Current perspectives on the diagnosis and management of dilated cardiomyopathy Beyond heart failure: a Cardiomyopathy Clinic Doctor's point of view

The Role of Ventricular Assist Devices in Patients With Heart Failure Due to Dilated Cardiomyopathy: A Systematic Review

Dilated cardiomyopathy (DCM) is a prevalent heart muscle disease characterized by ventricular dilation and systolic dysfunction, leading to severe heart failure (HF) and often requiring heart transplantation (HTx). This systematic review aimed to synthesize information regarding the role of ventricular assist devices (VADs) in managing HF patients due to DCM. A comprehensive search was conducted across PubMed, Embase, Scopus, Web of Science, and Cochrane databases for studies published between 2014 and 2024. Inclusion criteria were studies involving adult patients with HF due to DCM treated with VADs. Exclusion criteria included non-human studies, pediatric populations, and non-peer-reviewed articles. Thirty-one studies met the inclusion criteria. The included studies demonstrated that the use of VADs in patients with DCM resulted in significant improvements in left ventricular ejection fraction (LVEF), myocardial fibrosis reduction, and reverse ventricular remodeling. Studies reported enhanced survival rates, reduced symptoms, and better quality of life. VADs served as a critical bridge to HTx and, in some cases, as long-term destination therapy. However, complications such as thrombus formation, anemia, and kidney failure were noted, emphasizing the need for vigilant monitoring and management. Continuous advancements in VAD technology and patient management protocols were found to be essential for optimizing outcomes. We conclude that VADs play a crucial role in managing advanced HF due to DCM by providing mechanical circulatory support, improving cardiac function, and enhancing patient survival and quality of life. Despite associated complications, VADs are invaluable for patients with severe HF, offering both immediate and long-term therapeutic benefits. Future research should focus on minimizing complications and further improving VAD technology to enhance patient outcomes.

[Régurgitation mitrale sévère due à la sarcoïdose cardiaque : une présentation clinique inhabituelle ; une étude de cas et des recherches antérieures]

Sarcoidosis is a granulomatous inflammatory disease that may involve multiple organ systems, including the heart. Cardiac manifestations are not rare and include atrial and ventricular arrhythmias, conduction abnormalities, congestive heart failure, valvular dysfunction, pericarditis, and sudden death. Although, cardiac sarcoidosis (CS) remains a diagnostic and therapeutic challenge. This article describes a case of a patient with a history of pulmonary sarcoidosis who presented with congestive heart failure, on the basis of severe mitral regurgitation secondary to cardiac infiltration and summarizes the published evidence regarding CS and mitral regurgitation.

Unraveling the molecular crosstalk and immune landscape between COVID-19 infections and ischemic heart failure comorbidity: New insights into diagnostic biomarkers and therapeutic approaches

BACKGROUND

Coronavirus disease 2019 (COVID-19), resulting from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), remains a persistent global health concern. Evidence has highlighted a significant association between COVID-19 and ischemic heart failure (IHF), contributing to disease progression and increased mortality. This study identified diagnostic biomarkers for these comorbidities and elucidated disease progression's molecular mechanisms.

METHODS

We retrieved differentially expressed gene (DEG) data for COVID-19 and IHF from publicly available microarray and RNA-Seq datasets to investigate the underlying mechanisms and potential pathways associated with the co-occurrence of COVID-19 and IHF. By intersecting the results from the two diseases, we obtained diagnostic biomarkers using SVM-RFE and LASSO algorithms. Animal experiments and immunological analyses were conducted to help understand the association between SARS-CoV-2 and IHF in patients, enabling early diagnosis of disease progression. Finally, we analyzed the regulatory network of critical genes and identified potential drug compounds that could target the genetic links identified in our study.

RESULTS

1974 common DEGs were identified between COVID-19 and IHF, contributing to disease progression and potential cancer risk by participating in immune and cancer-related pathways. In addition, we identified six hub genes (VDAC3, EIF2AK2, CHMP5, FTL, VPS4A, and CHMP4B) associated with the co-morbidity, and their diagnostic potential was confirmed through validation using relevant datasets and a mouse model. Functional enrichment analysis and examination of immune cell infiltration revealed immune dysregulation after disease progression. The comorbid hub genes exhibited outstanding immunomodulatory capacities. We also constructed regulatory networks tightly linked to both disorders, including transcription factors (TFs), miRNAs, and genes at both transcriptional and post-transcriptional levels. Finally, we identified 92 potential drug candidates to enhance the precision of anti-comorbidity treatment strategies.

CONCLUSION

Our study reveals a shared pathogenesis between COVID-19 and IHF, demonstrating that their coexistence exacerbates disease severity. By identifying and consolidating hub genes as pivotal diagnostic biomarkers for COVID-19 and IHF comorbidity, we have made significant advancements in understanding the underlying mechanisms of these conditions. Moreover, our study highlights dysregulated immunity and increased cancer risk in the advanced stages of disease progression. These findings offer novel perspectives for diagnosing and treating IHF progression during SARS-CoV-2 infection.

Efficacy and safety evaluation of Shenmai injections for dilated cardiomyopathy: A systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Shenmai Injection (SMI), a Chinese herbal injection, is widely used in China for the adjuvant treatment of patients with dilated cardiomyopathy (DCM), yet its clinical efficacy and safety remain controversial.

PURPOSE

The aim of this study was to systematically evaluate the efficacy and safety of SMI in the treatment of DCM.

METHODS

Randomised controlled trials (RCTs) of SMI in the treatment of DCM were searched for and collected from the PubMed, EMBASE, Cochrane Library, SinoMed, Wan Fang, CNKI, and VIP databases between the dates of establishment of each database and July 1, 2022. The methodological quality of the included studies was assessed, while the risk of bias was based on the Cochrane Collaboration tool. All data were analysed using the R software. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was applied to rate the quality of the evidence.

RESULTS

In total, 16 RCTs, including 1,455 participants, were examined in this study. Evidence showed that the combination of SMI treatment and conventional treatment appears to significantly increase the clinical efficacy rate (OR=3.65, 95%CI (2.52, 5.28), p < 0.01), improve cardiac function (e.g. increase left ventricular ejection fraction (LVEF) (MD=5.31, 95%CI (4.21, 6.40), p < 0.01), decrease left ventricular end-diastolic dimension (LVEDD) (MD=-4.57, 95% CI (-7.10, -2.04); p < 0.01) and left ventricular end-systolic diameter (LVESD) (MD=-2.46, 95% CI (-3.60, -1.33); p < 0.01), decrease brain natriuretic peptide (BNP) (MD=-215.85, 95% CI (-241.61, -190.10); p < 0.01) and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) (MD=-504.42, 95% CI (-687.73, -321.10); p < 0.01), and increase 6-min walk distance (6MWD) (MD=114.08, 95% CI (42.32, 185.85); p < 0.01).In addition, no serious adverse effects associated with SMI were observed during the study period, thus suggesting that SMI is safe. However, the quality of evidence for these results was rated as "very low" to "low", mainly due to the poor methodological quality of the included RCTs, the small sample size, the high heterogeneity, and potential publication bias.

CONCLUSION

In the present work, we provide evidence that combined SMI therapy is beneficial and safe for improving cardiac function in patients with DCM. However, due to limitations posed by the low methodological quality of the included trials, more rigorous and high-quality RCTs are needed to provide solid evidence.

A novel causative functional mutation in GATA6 gene is responsible for familial dilated cardiomyopathy as supported by in silico functional analysis

Dilated cardiomyopathy (DCM), one of the most common types of cardiomyopathies has a heterogeneous nature and can be seen in Mendelian forms. Next Generation Sequencing is a powerful tool for identifying novel variants in monogenic disorders. We used whole-exome sequencing (WES) and Sanger sequencing techniques to identify the causative mutation of DCM in an Iranian pedigree. We found a novel variant in the GATA6 gene, leading to substituting Histidine by Tyrosine at position 329, observed in all affected family members in the pedigree, whereas it was not established in any of the unaffected ones. We hypothesized that the H329Y mutation may be causative for the familial pattern of DCM in this family. The predicted models of GATA6 and H329Y showed the high quality according to PROCHECK and ERRAT. Nonetheless, simulation results revealed that the protein stability decreased after mutation, while the flexibility may have been increased. Hence, the mutation led to the increased compactness of GATA6. Overall, these data indicated that the mutation could affect the protein structure, which may be related to the functional impairment of GATA6 upon H329Y mutation, likewise their involvement in pathologies. Further functional investigations would help elucidating the exact mechanism.

Dilated cardiomyopathy in the era of precision medicine: latest concepts and developments

Dilated cardiomyopathy (DCM) is an umbrella term entailing a wide variety of genetic and non-genetic etiologies, leading to left ventricular systolic dysfunction and dilatation, not explained by abnormal loading conditions or coronary artery disease. The clinical presentation can vary from asymptomatic to heart failure symptoms or sudden cardiac death (SCD) even in previously asymptomatic individuals. In the last 2 decades, there has been striking progress in the understanding of the complex genetic basis of DCM, with the discovery of additional genes and genotype-phenotype correlation studies. Rigorous clinical work-up of DCM patients, meticulous family screening, and the implementation of advanced imaging techniques pave the way for a more efficient and earlier diagnosis as well as more precise indications for implantable cardioverter defibrillator implantation and prevention of SCD. In the era of precision medicine, genotype-directed therapies have started to emerge. In this review, we focus on updates of the genetic background of DCM, characteristic phenotypes caused by recently described pathogenic variants, specific indications for prevention of SCD in those individuals and genotype-directed treatments under development. Finally, the latest developments in distinguishing athletic heart syndrome from subclinical DCM are described.

Genetic Basis of Dilated Cardiomyopathy in Dogs and Its Potential as a Bidirectional Model

Simple Summary

Heart disease is a leading cause of death for both humans and dogs. Inherited heart diseases, including dilated cardiomyopathy (DCM), account for a proportion of these cases. Human and canine patients with DCM suffer from an enlarged heart that can no longer pump efficiently, resulting in heart failure. This causes symptoms or clinical signs like difficulty breathing, irregular heartbeat, and eventually death. The symptoms or clinical signs of this disease vary in age of onset at the beginning of symptoms, sex predisposition, and overall disease progression. Despite the many similarities in DCM in both species, only a few candidate genes so far have been linked to this disease in dogs versus tens of genes identified in human DCM. Additionally, the use of induced pluripotent stem cells, or engineered stem cells, has been widely used in the study of human genetic heart disease but has not yet been fully adapted to study heart disease in dogs. This review describes the current knowledge on the genetics and subtypes of naturally occurring DCM in dogs, and how advances in research might benefit the dog but also the human patient. Additionally, a novel method using canine engineered stem cells to uncover unknown contributions of mistakes in DNA to the progression of DCM will be introduced along with its applications for human DCM disease modeling and treatment.

Abstract

Cardiac disease is a leading cause of death for both humans and dogs. Genetic cardiomyopathies, including dilated cardiomyopathy (DCM), account for a proportion of these cases in both species. Patients may suffer from ventricular enlargement and systolic dysfunction resulting in congestive heart failure and ventricular arrhythmias with high risk for sudden cardiac death. Although canine DCM has similar disease progression and subtypes as in humans, only a few candidate genes have been found to be associated with DCM while the genetic background of human DCM has been more thoroughly studied. Additionally, experimental disease models using induced pluripotent stem cells have been widely adopted in the study of human genetic cardiomyopathy but have not yet been fully adapted for the in-depth study of canine genetic cardiomyopathies. The clinical presentation of DCM is extremely heterogeneous for both species with differences occurring based on sex predisposition, age of onset, and the rate of disease progression. Both genetic predisposition and environmental factors play a role in disease development which are identical in dogs and humans in contrast to other experimental animals. Interestingly, different dog breeds have been shown to develop distinct DCM phenotypes, and this presents a unique opportunity for modeling as there are multiple breed-specific models for DCM with less genetic variance than human DCM. A better understanding of DCM in dogs has the potential for improved selection for breeding and could lead to better overall care and treatment for human and canine DCM patients. At the same time, progress in research made for human DCM can have a positive impact on the care given to dogs affected by DCM. Therefore, this review will analyze the feasibility of canines as a naturally occurring bidirectional disease model for DCM in both species. The histopathology of the myocardium in canine DCM will be evaluated in three different breeds compared to control tissue, and the known genetics that contributes to both canine and human DCM will be summarized. Lastly, the prospect of canine iPSCs as a novel method to uncover the contributions of genetic variants to the pathogenesis of canine DCM will be introduced along with the applications for disease modeling and treatment.

Integrated Bioinformatics Algorithms and Experimental Validation to Explore Robust Biomarkers and Landscape of Immune Cell Infiltration in Dilated Cardiomyopathy

Background

The etiology of dilated cardiomyopathy (DCM) is unclear. Bioinformatics algorithms may help to explore the underlying mechanisms. Therefore, we aimed to screen diagnostic biomarkers and identify the landscape of immune infiltration in DCM.

Methods

First, the CIBERSORT algorithm was used to excavate the proportion of immune-infiltration cells in DCM and normal myocardial tissues. Meanwhile, the Pearson analysis and principal component analysis (PCA) were used to identify immune heterogeneity in different tissues. The Wilcoxon test, LASSO regression, and machine learning method were conducted to identify the hub immune cells. In addition, the differentially expressed genes (DEGs) were screened by the limma package, and DEGs were analyzed for functional enrichment. In the protein–protein interaction (PPI) network, multiple algorithms were used to calculate the score of each DEG for screening the hub genes. Subsequently, external datasets were used to further validate the expression of hub genes, and the receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficacy. Finally, we examined the expression of hub biomarkers in animal models.

Results

A total of 108 DEGs were screened, and these genes may be related to biological processes such as cytolysis, positive regulation of cytokine secretion, etc. Two types of hub immune cells [activated natural killer (NK) cells and eosinophils] and four hub genes (ASPN, CD163, IL10, and LUM) were identified in DCM myocardial tissues. CD163 was verified to have the capability to diagnose DCM with the most excellent specificity and sensitivity. It is worth mentioning that the combined CD163 and eosinophils may have better diagnostic efficacy. Moreover, the correlation analysis showed CD163 was negatively correlated with activated NK cells. Finally, the results of the mice model also indicated that CD163 might be involved in the occurrence of DCM.

Conclusion

ASPN, CD163, IL10, and LUM may have a potential predictive ability for DCM, and especially CD163 showed the most robust efficacy. Furthermore, activated NK cells and eosinophils may relate to the occurrence of DCM.

Circular RNA Expression for Dilated Cardiomyopathy in Hearts and Pluripotent Stem Cell-Derived Cardiomyocytes

Dilated cardiomyopathy (DCM) is a type of heart disease delimited by enlargement and dilation of one or both of the ventricles along with damaged contractility, which is often accompanied by the left ventricular ejection fraction (LVEF) less than 40%. DCM is progressive and always leads to heart failure. Circular RNAs (circRNAs) are unique species of noncoding RNAs featuring high cell-type specificity and long-lasting conservation, which normally are involved in the regulation of heart failure and DCM recently. So far, a landscape of various single gene or polygene mutations, which can cause complex human cardiac disorders, has been investigated by human-induced pluripotent stem cell (hiPSC) technology. Furthermore, DCM has been modeled as well, providing new perspectives on the disease study at a cellular level. In addition, current genome editing methods can not only repair defects of some genes, but also rescue the disease phenotype in patient-derived iPSCs, even introduce pathological-related mutations into wild-type strains. In this review, we gather up the aspects of the circRNA expression and mechanism in the DCM disease scenario, facilitating understanding in DCM development and pathophysiology in the molecular level. Also, we offer an update on the most relevant scientific progress in iPSC modeling of gene mutation-induced DCM.

Left Ventricular Layer-Specific Myocardial Strains in Children with Recovered Primary Dilated Cardiomyopathy: What Lies Beneath the Iceberg?

We aimed to detect residual cardiac dysfunction-if any-in children with recovered primary dilated cardiomyopathy (DCM) by using the left ventricular (LV) layer-specific myocardial strains. Fifty children with recovered primary DCM both clinically and echocardiographically were included as the patient group. Fifty healthy children of matched age and sex served as the control group. Echocardiographic evaluation was performed for all included children in the form of conventional echocardiography, tissue Doppler imaging (TDI), two-dimensional speckle tracking echocardiography (2D-STE), and LV layer-specific myocardial strain. Both LV systolic and diastolic functions measured by conventional echocardiography were similar in children with recovered DCM and the control group. There was a significant reduction in LV systolic and diastolic functions measured by TDI in the patient group. Moreover, there was a significant reduction of LV global longitudinal systolic strain (GLSS) by 2D-STE in children with recovered DCM. Interestingly, there was a significant reduction of LV layer-specific myocardial strain from endocardium to epicardium in children with recovered DCM compared to the healthy control. There was a significant positive correlation between different layer-specific myocardial strains and LV GLSS, LV ejection fraction, and LV peak systolic velocity. Left ventricular layer-specific myocardial strain can be a promising tool for early identifications of LV dysfunction in children with DCM. Subtle cardiac dysfunction is present in patients with recovered DCM, so long-term follow-up is recommended in these patients.

Importance of Genetic Testing in Dilated Cardiomyopathy: Applications and Challenges in Clinical Practice

Dilated cardiomyopathy (DCM) is a clinical syndrome characterized by left ventricular dilatation and contractile dysfunction. It is the most common cause of heart failure in young adults. The advent of next-generation sequencing has contributed to the discovery of a large amount of genomic data related to DCM. Mutations involving genes that encode cytoskeletal proteins, the sarcomere, and ion channels account for approximately 40% of cases previously classified as idiopathic DCM. In this scenario, geneticists and cardiovascular genetics specialists have begun to work together, building knowledge and establishing more accurate diagnoses. However, proper interpretation of genetic results is essential and multidisciplinary teams dedicated to the management and analysis of the obtained information should be considered. In this review, we approach genetic factors associated with DCM and their prognostic relevance and discuss how the use of genetic testing, when well recommended, can help cardiologists in the decision-making process.

[Molecular genetic basis of sudden cardiac death in the young with cardiomyopathy of various origins]

This paper provides a review of the modern literature devoted to the problem of forensic medical interpretation of the molecular genetic research of the young who died suddenly. The authors attempted to draw a parallel between the morphological markers of different variants of cardiomyopathy as the most common disease in sudden death at a young age and the association with genetic mutations in the genes responsible for the synthesis of sarcomer proteins, desmos and membrane channels. Based on the results of the analysis, further research is proposed to improve the accuracy of forensic diagnosis in cases of young deaths.

Trends in utilization, mortality, major complications, and cost after total artificial heart implantation in the United States (2009-2015)

OBJECTIVE

Total artificial heart (TAH) is a viable bridge to transplant (BTT) strategy for patients with severe biventricular failure or complex congenital heart disease. These patients have higher mortality and morbidity than patients undergoing left ventricular assist device (LVAD) implantation. To assess national trends in in-hospital mortality, major complications, cost, length of stay, and disposition of patients undergoing TAH implantation.

METHODS

Data from the National Inpatient Sample, the largest all-payer inpatient data set in the United States, and the US Census Bureau, for the years 2009 to 2015 were analyzed. Participants included all adult patients who received TAH from 2009 to 2015. Endpoints included in-hospital mortality, in-hospital complications, heart transplantation (HT) in the same admission, length of stay, cost, and disposition at the time of discharge.

RESULTS

We identified a total of 143 (weighted = 703) TAH implantations. The number of TAH implants increased during the study period (average annual change +5.8%, p = 0.03). Rates of in-hospital mortality and major complications including ischemic stroke, major bleeding, postoperative infections, acute kidney injury requiring dialysis, and HT did not change significantly over the study period. Although the length of stay and disposition patterns did not change over time, we found a significant increase in cost of hospitalization (average annual change +44,362, p = 0.01). The number of HT during the same hospital stay decreased significantly (average annual change -8.1%, p = 0.02).

CONCLUSION

In-hospital mortality and complication rates associated with TAH implantation remain increased and did not change in the era of continuous flow LVADs.

The R9H phospholamban mutation is associated with highly penetrant dilated cardiomyopathy and sudden death in a spontaneous canine model

Causative mutations for familial dilated cardiomyopathy (DCM) have been identified in the phospholamban gene. There are many poorly understood aspects about familial DCM (variable penetrance, expression) which may be studied in natural animal models. We characterized genetic aspects of familial DCM in a canine model with a high incidence of sudden death. A missense G > A mutation in exon 1 of the phospholamban gene that changed an amino acid from arginine to histidine was identified in affected dogs. This variant was predicted to be deleterious. We describe a spontaneous canine model of familial DCM and sudden death with the R9H mutation. In comparison to a reported human family, the variant was highly penetrant and resulted in sudden death. Genetic penetrance of this mutation may be influenced by genetic or environmental modifiers. The dog provides an excellent model in which to study complex aspects of familial DCM.

Cardiomyopathies and Related Changes in Contractility of Human Heart Muscle

About half of hypertrophic and dilated cardiomyopathies cases have been recognized as genetic diseases with mutations in sarcomeric proteins. The sarcomeric proteins are involved in cardiomyocyte contractility and its regulation, and play a structural role. Mutations in non-sarcomeric proteins may induce changes in cell signaling pathways that modify contractile response of heart muscle. These facts strongly suggest that contractile dysfunction plays a central role in initiation and progression of cardiomyopathies. In fact, abnormalities in contractile mechanics of myofibrils have been discovered. However, it has not been revealed how these mutations increase risk for cardiomyopathy and cause the disease. Much research has been done and still much is being done to understand how the mechanism works. Here, we review the facts of cardiac myofilament contractility in patients with cardiomyopathy and heart failure.