Noninvasive imaging in acute myocarditis

Tei Index Is a Useful Adjunctive Tool in the Diagnostic Workup of Patients with Acute Myocarditis

Background: Tei index (TI) is a combined myocardial performance index, which was found to be more sensitive for overall cardiac dysfunction than systolic or diastolic parameters alone. Currently, there is only limited evidence for this measure in the context of myocarditis. Thus, TI could add additional benefits to conventional diagnostic workup. Methods: TI of patients with myocarditis (n = 40), acute coronary syndrome (n = 29) and controls (n = 50) was retrospectively analyzed concerning its discriminatory ability for myocarditis. Results: TI was most pathological in patients with myocarditis (median 0.41 vs. 0.35 vs. 0.31, p < 0.0001). Its discriminatory ability was better than that of EF or E/e’ (AUCs: TI: 0.71, p < 0.0001; EF: 0.57, p = 0.112; E/e’: 0.64, p = 0.983), which was also verified in logistic regression analysis (B(SE) = 0.81(0.23), p = 0.0004). The association of TI with myocarditis remained significant even after correction for confounders in propensity score weighted analysis. Conclusions: The TI showed a better discriminatory ability for myocarditis than conventional echocardiographic parameters. Since TI is easily conducted, it might be a helpful adjunctive tool to supplement conventional diagnostic modalities in patients with suspected myocarditis.

COVID-Induced Fulminant Myocarditis

Viral-induced myocarditis has different presentations, from being asymptomatic to fatal arrhythmias. It is crucial to recognize and treat this condition early to improve morbidity and mortality.

We report a case of a 56-year-old male who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) three days ago and presented with syncope. The physical exam was relevant for right eyebrow laceration, tachycardia, and hypotension that responded to intravenous fluid, but two hours later, he had mental status changes, bradycardia, hypotension, and cardiac arrest. His repeated electrocardiogram (ECG) showed diffuse ST-segment elevation. Troponemia was evident in his blood work. Point-of-care ultrasound (POCUS) at the bedside showed dilated cardiomyopathy. Unfortunately, the patient re-arrested and needed advanced cardiovascular life support (ACLS).

The initial assessment of SARS-CoV-2, serial ECGs, and cardiac markers are essential for a prompt approach and therapy in COVID-19-induced myocarditis.

Quantitative Assessment of Late Gadolinium Enhancement and Edema at Cardiac Magnetic Resonance in Low-Risk Myocarditis Patients

In this study, we aimed to quantify LGE and edema at short-tau inversion recovery sequences on cardiac magnetic resonance (CMR) in patients with myocarditis. We retrospectively evaluated CMR examinations performed during the acute phase and at follow-up. Forty-seven patients were eligible for retrospective LGE assessment, and, among them, twenty-five patients were eligible for edema evaluation. Both groups were paired with age- and sex-matched controls. The median left ventricle LGE was 6.4% (interquartile range 5.0−9.2%) at the acute phase, 4.4% (3.3−7.2%) at follow-up, and 4.3% (3.0−5.3%) in controls, the acute phase being higher than both follow-up and controls (p < 0.001 for both), while follow-up and controls did not differ (p = 0.139). An optimal threshold of 5.0% was obtained for LGE with 87% sensitivity and 48% specificity; the positive likelihood ratio (LR) was 1.67, and the negative LR was 0.27. Edema was 12.8% (9.4−18.1%) at the acute phase, 7.3% (5.5−8.8%) at follow-up, and 6.7% (5.6−8.6%) in controls, the acute phase being higher than both follow-up and controls (both p < 0.001), while follow-up and controls did not differ (p = 0.900). An optimal threshold of 9.5% was obtained for edema with a sensitivity of 76% and a specificity of 88%; the positive LR was 6.33, and the negative LR was 0.27. LGE and edema thresholds are useful in cases of suspected mild myocarditis.

Emerging Role of Cardiac Magnetic Resonance Imaging in Diagnosing Myocarditis: A Blunder or The Way To Get the Problem Sorted?

Acute myocarditis is a disease affecting the myocardial tissue, which is caused by infections, rheumatic diseases, especially sarcoidosis, or certain therapies. Its diagnosis may be difficult, owing to its variable clinical presentation. In this setting, cardiac magnetic resonance plays a pivotal role in detecting myocardial inflammation through qualitative, semiquantitative, and quantitative parameters, in particular with the new quantitative techniques such as T1 and T2 mapping, combined or not with late gadolinium enhancement evaluation. This is in accordance with the revised Lake Louise criteria. In this review, the emerging role of the new cutting-edge cardiac magnetic resonance imaging techniques in diagnosing myocarditis is extensively presented.

Improving Endo-Myocardial Biopsy by Real-Time Spectral Tissue Sensing: A Feasibility Study

Objective: The aim of this research is to integrate spectral tissue sensing technology inside a cardiac bioptome for real-time measurements of tissue characteristics. Methods: Bioptome tip and handle components were designed and manufactured to house and guide optical fibers. The designed components were assembled on a cardiac bioptome together with optical fibers. A technical feasibility test was carried out to study the functionality of the instrument and the effect of the optical technology on the biopsy performance. Biopsy samples were taken from five different tissue types in a porcine heart and the resulting optical spectra were compared. Results: Spectral tissue sensing fibers were successfully integrated inside a conventional cardiac bioptome. The integrated instrument allowed differentiation between ventricular tissue, blood, and cardiac fat tissue based on blood and fat percentage and amount of scattering. Moreover, differences between scarred and non-scarred tissue were clearly visible. Conclusion: A first step has been made in the use of spectral tissue sensing for the detection of different tissue structures for endo-myocardial biopsy. The instrument was able to differentiate between various tissues, as well as between healthy and diseased cardiac tissues. Future research should focus on measurements of naturally diseased cardiac tissue, repeated measurements with statistical value, and improvements to the instrument design. Significance: Having the ability to measure tissue characteristics prior to acquiring a biopsy sample will not only allow easier positioning of the bioptome at the correct location, but can also prevent sampling undesired tissue or scar tissue from previous biopsies.

Immune Checkpoint Inhibitor-Associated Cardiotoxicity: Current Understanding on Its Mechanism, Diagnosis and Management

Immune checkpoint inhibitors (ICIs) that target cytotoxic T lymphocyte antigen 4, programmed cell death-1, and PD-ligand 1 have revolutionized cancer treatment, achieving unprecedented efficacy in multiple malignancies. ICIs are increasingly being used in early cancer settings and in combination with various other types of therapies, including targeted therapy, radiotherapy, and chemotherapy. However, despite the excellent therapeutic effect of ICIs, these medications typically result in a broad spectrum of toxicity reactions, termed immune-related adverse events (irAEs). Of all irAEs, cardiotoxicity, uncommon but with high mortality, has not been well recognized. Herein, based on previous published reports and current evidence, we summarize the incidence, diagnosis, clinical manifestations, underlying mechanisms, treatments, and outcomes of ICI-associated cardiotoxicity and discuss possible management strategies. A better understanding of these characteristics is critical to managing patients with ICI-associated cardiotoxicity.

Autoimmune myocarditis is not associated with left ventricular systolic dysfunction

BACKGROUND

Experimental autoimmune myocarditis (EAM) is a common animal model for the investigation of the pathophysiology of myocarditis. Because of diverging findings from previous studies, we performed serial echocardiographic examinations throughout the course of the disease and investigated the dimensions of the murine heart and left ventricular (LV) systolic function.

MATERIALS AND METHODS

Experimental autoimmune myocarditis was induced in male Balb/c mice by subcutaneous injection of a fragment of the α-myosin heavy chain (MyHC-α 614-629: Ac-SLKLMATLFSTYASAD). Transthoracic echocardiography was performed on days 0, 7 and 21 in healthy animals and mice with EAM.

RESULTS

Experimental autoimmune myocarditis was associated with a reduction in LV systolic function and an increase in LV internal diameter in diastole (LVIDd) and systole (LVIDs) 7 days postimmunization. After 21 days, EAM led to a significant increase in LV-thickness (1.3-fold increase in LV anterior wall diameter in diastole [LVAWDd]), but there was no difference in LV systolic function between immunized animals and healthy controls. LV-thickness correlated well with the severity of myocarditis in the histopathological examination (LVAWDd: rs = 0.603, P = 0.003, LV anterior wall diameter in systole (LVAWDs): rs = 0.718, P < 0.0001).

CONCLUSION

Our results indicate that EAM leads to an initial dilatation of the LV that is followed by ventricular "hypertrophy." On day 21, there was no significant difference in LV systolic function between immunized animals and controls. Furthermore, the ageing of the animals had a major impact on the echocardiographic parameters; therefore, the use of healthy age-matched controls seems warranted when echocardiography is performed in rodents.

Longitudinal 18F-FDG PET imaging in a rat model of autoimmune myocarditis

AIMS

Although mortality rate is very high, diagnosis of acute myocarditis remains challenging with conventional tests. We aimed to elucidate the potential role of longitudinal 2-Deoxy-2-18F-fluoro-D-glucose (18F-FDG) positron emission tomography (PET) inflammation monitoring in a rat model of experimental autoimmune myocarditis.

METHODS AND RESULTS

Autoimmune myocarditis was induced in Lewis rats by immunizing with porcine cardiac myosin emulsified in complete Freund's adjuvant. Time course of disease was assessed by longitudinal 18F-FDG PET imaging. A correlative analysis between in- and ex vivo18F-FDG signalling and macrophage infiltration using CD68 staining was conducted. Finally, immunohistochemistry analysis of the cell-adhesion markers CD34 and CD44 was performed at different disease stages determined by longitudinal 18F-FDG PET imaging. After immunization, myocarditis rats revealed a temporal increase in 18F-FDG uptake (peaked at week 3), which was followed by a rapid decline thereafter. Localization of CD68 positive cells was well correlated with in vivo18F-FDG PET signalling (R2 = 0.92) as well as with ex vivo18F-FDG autoradiography (R2 = 0.9, P < 0.001, respectively). CD44 positivity was primarily observed at tissue samples obtained at acute phase (i.e. at peak 18F-FDG uptake), while CD34-positive staining areas were predominantly identified in samples harvested at both sub-acute and chronic phases (i.e. at 18F-FDG decrease).

CONCLUSION

18F-FDG PET imaging can provide non-invasive serial monitoring of cardiac inflammation in a rat model of acute myocarditis.

Identification of targeting peptides for the diagnosis of myocarditis

Aim: Current diagnostic tests for myocarditis are invasive and have low diagnostic value. Our aim was to identify potential targeting peptides to detect early myocarditis following intravenous delivery. Materials & methods: We used an animal model of experimental autoimmune myocarditis and a phage display library to identify potential targeting peptides. After several steps, we selected two peptides, MyH-PhD-05 and MyH-PhD-120, for in vivo screening using fluorescent imaging. Immunofluorescence and proteonomic analysis was used to identify potential cellular and molecular targets of MyH-PhD-05. Echocardiography was used to assess functional changes. Results: Peptide MyH-PhD-05 was able to detect animals with severe myocarditis even in the absence of functional changes. Immunofluorescence demonstrated that MyH-PhD-05 colocalizes with CD4+ T cells and monocytes (CD11b+) in cardiac infiltrates. Conclusion: We identified potential targeting peptides for the diagnosis of myocarditis. Future studies will focus on better identification of potential targets and translating this technology to clinically relevant imaging modalities.

New-onset third-degree atrioventricular block because of autoimmune-induced myositis under treatment with anti-programmed cell death-1 (nivolumab) for metastatic melanoma

There has been considerable progress in treating malignant melanoma over the last few years. The immune-checkpoint-inhibitors nivolumab and pembrolizumab have been approved by the Food and Drug Administration in 2014 for the therapy of metastatic melanoma. Anti-programmed cell death-1-blocking antibodies are known to cause immune-related adverse events. Physicians should be aware of common and rare side effects and pay attention to new ones. We therefore report a severe and life-threatening side effect of anti-programmed cell death-1 immunotherapy with nivolumab that has not been previously reported: the development of a third-degree atrioventricular block. After a second infusion with nivolumab, our patient developed a troponin I-positive and autoantibody-positive myositis and a few days later a new-onset third-degree atrioventricular block. This is most likely because of an autoimmune-induced myositis with a cardiac impairment in terms of a myocarditis, which led to an impairment of the conduction of cardiac electrical stimuli.

Application of Neonatologist Performed Echocardiography in the Assessment and Management of Neonatal Heart Failure unrelated to Congenital Heart Disease

Neonatal heart failure (HF) is a progressive disease caused by cardiovascular and non-cardiovascular abnormalities. The most common cause of neonatal HF is structural congenital heart disease, while neonatal cardiomyopathy represents the most common cause of HF in infants with a structurally normal heart. Neonatal cardiomyopathy is a group of diseases manifesting with various morphological and functional phenotypes that affect the heart muscle and alter cardiac performance at, or soon after birth. The clinical presentation of neonates with cardiomyopathy is varied, as are the possible causes of the condition and the severity of disease presentation. Echocardiography is the selected method of choice for diagnostic evaluation, follow-up and analysis of treatment results for cardiomyopathies in neonates. Advances in neonatal echocardiography now permit a more comprehensive assessment of cardiac performance that could not be previously achieved with conventional imaging. In this review, we discuss the current and emerging echocardiographic techniques that aid in the correct diagnostic and pathophysiological assessment of some of the most common etiologies of HF that occur in neonates with a structurally normal heart and acquired cardiomyopathy and we provide recommendations for using these techniques to optimize the management of neonate with HF.

Cardiogenic Shock during First Infusion of Anthracycline Chemotherapy in a Patient with Hodgkin Lymphoma: An Unusual Event

INTRODUCTION

Hodgkin lymphoma (HL) is one of the most common types of cancers of the lymphatic system. The currently available therapies enable a cure in approximately 80-85% of treated patients. However, the cardiotoxicity of HL treatment has become a major cause of morbidity and mortality in survivors mainly related to the use of anthracycline.

CASE REPORT

An HL, staged IIIB, was diagnosed in a 60-year-old man with no cardiovascular disease. During the first cycle of ABVD chemotherapy (Adriamycin; bleomycin; vinblastine; dacarbazine), near the end of the dacarbazine infusion, the patient presented a sudden cardiogenic shock characterized by a severe left ventricular systolic dysfunction. Laboratory and instrumental examinations performed did not suggest any specific etiology. After 15 days of medical support, the patient presented a complete cardiac function and clinical recovery. Subsequently bendamustine chemotherapy was started because of its limited extrahematological toxicity, but after 4 cycles the patient had progressive disease and died of septic shock. We concluded that a very rare hyperacute anthracycline cardiotoxicity was the most likely reason for this critical scenario.

CONCLUSIONS

This rare event stresses our inability to correctly predict the risk of a patient developing cardiotoxicity and also highlights the need to improve the knowledge of underlying pathophysiological mechanisms; in fact, it suggests a possible genetic predisposition to develop cardiotoxicity due to a relatively limited dosage.

Feasibility and Diagnostic Value of Cardiovascular Magnetic Resonance Imaging After Acute Ischemic Stroke of Undetermined Origin

Background and Purpose—

Etiology of acute ischemic stroke remains undetermined (cryptogenic) in about 25% of patients after state-of-the-art diagnostic work-up.

Methods—

One-hundred and three patients with magnetic resonance imaging (MRI)–proven acute ischemic stroke of undetermined origin were prospectively enrolled and underwent 3-T cardiac MRI and magnetic resonance angiography of the aortic arch in addition to state-of-the-art diagnostic work-up, including transesophageal echocardiography (TEE). We analyzed the feasibility, diagnostic accuracy, and added value of cardiovascular MRI (cvMRI) compared with TEE for detecting sources of stroke.

Results—

Overall, 102 (99.0%) ischemic stroke patients (median 63 years [interquartile range, 53–72], 24% female, median NIHSS (National Institutes of Health Stroke Scale) score on admission 2 [interquartile range, 1–4]) underwent cvMRI and TEE in hospital; 89 (86.4%) patients completed the cvMRI examination. In 93 cryptogenic stroke patients, a high-risk embolic source was found in 9 (8.7%) patients by cvMRI and in 11 (11.8%) patients by echocardiography, respectively. cvMRI and echocardiography findings were consistent in 80 (86.0%) patients, resulting in a degree of agreement of κ=0.24. In 82 patients with cryptogenic stroke according to routine work-up, including TEE, cvMRI identified stroke etiology in additional 5 (6.1%) patients. Late gadolinium enhancement consistent with previous myocardial infarction was found in 13 (14.6%) out of 89 stroke patients completing cvMRI. Only 2 of these 13 patients had known coronary artery disease.

Conclusions—

Our study demonstrated that cvMRI was feasible in the vast majority of included patients with acute ischemic stroke. The diagnostic information of cvMRI seems to be complementary to TEE but is not replacing echocardiography after acute ischemic stroke.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT01917955.

Exercise-Triggered Chest Pain as an Isolated Symptom of Myocarditis in Children

In childhood, chest pain occurring at exercise is a common complaint. A cardiac etiology for it is exceptionally found, explaining that most children do not undergo systematic cardiological investigation. However, chest pain at exercise may manifest as the unique symptom of a viral myocarditis. Recognizing this form of myocardial injury, however, might help to avoid clinical deterioration by providing adequate care. In this paper, we report on two children presenting with the unique clinical symptom of chest pain related to physical activity and in whom laboratory and cardiac investigations suggested transient myocardial damage related to myocarditis.