hemodialysis ESRD patients and 25 matched healthy volunteers were prospectively enrolled and underwent CMR to quantify multiple parameters of MF by T1 mapping and late gadolinium enhancement (LGE). All ESRD patients were followed up for 11–30 months, and the end-point met the 2016 ESC guidelines for the definition of HF.

Results

Over a median follow-up of 18 months (range 11–30 months), there were 26 (39.39%) guideline-diagnosed HF patients in the entire cohort of ESRD subjects. The native T1 value was elongated, and ECV was enlarged in the HF cohort relative to the non-HF cohort and normal controls (native T1, 1360.10 ± 50.14 ms, 1319.39 ± 55.44 ms and 1276.35 ± 56.56 ms; ECV, 35.42 ± 4.42%, 31.85 ± 3.01% and 26.97 ± 1.87%; all p<0.05). In the cardiac strain analysis, ECV was significantly correlated with global radial strain (GRS) (r = − 0.501, p = 0.009), global circumferential strain (GCS) (r = 0.553, p = 0.005) and global longitudinal strain (GLS) (r = 0.507, p = 0.008) in ESRD patients with HF. Cox proportional hazard regression models revealed that ECV (hazard ratio [HR] = 1.160, 95% confidence interval: 1.022 to 1.318, p = 0.022) was the only independent predictor of HF in ESRD patients. It also had a higher diagnostic accuracy for detecting MF (area under the curve [AUC] = 0.936; 95% confidence interval: 0.864 to 0.976) than native T1 and post T1 (all p ≤ 0.002). Kaplan-Meier analysis revealed that the high-ECV group had a shorter median overall survival time than the low-ECV group (18 months vs. 20 months, log-rank p = 0.046) and that ESRD patients with high ECV were more likely to have HF.

Conclusions

Myocardial fibrosis quantification by ECV on CMR T1 mapping was shown to be an independent risk factor of heart failure, providing incremental prognostic value and risk stratification for cardiac events in ESRD patients.

Trial registration

Chinese Clinical Trial Registry ChiCTR-DND-17012976, 13/12/2017, Retrospectively registered.