Prompt coronary catheterization and revascularization have markedly improved the outcomes of myocardial infarction, but have also resulted in a growing number of surviving patients with permanent ...structural damage of the heart, which frequently leads to heart failure. There is an unmet clinical need for treatments for this condition
, particularly given the inability of cardiomyocytes to replicate and thereby regenerate the lost contractile tissue
. Here we show that expression of human microRNA-199a in infarcted pig hearts can stimulate cardiac repair. One month after myocardial infarction and delivery of this microRNA through an adeno-associated viral vector, treated animals showed marked improvements in both global and regional contractility, increased muscle mass and reduced scar size. These functional and morphological findings correlated with cardiomyocyte de-differentiation and proliferation. However, subsequent persistent and uncontrolled expression of the microRNA resulted in sudden arrhythmic death of most of the treated pigs. Such events were concurrent with myocardial infiltration of proliferating cells displaying a poorly differentiated myoblastic phenotype. These results show that achieving cardiac repair through the stimulation of endogenous cardiomyocyte proliferation is attainable in large mammals, however dosage of this therapy needs to be tightly controlled.
Endomyocardial biopsy (EMB) is an invasive procedure originally developed for the monitoring of heart transplant rejection. Over the year, this procedure has gained a fundamental complementary role ...in the diagnostic work-up of several cardiac disorders, including cardiomyopathies, myocarditis, drug-related cardiotoxicity, amyloidosis, other infiltrative and storage disorders, and cardiac tumours. Major advances in EMB equipment and techniques for histological analysis have significantly improved diagnostic accuracy of EMB. In recent years, advanced imaging modalities such as echocardiography with three-dimensional and myocardial strain analysis, cardiac magnetic resonance and bone scintigraphy have transformed the non-invasive approach to diagnosis and prognostic stratification of several cardiac diseases. Therefore, it emerges the need to re-define the current role of EMB for diagnostic work-up and management of cardiovascular diseases. The aim of this review is to summarize current knowledge on EMB in light of the most recent evidences and to discuss current indications, including challenging scenarios encountered in clinical practice.
COVID-19 is a deadly pulmonary disease with peculiar characteristics, which include variable clinical course and thrombophilia. A thorough understanding of the pathological correlates of the disease ...is still missing.
Here we report the systematic analysis of 41 consecutive post-mortem samples from individuals who died of COVID-19. Histological analysis is complemented by immunohistochemistry for cellular and viral antigens and the detection of viral genomes by in situ RNA hybridization.
COVID-19 is characterized by extensive alveolar damage (41/41 of patients) and thrombosis of the lung micro- and macro-vasculature (29/41, 71%). Thrombi were in different stages of organization, consistent with their local origin. Pneumocytes and endothelial cells contained viral RNA even at the later stages of the disease. An additional feature was the common presence of a large number of dysmorphic pneumocytes, often forming syncytial elements (36/41, 87%). Despite occasional detection of virus-positive cells, no overt signs of viral infection were detected in other organs, which showed non-specific alterations.
COVID-19 is a unique disease characterized by extensive lung thrombosis, long-term persistence of viral RNA in pneumocytes and endothelial cells, along with the presence of infected cell syncytia. Several of COVID-19 features might be consequent to the persistence of virus-infected cells for the duration of the disease.
This work was supported by a King's Together Rapid COVID-19 Call grant from King's College London. MG is supported by the European Research Council (ERC) Advanced Grant 787971 “CuRE” and by Programme Grant RG/19/11/34633 from the British Heart Foundation.
Objective
The orf8b protein of the coronavirus SARS-CoV, analogous to SARS-CoV-2, triggers the NLRP3 inflammasome in macrophages in vitro. Deregulated inflammasome-mediated release of interleukin-1 ...family cytokines is important in hyper-inflammatory syndromes, like happens in SARS-CoV-2-mediated cytokine release syndrome. We propose that an intense inflammasome formation characterizes the lungs of patients with fatal COVID-19 disease due to pneumonia and acute respiratory distress syndrome (ARDS).
Methods
Samples from four patients with confirmed COVID-19 pneumonia who had been hospitalized at the Hospital of the University of Trieste (Italy) and died of ARDS and four lung samples from a historical repository from subjects who had died of cardiopulmonary arrest and had not been placed on mechanical ventilation and without evidence of pulmonary infection at postmortem examination were collected. Pathology samples had been fixed in formalin 10% at time of collection and subsequently embedded in paraffin. We conducted staining for ASC (Apoptosis-associated Speck-like protein containing a Caspase recruitment domain), NLRP3 (NACHT, LRR, and PYD domains-containing protein 3), and cleaved caspase-1.
Results
Intense expression of the inflammasome was detected, mainly in leukocytes, within the lungs of all patients with fatal COVID-19 in the areas of lung injury. The number of ASC inflammasome specks per high power fields was significantly higher in the lungs of patients with fatal COVID-19 as compared with the lungs of control subjects (52 ± 22 vs 6 ± 3,
P
= 0.0064).
Conclusions
These findings identify the presence of NLRP3 inflammasome aggregates in the lungs of fatal COVID-19 pneumonia thus providing the potential molecular link between viral infection and cytokine release syndrome.
Latest statements from European and American societies recommend to rule out viral presence in endomyocardial biopsy (EMB) via polymerase chain reaction (PCR) analysis before starting ...immunosuppression or immunomodulation in acute lymphocytic myocarditis presenting with life‐threatening scenarios. However, recommendations in myocarditis are mostly based on heterogeneous studies enrolling patients with inflammatory cardiomyopathies and established heart failure rather than acute myocarditis. Thus, definitive evidence of a survival benefit from immunomodulation guided by viral presence is currently lacking. Finally, distinguishing innocent bystanders from causative agents among EMB‐detected viruses remain challenging and a major goal to achieve in the near future. Therefore, considerable divergence remains between official recommendations and clinical practice, including the possibility of starting immunosuppressive therapy empirically, without knowing viral PCR results. This review systematically discusses the unsolved issues of immunomodulation guided by viral presence in acute lymphocytic myocarditis, namely (i) virus epidemiology and prognosis, (ii) variability of viral presence rates, (iii) the role of potential viral bystander findings, and (iv) the main results of immunosuppression controlled trials in lymphocytic myocarditis. Furthermore, a practical approach for the critical use of viral presence analysis in guiding immunomodulation is provided, highlighting its importance before starting immunosuppression or immunomodulation. Future, multicentre studies are needed to address specific scenarios such as fulminant lymphocytic myocarditis and a virus‐tailored management as for parvovirus B19.
Myocarditis in Clinical Practice Sinagra, Gianfranco; Anzini, Marco; Pereira, Naveen L ...
Mayo Clinic proceedings,
09/2016, Letnik:
91, Številka:
9
Journal Article
Recenzirano
Odprti dostop
Myocarditis is a polymorphic disease characterized by great variability in clinical presentation and evolution. Patients presenting with severe left ventricular dysfunction and life-threatening ...arrhythmias represent a demanding challenge for the clinician. Modern techniques of cardiovascular imaging and the exhaustive molecular evaluation of the myocardium with endomyocardial biopsy have provided valuable insight into the pathophysiology of this disease, and several clinical registries have unraveled the disease's long-term evolution and prognosis. However, uncertainties persist in crucial practical issues in the management of patients. This article critically reviews current information for evidence-based management, offering a rational and practical approach to patients with myocarditis. For this review, we searched the PubMed and MEDLINE databases for articles published from January 1, 1980, through December 31, 2015, using the following terms: myocarditis, inflammatory cardiomyopathy, and endomyocardial biopsy. Articles were selected for inclusion if they represented primary data or were review articles published in high-impact journals. In particular, a risk-oriented approach is proposed. The different patterns of presentation of myocarditis are classified as low-, intermediate-, and high-risk syndromes according to the most recent evidence on prognosis, clinical findings, and both invasive and noninvasive testing, and appropriate management strategies are proposed for each risk class.
Purpose of Review
Cardiac masses frequently present significant diagnostic and therapeutic clinical challenges and encompass a broad set of lesions that can be either neoplastic or non-neoplastic. We ...sought to provide an overview of cardiac tumors using a cardiac chamber prevalence approach and providing epidemiology, imaging, histopathology, diagnostic workup, treatment, and prognoses of cardiac tumors.
Recent Findings
Cardiac tumors are rare but remain an important component of cardio-oncology practice. Over the past decade, the advances in imaging techniques have enabled a noninvasive diagnosis in many cases. Indeed, imaging modalities such as cardiac magnetic resonance, computed tomography, and positron emission tomography are important tools for diagnosing and characterizing the lesions. Although an epidemiological and multimodality imaging approach is useful, the definite diagnosis requires histologic examination in challenging scenarios, and histopathological characterization remains the diagnostic gold standard.
Summary
A comprehensive clinical and multimodality imaging evaluation of cardiac tumors is fundamental to obtain a proper differential diagnosis, but histopathology is necessary to reach the final diagnosis and subsequent clinical management.
Background Immune checkpoint inhibitors (ICI) are approved for treatment of recurrent or metastatic oropharyngeal head and neck squamous cell carcinoma in the first- and second-line settings. ...However, only 15-20% of patients benefit from this treatment, a feature increasingly ascribed to the peculiar characteristics of the tumor immune microenvironment (TIME). Methods Immune-related gene expression profiling (GEP) and multiplex immunofluorescence (mIF) including spatial proximity analysis, were used to characterize the TIME of 39 treatment-naïve oropharyngeal squamous cell carcinomas (OPSCC) and the corresponding lymph node metastases. GEP and mIF results were correlated with disease-free survival (DFS). HPV-positive tumors disclosed a stronger activation of several immune signalling pathways, as well as a higher expression of genes related to total tumor-infiltrating lymphocytes, CD8 T cells, cytotoxic cells and exhausted CD8 cells, than HPV-negative patients. Accordingly, mIF revealed that HPV-positive lesions were heavily infiltrated as compared to HPV-negative counterparts, with a higher density of T cells and checkpoint molecules. CD8+ T cells appeared in closer proximity to tumor cells, CD163+ macrophages and FoxP3+ cells in HPV-positive primary tumors, and related metastases. In HPV-positive lesions, PD-L1 expression was increased as compared to HPV-negative samples, and PD-L1+ tumor cells and macrophages were closer to PD-1+ cytotoxic T lymphocytes. Considering the whole cohort, a positive correlation was observed between DFS and higher levels of activating immune signatures and T cell responses, higher density of PD-1+ T cells and their closer proximity to tumor cells or PD-L1+ macrophages. HPV-positive patients with higher infiltration of T cells and macrophages had a longer DFS, while CD163+ macrophages had a negative role in prognosis of HPV-negative patients. Conclusions Our results suggest that checkpoint expression may reflect an ongoing antitumor immune response. Thus, these observations provide the rationale for the incorporation of ICI in the loco-regional therapy strategies for patients with heavily infiltrated treatment-naïve OPSCC, and for the combination of ICI with tumor-specific T cell response inducers or TAM modulators for the "cold" OPSCC counterparts. Keywords: Head and neck squamous cell carcinoma, Human papillomavirus, Tumor microenvironment, Immunotherapy, Multiplex immunofluorescence, Oropharyngeal carcinoma, Gene expression profile, Sex
Objective
Despite growing evidence about myocardial injury in hospitalized COronaVIrus Disease 2019 (COVID-19) patients, the mechanism behind this injury is only poorly understood and little is known ...about its association with SARS-CoV-2-mediated myocarditis. Furthermore, definite evidence of the presence and role of SARS-CoV-2 in cardiomyocytes in the clinical scenario is still lacking.
Methods
We histologically characterized myocardial tissue of 40 patients deceased with severe SARS-CoV-2 infection during the first wave of the pandemic. Clinical data were also recorded and analyzed. In case of findings supportive of myocardial inflammation, histological analysis was complemented by RT-PCR and immunohistochemistry for SARS-CoV-2 viral antigens and in situ RNA hybridization for the detection of viral genomes.
Results
Both chronic and acute myocardial damage was invariably present, correlating with the age and comorbidities of our population. Myocarditis of overt entity was found in one case (2.5%). SARS-CoV-2 genome was not found in the cardiomyocytes of the patient with myocarditis, while it was focally and negligibly present in cardiomyocytes of patients with known viral persistence in the lungs and no signs of myocardial inflammation. The presence of myocardial injury was not associated with myocardial inflammatory infiltrates.
Conclusions
In this autopsy cohort of COVID-19 patients, myocarditis is rarely found and not associated with SARS-CoV-2 presence in cardiomyocytes. Chronic and acute forms of myocardial damage are constantly found and correlate with the severity of COVID-19 disease and pre-existing comorbidities.
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