Long-term outcome of fulminant myocarditis as compared with acute (nonfulminant) myocarditis

Management of Myocarditis-Related Cardiomyopathy in Adults

Myocarditis is generally a mild and self-limited consequence of systemic infection of cardiotropic viruses. However, patients can develop a temporary or permanent impairment of cardiac function including acute cardiomyopathy with hemodynamic compromise or severe arrhythmias. In this setting, specific causes of inflammation are associated with variable risks of death and transplantation. Recent translational studies suggest that treatments tailored to specific causes of myocarditis may impact clinical outcomes when added to guideline-directed medical care. This review summarizes recent advances in translational research that influence the utility of endomyocardial biopsy for the management of inflammatory cardiomyopathies. Emerging therapies for myocarditis based on these mechanistic hypotheses are entering clinical trials and may add to the benefits of established heart failure treatment.

Tissue Characterization by Mapping and Strain Cardiac MRI to Evaluate Myocardial Inflammation in Fulminant Myocarditis

BACKGROUND

The clinical value of novel mapping techniques and strain measures to assess myocardial inflammation in fulminant myocarditis (FM) has not been fully explored.

PURPOSE

To evaluate the ability of mapping and strain cardiac MRI to assess myocardial inflammation in patients with FM, and to which degree the strain metrics correlate with myocardial edema.

STUDY TYPE

Prospective.

POPULATION

Twenty-nine patients (37 ± 16 years, 48% male) with FM and 29 patients with nonfulminant acute myocarditis (NFAM) (29 ± 14 years, 69% male).

FIELD STRENGTH/SEQUENCE

3.0T; Cine imaging, black blood T₂ -weighted imaging, T₁ mapping, T₂ mapping, and late gadolinium enhancement.

ASSESSMENT

Native T₁ , extracellular volume (ECV), and T₂ were measured. Myocardial strain was evaluated by feature tracking.

STATISTICAL TESTS

Student's t- or Mann-Whitney U-test. Spearman correlation analysis.

RESULTS

The myocardial edema rate (2.6 ± 0.7 vs. 1.6 ± 0.2, P < 0.001) and late gadolinium enhancement (LGE) mass (16.5 [11.7, 41.7] vs. 6.9 [2.2, 15.8] g, P < 0.001) were significantly increased in FM patients when compared to the NFAM group. LGE in the FM group was predominantly located in the septal wall, and 38% of the patients showed a diffuse LGE pattern. Native T₁ , ECV, and T₂ values in the FM group were significantly more elevated than those with NFAM, while global peak radial, circumferential, and longitudinal strain values were significantly reduced (all P < 0.001). Circumferential strain showed the strongest correlations with ECV (r = 0.72, P < 0.001).

DATA CONCLUSION

Patients with FM showed significant differences in LGE patterns, increased edema, and decreased strain measurements compared to those with NFAM. Circumferential strain showed significant associations with quantitative cardiac MRI parameters of myocardial inflammation.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 2 J. Magn. Reson. Imaging 2020;52:930-938.

Sudden cardiac death in patients with myocarditis: Evaluation, risk stratification, and management

Myocarditis is a major cause of sudden cardiac death (SCD) and dilated cardiomyopathy (DCM) in young adults. Cardiac magnetic resonance is the established tool for the diagnosis of myocarditis, and late gadolinium enhancement detected on cardiac magnetic resonance imaging is the strongest independent predictor of SCD, all-cause mortality, and cardiac mortality. Several other factors have been associated with SCD or cardiac transplantation including New York Heart Association functional class III/IV, reduced left ventricular ejection fraction <35%, and right ventricular ejection fraction ≤45%. A fragmented QRS and a prolonged QTc interval on an electrocardiogram are predictors of VAs. The postulated mechanism of VA in acute myocarditis is ion channel dysfunction and inflammation that alter intracellular signaling, producing interstitial edema and fibrosis and thereby causing conduction abnormalities. VAs in chronic myocarditis are generally due to scar-mediated reentry. Treatment of myocarditis is tailored toward supportive care and symptomatic relief. The subset of patients who develop DCM should be treated with heart failure medications according to professional guideline recommendations. Indications for an implantable cardioverter-defibrillator are similar to those for nonischemic cardiomyopathy; however, an implantable cardioverter-defibrillator should be held in the acute phase of myocarditis to allow left ventricular ejection fraction recovery, and a wearable cardioverter-defibrillator may be beneficial for some patients. Antiarrhythmic medications are reserved for patients with symptomatic nonsustained or sustained VAs. Radiofrequency ablation appears to be an effective treatment option for VAs; however, more data on its safety and effectiveness are needed. This review addresses risk factors of SCD and VAs in patients with myocarditis with special emphasis on treatment and prevention of these outcomes.

Viral Myocarditis-Incidence, Diagnosis and Management

Viral myocarditis has an incidence rate of 10 to 22 per 100,000 individuals. The presentation pattern of viral myocarditis can range from nonspecific symptoms of fatigue and shortness of breath to more aggressive symptoms that mimic acute coronary syndrome. After the initial acute phase presentation of viral myocarditis, the virus may be cleared, resulting in full clinical recovery; the viral infection may persist; or the viral infection may lead to a persistent autoimmune-mediated inflammatory process with continuing symptoms of heart failure. As a result of these 3 possibilities, the diagnosis, prognosis, and treatment of viral myocarditis can be extremely unpredictable and challenging for the clinician. Herein, the incidence, etiology, definition and classification, clinical manifestation, diagnosis, pathogenesis, prognosis, and treatment of viral myocarditis are reviewed, and how acute clinical care teams might differentiate between viral myocarditis and other acute cardiac conditions is discussed.

Recognition and Initial Management of Fulminant Myocarditis: A Scientific Statement From the American Heart Association

Fulminant myocarditis (FM) is an uncommon syndrome characterized by sudden and severe diffuse cardiac inflammation often leading to death resulting from cardiogenic shock, ventricular arrhythmias, or multiorgan system failure. Historically, FM was almost exclusively diagnosed at autopsy. By definition, all patients with FM will need some form of inotropic or mechanical circulatory support to maintain end-organ perfusion until transplantation or recovery. Specific subtypes of FM may respond to immunomodulatory therapy in addition to guideline-directed medical care. Despite the increasing availability of circulatory support, orthotopic heart transplantation, and disease-specific treatments, patients with FM experience significant morbidity and mortality as a result of a delay in diagnosis and initiation of circulatory support and lack of appropriately trained specialists to manage the condition. This scientific statement outlines the resources necessary to manage the spectrum of FM, including extracorporeal life support, percutaneous and durable ventricular assist devices, transplantation capabilities, and specialists in advanced heart failure, cardiothoracic surgery, cardiac pathology, immunology, and infectious disease. Education of frontline providers who are most likely to encounter FM first is essential to increase timely access to appropriately resourced facilities, to prevent multiorgan system failure, and to tailor disease-specific therapy as early as possible in the disease process.

Heart non-specific effector CD4+ T cells protect from postinflammatory fibrosis and cardiac dysfunction in experimental autoimmune myocarditis

Heart-specific CD4⁺ T cells have been implicated in development and progression of myocarditis in mice and in humans. Here, using mouse models of experimental autoimmune myocarditis (EAM) we investigated the role of heart non-specific CD4⁺ T cells in the progression of the disease. Heart non-specific CD4⁺ T cells were obtained from DO11.10 mice expressing transgenic T cell receptor recognizing chicken ovalbumin. We found that heart infiltrating CD4⁺ T cells expressed exclusively effector (T_eff) phenotype in the EAM model and in hearts of patients with lymphocytic myocarditis. Adoptive transfer experiments showed that while heart-specific T_eff infiltrated the heart shortly after injection, heart non-specific T_eff effectively accumulated during myocarditis and became the major heart-infiltrating CD4⁺ T cell subset at later stage. Restimulation of co-cultured heart-specific and heart non-specific CD4⁺ T cells with alpha-myosin heavy chain antigen showed mainly Th1/Th17 response for heart-specific T_eff and up-regulation of a distinct set of extracellular signalling molecules in heart non-specific T_eff. Adoptive transfer of heart non-specific T_eff in mice with myocarditis did not affect inflammation severity at the peak of disease, but protected the heart from adverse post-inflammatory fibrotic remodelling and cardiac dysfunction at later stages of disease. Furthermore, mouse and human T_eff stimulated in vitro with common gamma cytokines suppressed expression of profibrotic genes, reduced amount of α-smooth muscle actin filaments and decreased contraction of cardiac fibroblasts. In this study, we provided a proof-of-concept that heart non-specific T_eff cells could effectively contribute to myocarditis and protect the heart from the dilated cardiomyopathy outcome.

Temporal echocardiography findings in patients with fulminant myocarditis: beyond ejection fraction decline

The features of myocardial strains from speckle-tracking echocardiography (STE) have not been well defined in fulminant myocarditis (FM) patients. In this study, changes in the left ventricular ejection fraction (LVEF) and global and layer-specific myocardial strains over time were monitored. We aimed to determine the echocardiographic patterns of FM and ascertain their significance in FM treatment. Twenty patients who were clinically diagnosed with FM and received mechanical life support were prospectively enrolled. Conventional echocardiographic measurements were obtained, and serial strain echocardiography was performed from admission to hospital discharge until LVEF recovery (> 50%). Global/regional peak systolic longitudinal strains (GLS/RLS) and layer-specific longitudinal strains were quantified, and their changes with time were monitored in 14 FM patients. All patients had severely impaired cardiac function. Steep improvement in LVEF and GLS were observed within 6 days. Layer-specific strain analysis showed that reduction at admission or recovery at discharge in the endocardium and epicardium strains were equal. In conclusion, FM patients who received mechanical circulatory supports exhibited steep improvement in ventricular function within 6 days. The patchy and diffused distribution pattern of reduced RLS and equally and severely impaired strain in the endocardium and epicardium are valuable features in the diagnosis of FM.

Fulminant Myocarditis: Epidemiology, Pathogenesis, Diagnosis, and Management

Fulminant myocarditis (FM) is a rare, distinct form of myocarditis that has been difficult to classify. Since 1991, the definition of FM has evolved, and it is currently considered an acute illness with hemodynamic derangement and arrhythmias due to a severe inflammatory process requiring support of cardiac pump function and/or urgent management of serious arrhythmias. Diagnosis is aided through use of biomarkers and cardiac imaging, but endocardial biopsy remains the gold standard. Recent evidence has revealed that patients with FM are significantly more likely to die or require heart transplantation than those with the nonfulminant form, refuting previous studies proposing a paradoxically low mortality in patients with FM. Acute hemodynamic derangement is managed by intensive contemporary pharmacologic and interventional approaches, whereas the role of immunosuppressive therapy has not been clarified. Early recognition and aggressive management are essential for favorable outcomes. In conclusion, FM is an inflammatory process requiring intensive support, and it causes a higher morbidity and mortality than acute nonfulminant myocarditis.

Arrhythmogenic Inflammatory Cardiomyopathy in Autoimmune Rheumatic Diseases: A Challenge for Cardio-Rheumatology

Ventricular arrhythmia (VA) in autoimmune rheumatic diseases (ARD) is an expression of autoimmune inflammatory cardiomyopathy (AIC), caused by structural, electrical, or inflammatory heart disease, and has a serious impact on a patient’s outcome. Myocardial scar of ischemic or nonischemic origin through a re-entry mechanism facilitates the development of VA. Additionally, autoimmune myocardial inflammation, either isolated or as a part of the generalized inflammatory process, also facilitates the development of VA through arrhythmogenic autoantibodies and inflammatory channelopathies. The clinical presentation of AIC varies from oligo-asymptomatic presentation to severe VA and sudden cardiac death (SCD). Both positron emission tomography (PET) and cardiovascular magnetic resonance (CMR) can diagnose AIC early and be useful tools for the assessment of therapies during follow-ups. The AIC treatment should be focused on the following: (1) early initiation of cardiac medication, including ACE-inhibitors, b-blockers, and aldosterone antagonists; (2) early initiation of antirheumatic medication, depending on the underlying disease; and (3) potentially implantable cardioverter–defibrillator (ICD) and/or ablation therapy in patients who are at high risk for SCD.

Successful treatment of fulminant myocarditis in an adult in emergency department: A case report

RATIONALE

Fulminant myocarditis (FM) has poor prognosis and the usual treatment is inotropes and symptomatic support. The initiation of extracorporeal membrane oxygenation (ECMO) and intra-aortic balloon pumping (IABP) in the emergency department (ED) is a rare event.

PATIENT CONCERNS

We report the case of a 45-year-old man with a complaint of 4 days of high fever and dry cough in the emergency department.

DIAGNOSIS

Transthoracic echocardiogram and the medical history showed presumptive diagnosis was fulminant myocarditis with cardiogenic shock.

INTERVENTIONS

The patient's condition deteriorated drastically and ECMO was initiated immediately after admission. He experienced electrical storm twice during ECMO support and was successfully treated with the combination with IABP.

OUTCOMES

ECMO and IABP were continued for 11 and 14 days respectively. The patient was discharged on the 81th day after admission, with all his laboratory tests returned to normal.

LESSONS SUBSECTIONS

The early initiation of ECMO and IABP in the ED is potentially life-saving for suitable patients with FM. It appears promising but has not yet been routinely implemented in underdeveloped and developing countries.

Inflammation in myocardial disease: From myocarditis to dilated cardiomyopathy

Dilated cardiomyopathy (DCM) is a heterogeneous group of myocardial diseases clinically defined by the presence of left ventricular dilatation and contractile dysfunction. Among various causes of DCM, a progression from viral myocarditis to DCM has long been hypothesized. Supporting this possibility, studies by endomyocardial biopsy, the only method to obtain a definite diagnosis of myocarditis at present, have provided evidence of inflammation in the myocardium in DCM patients. A number of experimental studies have elucidated a cell-mediated autoimmune mechanism triggered by viral infection in the progression of myocarditis to DCM. In addition, the important role of inflammation in the pathogenesis of heart failure has been recognized, and many terms including myocarditis, inflammatory cardiomyopathy, and inflammatory DCM have been used for myocardial diseases associated with inflammation. This review discusses the pathophysiology of inflammation in the myocardium, and refers to diagnosis and treatment based on these concepts.

Severe heart failure and the need for mechanical circulatory support and heart transplantation in pediatric patients with myocarditis: Results from the prospective multicenter registry "MYKKE"

Myocarditis represents an important cause for acute heart failure. MYKKE, a prospective multicenter registry of pediatric patients with myocarditis, aims to gain knowledge on courses, diagnostics, and therapy of pediatric myocarditis. The role of mechanical circulatory support (MCS) in children with severe heart failure and myocarditis is unclear. The aim of this study was to determine characteristics and outcome of patients with severe heart failure requiring MCS and/or heart transplantation. The MYKKE cohort between September 2013 and 2016 was analyzed. A total of 195 patients were prospectively enrolled by 17 German hospitals. Twenty-eight patients (14%) received MCS (median 1.5 years), more frequently in the youngest age group (0-2 years) than in the older groups (P < 0.001; 2-12 and 13-18 years). In the MCS group, 50% received a VAD, 36% ECMO, and 14% both, with a survival rate of 79%. The weaning rate was 43% (12/28). Nine (32%) patients were transplanted, one had ongoing support, and six (21%) died. Histology was positive for myocarditis in 63% of the MCS group. Patients within the whole cohort with age <2 years and/or ejection fraction <30% had a significantly worse survival with high risk for MCS, transplantation, and death (P < 0.001). Myocarditis represents a life-threatening disease with an overall mortality of 4.6% in this cohort. The fulminant form more often affected the youngest, leading to significantly higher rate of MCS, transplantation, and mortality. MCS represents an important and life-saving therapeutic option in children with myocarditis with a weaning rate of 43%.

Clinical Presentation and Outcome in a Contemporary Cohort of Patients With Acute Myocarditis: Multicenter Lombardy Registry

BACKGROUND

There is controversy about the outcome of patients with acute myocarditis (AM), and data are lacking on how patients admitted with suspected AM are managed. We report characteristics, in-hospital management, and long-term outcome of patients with AM based on a retrospective multicenter registry from 19 Italian hospitals.

METHODS

A total of 684 patients with suspected AM and recent onset of symptoms (<30 days) were screened between May 2001 and February 2017. Patients >70 years of age and those >50 years of age without coronary angiography were excluded. The final study population comprised 443 patients (median age, 34 years; 19.4% female) with AM diagnosed by either endomyocardial biopsy or increased troponin plus edema and late gadolinium enhancement at cardiac magnetic resonance.

RESULTS

At presentation, 118 patients (26.6%) had left ventricular ejection fraction <50%, sustained ventricular arrhythmias, or a low cardiac output syndrome, whereas 325 (73.4%) had no such complications. Endomyocardial biopsy was performed in 56 of 443 (12.6%), and a baseline cardiac magnetic resonance was performed in 415 of 443 (93.7%). Cardiac mortality plus heart transplantation rates at 1 and 5 years were 3.0% and 4.1%. Cardiac mortality plus heart transplantation rates were 11.3% and 14.7% in patients with complicated presentation and 0% in uncomplicated cases (log-rank P<0.0001). Major AM-related cardiac events after the acute phase (postdischarge death and heart transplantation, sustained ventricular arrhythmias treated with electric shock or ablation, symptomatic heart failure needing device implantation) occurred in 2.8% at the 5-year follow-up, with a higher incidence in patients with complicated forms (10.8% versus 0% in uncomplicated AM; log-rank P<0.0001). β-Adrenoceptor blockers were the most frequently used medications both in complicated (61.9%) and in uncomplicated forms (53.8%; P=0.18). After a median time of 196 days, 200 patients had follow-up cardiac magnetic resonance, and 8 of 55 (14.5%) with complications at presentation had left ventricular ejection fraction <50% compared with 1 of 145 (0.7%) of those with uncomplicated presentation.

CONCLUSIONS

In this contemporary study, overall serious adverse events after AM were lower than previously reported. However, patients with left ventricular ejection fraction <50%, ventricular arrhythmias, or low cardiac output syndrome at presentation were at higher risk compared with uncomplicated cases that had a benign prognosis and low risk of subsequent left ventricular systolic dysfunction.

Clinical Presentation and Laboratory Findings in Men Versus Women with Myocarditis

Objectives: Understanding sex differences in myocarditis is crucial to improve clinical care. We sought to investigate sex differences focusing on clinical presentation and laboratory parameters. Methods: From 2011 to 2018, 77 patients were diagnosed with myocarditis according to European Society of Cardiology (ESC) criteria with available clinical, laboratory, and cardiac magnetic resonance imaging data. First, we investigated sex differences of clinical and laboratory parameters in the entire cohort of 77 patients. Second, we focused on patients with acute myocarditis (n = 51) defined as recent symptom onset (≤10 days). Results: Myocarditis was present in 63 men (82%) and 14 women (18%). While men most frequently presented with chest pain (78%), a considerable amount of women presented with dyspnea as the only symptom (40%). Within the entire cohort, only creatinine kinase (CK) was higher in men versus women (364 ± 286 vs. 147 ± 148 U/L, p = 0.007), while in patients with acute myocarditis both CK and myoglobin (Mb) were higher in men versus women (CK: 327 ± 223 vs. 112 ± 65 U/L, p = 0.004 and Mb: 111 ± 126 vs. 25 ± 29 μg/L, p = 0.04). No sex differences were found for high-sensitivity troponin T, C-reactive protein, and NT-probrain natriuretic peptide. Conclusions: This is the first study reporting sex differences in clinical presentation and routine laboratory parameters in myocarditis. While clinical presentation appeared to be subtle in women with dyspnea being the only presenting symptom of myocarditis in a considerable part, men typically complained of chest pain. Similarly to observations in myocardial infarction, atypical symptoms and underdiagnosis may be a cause for under-representation of women in cohorts of myocarditis.

Early Detection of Localized Immunity in Experimental Autoimmune Myocarditis Using [99mTc]Fucoidan SPECT

PURPOSE

The aim of the study was to evaluate the ability of technetium-99m-fucoidan ([^99mTc]fucoidan), a molecular imaging agent specific for selectins, in the assessment of early localized immunity in a rat model of experimental autoimmune myocarditis (EAM).

PROCEDURES

EAM was induced in Lewis rats and troponin T; brain natriuretic peptide (BNP) and anti-myosin antibodies were measured in plasma. Separately, [^99mTc]fucoidan single-photon emission computed tomography (SPECT)/x-ray computed tomography (CT) was performed in the very early phase of myocarditis at 10, 15, and 21 days after immunization. Then, hearts were collected and used for autoradiography, well counting, histology, and flow cytometry analysis.

RESULTS

The EAM acute phase is characterized by extensive myocardial necrosis, release of troponin and BNP, and pericardial effusion. [^99mTc]Fucoidan uptake was significantly increased in EAM compared with controls starting from D15. There was a close relationship between uptake of the tracer and myocardial content in CD45+, CD8+, CD11b+, and CD31+ cells.

CONCLUSIONS

[^99mTc]Fucoidan SPECT/CT accurately diagnosed the autoimmune attack in the early steps of EAM and could be used to monitor disease evolution and therapy efficiency.

Acute Myocarditis Presenting as Acute Coronary Syndrome

A 50-year-old male presented to the hospital with an approximate three-week history of nausea, fever, and back pain. Upon initial evaluation he had an electrocardiogram with ischemic changes and initial labs significant for a troponin of >25.0 ng/ml (<0.30 ng/ml), pro b-type natriuretic peptide (proBNP) of 9884 pg/ml (<125 pg/ml), and a lactic acid of 4.3 mmol/L (0.5-1.9 mmol/L). There was a concern for an acute coronary syndrome presenting as cardiogenic shock, but the patient was unable to tolerate left heart catheterization. He had a rapid clinical decline and despite all efforts, he passed away. The initial cause of death was thought to be due to an acute myocardial infarction, however, autopsy results were consistent with acute myocarditis. This case highlights the presentation of acute myocarditis as an acute coronary syndrome with complete heart block. 

Role of intravenous immunoglobulin therapy in the survival rate of pediatric patients with acute myocarditis: A systematic review and meta-analysis

The treatment of pediatric myocarditis is controversial, and the benefits of intravenous immunoglobulin (IVIG) are inconclusive due to limited data. We searched studies from PubMed, MEDLINE, Embase, and Cochrane Library databases since establishment until October 1st, 2018. Thirteen studies met the inclusion criteria. We included a total of 812 patients with IVIG treatment and 592 patients without IVIG treatment. The meta-analysis showed that the survival rate in the IVIG group was higher than that in the non-IVIG group (odds ratio = 2.133, 95% confidence interval (CI): 1.32-3.43, p = 0.002). There was moderate statistical heterogeneity among the included studies (I² = 35%, p = 0.102). However, after adjustment using Duval and Tweedie's trim and fill method, the point estimate of the overall effect size was 1.40 (95% CI 0.83, 2.35), which became insignificant. Moreover, the meta-regression revealed that age (coefficient = -0.191, 95% CI (-0.398, 0.015), p = 0.069) and gender (coefficient = 0.347, 95% CI (-7.586, 8.279), p = 0.93) were not significantly related to the survival rate. This meta-analysis showed that IVIG treatment was not associated with better survival. The use of IVIG therapy in acute myocarditis in children cannot be routinely recommended based on current evidence. Further prospective and randomized controlled studies are needed to elucidate the effects of IVIG treatment.

Successful Bridge-to-Recovery Treatment in a Young Patient with Fulminant Eosinophilic Myocarditis: Roles of a Percutaneous Ventricular Assist Device and Endomyocardial Biopsy

Eosinophilic myocarditis (EM) is a rare condition characterized by myocardial eosinophilic infiltration due to various underlying etiologies. The patient with EM may benefit from appropriate use of mechanical circulatory support (MCS) that acts as a bridge to myocardial recovery in response to effective immunosuppressive therapy. A 16-year-old boy presented with cardiogenic shock due to fulminant myocarditis, for which a percutaneous ventricular assist device (PVAD) was immediately inserted. Based on the histological diagnosis of EM, immunosuppressive therapy was immediately commenced, leading to improvement of left-ventricular ejection fraction (27% to 47%). The PVAD was successfully removed on day 7. Cardiac magnetic resonance imaging and dual-tracer myocardial scintigraphy suggested limited extent of irreversible myocardial damage. For fulminant EM, the short-term use of PVAD, together with immunosuppressive therapy guided by an immediate histological investigation, may be an effective bridging strategy to myocardial recovery.

Outcome for children following admission to hospital with a first episode of heart failure, due to heart muscle disease, in the ventricular assist device (VAD) era

AIMS

Most reports on the outcome of children who present with heart failure, due to heart muscle disease, are from an era when ventricular assist devices were not available. This study provides outcome data for the current era where prolonged circulatory support can be considered for most children.

METHODS & RESULTS

Data was retrieved on 100 consecutive children, who presented between 2010 - 2016, with a first diagnosis of unexplained heart failure. Hospital outcome was classified as either death, transplantation, recovery of function or persistent heart failure. Median age at presentation was 24 months and 58% were < 5 years old. Hospital mortality was 12% and 59% received a heart transplant. Most, 79%, of the transplants were carried out on patients with a device. Recovery of function was observed in 18% and 10% stabilised on oral therapy. Eighty-four percent of the deaths occurred in the <5 year old group. Shorter duration of support was associated with survival (34 days in survivors versus 106 in non-survivors, p = 0.01) and 72% were on an assist device at time of death.

CONCLUSION

Heart failure in children who require referral to a transplant unit is a serious illness with a high chance of either transplantation or death. Modifications in assist devices will be required to improve safety, especially for children < 5 years old where the donor wait may be prolonged. The identification of children who may recover function requires further study.

Myocarditis and cardiomyopathy

PURPOSE OF REVIEW

The aim of this study is to summarize the literature describing the pathogenesis, diagnosis and management of cardiomyopathy related to myocarditis.

RECENT FINDINGS

Myocarditis has a variety of causes and a heterogeneous clinical presentation with potentially life-threatening complications. About one-third of patients will develop a dilated cardiomyopathy and the pathogenesis is a multiphase, mutlicompartment process that involves immune activation, including innate immune system triggered proinflammatory cytokines and autoantibodies. In recent years, diagnosis has been aided by advancements in cardiac MRI, and in particular T1 and T2 mapping sequences. In certain clinical situations, endomyocardial biopsy (EMB) should be performed, with consideration of left ventricular sampling, for an accurate diagnosis that may aid treatment and prognostication.

SUMMARY

Although overall myocarditis accounts for a minority of cardiomyopathy and heart failure presentations, the clinical presentation is variable and the pathophysiology of myocardial damage is unique. Cardiac MRI has significantly improved diagnostic abilities, but endomyocardial biopsy remains the gold standard. However, current treatment strategies are still focused on routine heart failure pharmacotherapies and supportive care or cardiac transplantation/mechanical support for those with end-stage heart failure.

Myocarditis in Humans and in Experimental Animal Models

Myocarditis is defined as an inflammation of the cardiac muscle. In humans, various infectious and non-infectious triggers induce myocarditis with a broad spectrum of histological presentations and clinical symptoms of the disease. Myocarditis often resolves spontaneously, but some patients develop heart failure and require organ transplantation. The need to understand cellular and molecular mechanisms of inflammatory heart diseases led to the development of mouse models for experimental myocarditis. It has been shown that pathogenic agents inducing myocarditis in humans can often trigger the disease in mice. Due to multiple etiologies of inflammatory heart diseases in humans, a number of different experimental approaches have been developed to induce myocarditis in mice. Accordingly, experimental myocarditis in mice can be induced by infection with cardiotropic agents, such as coxsackievirus B3 and protozoan parasite Trypanosoma cruzi or by activating autoimmune responses against heart-specific antigens. In certain models, myocarditis is followed by the phenotype of dilated cardiomyopathy and the end stage of heart failure. This review describes the most commonly used mouse models of experimental myocarditis with a focus on the role of the innate and adaptive immune systems in induction and progression of the disease. The review discusses also advantages and limitations of individual mouse models in the context of the clinical manifestation and the course of the disease in humans. Finally, animal-free alternatives in myocarditis research are outlined.

The Clinical Potential of Impella 5.0 Support in the Treatment of Recurrent Fulminant Viral Myocarditis with Profound Cardiogenic Shock

We herein report the clinical potential of Impella 5.0 support, which is a catheter-mounted micro-axial left ventricular support device, in a 39-year-old man with recurrent fulminant viral myocarditis complicated with profound cardiogenic shock despite inotropic infusion and an intra-aortic balloon pumping. Switching from these therapies to the Impella 5.0 device provided sufficient systemic perfusion with well-controlled left ventricular diastolic properties to facilitate a prompt recovery from profound cardiogenic shock. The patient was uneventfully discharged on the 27th hospital day. Given its effect of cardiac protection with sufficient systemic perfusion, the Impella device should be considered the first-line therapy for the treatment of fulminant myocarditis complicated with cardiogenic shock.

Immunosuppressive Therapy Improves Both Short- and Long-Term Prognosis in Patients With Virus-Negative Nonfulminant Inflammatory Cardiomyopathy

BACKGROUND

Inflammatory cardiomyopathy (infl-CMP) is characterized by increased cardiac inflammation in the absence of viruses, ischemia, valvular disease, or other apparent causes. Studies addressing the efficacy of immunosuppressive therapy in patients with infl-CMP are sparse. This study retrospectively investigates whether immunosuppressive agents on top of heart failure therapy according to current guidelines improves cardiac function and long-term outcome in patients with infl-CMP.

METHODS AND RESULTS

Within the Innsbruck and Maastricht Cardiomyopathy Registry, a total of 209 patients fulfilled the criteria for infl-CMP using endomyocardial biopsy (≥14 infiltrating inflammatory cells/mm²). A total of 110 (53%) patients received immunosuppressive therapy and 99 (47%) did not. To correct for potential selection bias, 1:1 propensity score matching was used on all significant baseline parameters, resulting in a total of 90 patients per group. Baseline characteristics did not significantly differ between both patient groups, reflecting optimal propensity score matching. After a median follow-up of 31 (15-47) months, immunosuppressive therapy resulted in an improved long-term outcome (eg, heart transplantation-free survival) as compared with standard heart failure therapy alone (Log-rank P=0.043; hazard ratio, 0.34 [95% CI, 0.17-0.92]) and in a significant larger increase of left ventricular ejection fraction after a mean of 12 months follow-up, as compared with patients receiving standard heart failure treatment only (12.2% versus 7.3%, respectively; P=0.036).

CONCLUSIONS

To conclude, this study suggests that immunosuppressive therapy in infl-CMP patients results in an improved heart transplantation-free survival as compared with standard heart failure therapy alone, underscoring the urgent need for a large prospective multicenter trial.

Trends in the Incidence of In-Hospital Mortality, Cardiogenic Shock, and Utilization of Mechanical Circulatory Support Devices in Myocarditis (Analysis of National Inpatient Sample Data, 2005-2014)

BACKGROUND

Myocarditis may be associated with hemodynamic instability and portends a poor prognosis when associated with cardiogenic shock (CS). There are limited data available on the incidence of in-hospital mortality, CS, and utilization of mechanical circulatory support (MCS) devices in these patients.

METHODS

We queried the 2005-2014 National Inpatient Sample databases to identify all patients aged >18 years with myocarditis in the United States.

RESULTS

The number of reported cases of myocarditis per 1 million gradually increased from 95 in 2005 to 144 in 2014 (Pfor trend <.01). The trend and incidence of endomyocardial biopsy remained the same despite the increase in clinical diagnosis. Overall, in-hospital mortality was 4.43% of total admissions without a change in overall trend over the study period. We also observed a significant increase in the incidence of CS from 6.94% in 2005 to 11.99% in 2014 (Pfor trend <.01). There was a parallel increase in the utilization of advanced MCS devices during the same time period such as extracorporeal membrane oxygenation or percutaneous cardiopulmonary support (0.32% in 2005 to 2.1% in 2014; P< .01) and percutaneous ventricular assist devices such as Impella/tandem heart (0.176% in 2005 to 1.75% in 2014; P< .01).

CONCLUSION

Although the incidence of myocarditis has increased in the last decade, the in-hospital mortality has remained the same despite increases in the incidence of CS, possibly reflecting the benefits of increased usage of advanced MCS devices. We noted that increasing age, presence of multiple comorbidities and CS were associated with an increase in in-patient mortality.

Analysis of clinical parameters and echocardiography as predictors of fatal pediatric myocarditis

Pediatric myocarditis symptoms can be mild or as extreme as sudden cardiac arrest. Early identification of the severity of illness and timely provision of critical care is helpful; however, the risk factors associated with mortality remain unclear and controversial. We undertook a retrospective review of the medical records of pediatric patients with myocarditis in a tertiary care referral hospital for over 12 years to identify the predictive factors of mortality. Demographics, presentation, laboratory test results, echocardiography findings, and treatment outcomes were obtained. Regression analyses revealed the clinical parameters for predicting mortality. During the 12-year period, 94 patients with myocarditis were included. Of these, 16 (17%) patients died, with 12 succumbing in the first 72 hours after admission. Fatal cases more commonly presented with arrhythmia, hypotension, acidosis, gastrointestinal symptoms, decreased left ventricular ejection fraction, and elevated isoenzyme of creatine kinase and troponin I levels than nonfatal cases. In multivariate analysis, troponin I > 45 ng/mL and left ventricular ejection fraction < 42% were significantly associated with mortality. Pediatric myocarditis had a high mortality rate, much of which was concentrated in the first 72 hours after hospitalization. Children with very high troponin levels or reduced ejection fraction in the first 24 hours were at higher risk of mortality, and targeting these individuals for more intensive therapies may be warranted.

A life support-based comprehensive treatment regimen dramatically lowers the in-hospital mortality of patients with fulminant myocarditis: a multiple center study

Fulminant myocarditis (FM) has unacceptable high mortality. This study aimed to evaluate the therapeutic efficacy of a life support-based comprehensive treatment regimen (LSBCTR), a completely novel treatment regimen, for FM. A total of 169 FM patients recruited from January 2008 to December 2018 were divided into two groups: patients receiving LSBCTR (81 cases), which includes (i) mechanical life support (positive pressure respiration, intra-aortic balloon pump with or without extracorporeal membrane oxygenation), (ii) immunomodulation therapy using sufficient doses of glucocorticoids and immunoglobulins, and (iii) application of neuraminidase inhibitors, and those receiving conventional treatment (88 cases). The endpoints were in-hospital death and heart-transplantation. Of all the population, 44 patients (26.0%) died in hospitals. In-hospital mortality was 3.7% (3/81) for LSBCTR group and 46.6% (41/88) for traditional treatment (P<0.001). Early application of LSBCTR, mechanical life support, neuraminidase inhibitors, and immunomodulation therapy significantly contributed to reduction in in-hospital mortality. This study describes a novel treatment regimen for FM patients that dramatically reduces in-hospital mortality. Its generalization and clinical application will efficiently save lives although further optimization is needed. This study offers an insight that virus infection induced inflammatory waterfall results in cardiac injury and cardiogenic shock and is the therapeutic target.

Coxsackie B2 Virus Infection Causing Multiorgan Failure and Cardiogenic Shock in a 42-Year-Old Man

Infections from coxsackie B2 viruses often cause viral myocarditis and, only rarely, multisystem organ impairment. We present the unusual case of a 42-year-old man in whom coxsackie B2 virus infection caused multiorgan infection, necessitating distal pancreatectomy, splenectomy, renal dialysis, and venoarterial extracorporeal membrane oxygenation with mechanical ventilation. In addition, the patient had a rapid-eye-movement sleep-related conduction abnormality that caused frequent sinus pauses of longer than 10 s, presumably due to myocarditis from the coxsackievirus infection. He recovered after permanent pacemaker placement and was discharged from the hospital. We discuss our aggressive supportive care and the few other reports of multiorgan impairment from coxsackieviruses.

Long-term and clinical profile of heart failure with recovered ejection fraction in a non-tertiary hospital

INTRODUCTION

Heart failure (HF) with recovered ejection fraction (EF) is emerging as a different HF subtype. There is little information about his clinical profile in hospitals that are not a reference.

METHODS

We analysed characteristics and prognosis in patients with recovered HF followed prospectively in the HF Unit of a non-tertiary hospital.

RESULTS

A total of 431 patients with HF with reduced EF were followed (median 50 months, 79.3% males, mean age 70.3±12.2years). Of the patients, 26.9% (N 116) recovered EF, mainly in the first year of follow-up (76.7%). Compared with patients that did not recovered EF in the follow-up, they were younger, rate of ischemic origin of cardiomyopathy was less frequent and presented less comorbidity. Mortality was lower in patients with recovered HF (survival median of 85.2±2.1 vs. 74.2±1.9 months [log-rank χ² 11.5, P=0.001], hazard ratio 0.37, 95% confidence interval [CI]: 0.21-0.67, P=0.002). Aetiology of deaths was not mainly secondary to HF. Younger age of 68 years (odds ratio [OR] 0-98, 95% CI: 0.96-0,99; P=0.025), ischemic origin (OR 1.12, 95% CI: 1.01-1.21; P=0.003) and use of aldosterone antagonists (OR 1.89, 95% CI: 1.09-3.26; P=0.023) were the variables independently associated to normalisation of EF.

CONCLUSION

HF with recovered EF is a frequent phenomenon. It has a more favourable clinical course, prognosis and basal characteristics than HF with persistent reduced EF. Further studies are needed to identify natural history and optimal medications for HF-recovered patients.

Diagnostic Dilemmas and Management of Fulminant Myocarditis

Myocarditis is commonly a diagnosis of exclusion. We report a case of fulminant myocarditis in a patient with cardiogenic shock in whom the initial diagnosis was unclear. Early supportive care including extracorporeal membrane oxygenation and intraaortic balloon pump were instituted. Complete recovery of cardiac function was achieved. This case highlights the difficulty in diagnosing myocarditis and the benefits of early intensive support.

KSHF Guidelines for the Management of Acute Heart Failure: Part III. Specific Management of Acute Heart Failure According to the Etiology and Co-morbidity

The prevalence of heart failure (HF) is on the rise due to the aging of society. Furthermore, the continuous progress and widespread adoption of screening and diagnostic strategies have led to an increase in the detection rate of HF, effectively increasing the number of patients requiring monitoring and treatment. Because HF is associated with substantial rates of mortality and morbidity, as well as high socioeconomic burden, there is an increasing need for developing specific guidelines for HF management. The Korean guidelines for the diagnosis and management of chronic heart failure (CHF) were introduced in March 2016. However, CHF and acute heart failure (AHF) represent distinct disease entities. Here, we introduce the Korean guidelines for the management of AHF with reduced or preserved ejection fraction. Part III of this guideline covers management strategies optimized according to the etiology of AHF and the presence of co-morbidities.

Chinese society of cardiology expert consensus statement on the diagnosis and treatment of adult fulminant myocarditis

Fulminant myocarditis is primarily caused by infection with any number of a variety of viruses. It arises quickly, progresses rapidly, and may lead to severe heart failure or circulatory failure presenting as rapid-onset hypotension and cardiogenic shock, with mortality rates as high as 50%–70%. Most importantly, there are no treatment options, guidelines or an expert consensus statement. Here, we provide the first expert consensus, the Chinese Society of Cardiology Expert Consensus Statement on the Diagnosis and Treatment of Fulminant Myocarditis, based on data from our recent clinical trial (NCT03268642). In this statement, we describe the clinical features and diagnostic criteria of fulminant myocarditis, and importantly, for the first time, we describe a new treatment regimen termed life support-based comprehensive treatment regimen. The core content of this treatment regimen includes (i) mechanical life support (applications of mechanical respirators and circulatory support systems, including intraaortic balloon pump and extracorporeal membrane oxygenation, (ii) immunological modulation by using sufficient doses of glucocorticoid, immunoglobulin and (iii) antiviral reagents using neuraminidase inhibitor. The proper application of this treatment regimen may and has helped to save the lives of many patients with fulminant myocarditis.

An Out-of-Season Case of Coxsackie B Myocarditis with Severe Rhabdomyolysis

A 21-year-old woman was found to have fulminant myocarditis as a result of Coxsackie B infection (a virus shown to exhibit summer-fall seasonality) in mid-December. In this case report, seasonality of enteroviruses is examined, as well as additional factors which may contribute to sporadic cases during winter months. The case report also discusses clinical criteria for endomyocardial biopsy, utility of PCR vs. antibody serological tests, coinfection with multiple serotypes, and rhabdomyolysis in Coxsackie B.

Acute and Fulminant Myocarditis: a Pragmatic Clinical Approach to Diagnosis and Treatment

PURPOSE OF REVIEW

To review the clinical features of acute myocarditis, including its fulminant presentation, and present a pragmatic approach to the diagnosis and treatment, considering indications of American and European Scientific Statements and recent data derived by large contemporary registries.

RECENT FINDINGS

Patients presenting with acute uncomplicated myocarditis (i.e., without left ventricular dysfunction, heart failure, or ventricular arrhythmias) have a favorable short- and long-term prognosis: these findings do not support the indication to endomyocardial biopsy in this clinical scenario. Conversely, patients with complicated presentations, especially those with fulminant myocarditis, require an aggressive and comprehensive management, including endomyocardial biopsy and availability of advanced therapies for circulatory support. Although several immunomodulatory or immunosuppressive therapies have been studied and are actually prescribed in the real-world practice, their effectiveness has not been clearly demonstrated. Patients with specific histological subtypes of acute myocarditis (i.e., giant cell and eosinophilic myocarditis) or those affected by sarcoidosis or systemic autoimmune disorders seem to benefit most from immunosuppression. On the other hand, no clear evidence supports the use of immunosuppressive agents in patients with lymphocytic acute myocarditis, even though small series suggest a potential benefit. Acute myocarditis is a heterogeneous condition with distinct pathophysiological pathways. Further research is mandatory to identify factors and mechanisms that may trigger/maintain or counteract/repair the myocardial damage, in order to provide a rational for future evidence-based treatment of patients affected by this condition.

Potential for and timing of recovery in children with dilated cardiomyopathy

OBJECTIVE

Understanding the clinical course and time-frame for recovery is helpful to guide management and counselling following a diagnosis of Dilated Cardiomyopathy (DCM). We aimed to document outcomes and time to recovery for a cohort of patients with a dilated cardiomyopathy phenotype.

METHODS

An observational cohort methodology was used to collect retrospective data from the departmental database for those identified with DCM. Data relating to mode of presentation, echocardiographic parameters, clinical management and outcome were collated and analysed. Predictors and time-scale for recovery were investigated and reported.

RESULTS

209 new referrals were included within the time frame. 82 children median age 1.0years (IQR 3.4) required intensive care (ICU) and their survival without death or transplant was 51% to one year and 45% to five years. 127 children presented to the pediatric heart failure clinic. Excluding 58 with neuromuscular disease, median age was 4.1years (IQR 11.3) & survival without death or transplant 85% to 1year and 50% to 5years. NT-proBNP normalized in survivors before echocardiographic parameters. Predictors of recovery included younger age, female sex and smaller left ventricular end diastolic Z score on echocardiogram at presentation.

CONCLUSION

Transplant-free survival to one year is significantly better for patients presenting to clinic, but longer-term survival is better amongst those presenting to ICU due to a late attrition in those with less severe heart failure at presentation. Falling NT-proBNP is the earliest marker of recovery. Recovery of cardiac function remains possible up to three years from presentation.

A Fatal Case of Influenza B Myocarditis with Cardiac Tamponade

Background

Influenza B is generally regarded as a less severe counterpart to influenza A, typically causing mild upper respiratory symptoms. Myocardial involvement with influenza B is a rare complication, better described in children than adults. However, when it occurs, it can lead to profound myocarditis with progression to shock requiring aggressive supportive care.

Case Presentation

We present a case of cardiac tamponade in the setting of influenza B infection in a previously healthy 57-year-old woman, with progression to refractory shock and death. Autopsy revealed myocardial necrosis with infiltration of CD3+ lymphocytes, and little evidence of viral pneumonia.

Conclusions

Myocarditis is a rare complication of influenza B in adults, and subsequent pericardial effusion with tamponade physiology is a previously unreported event in an otherwise healthy adult without other medical comorbidities. While rare, this is a serious and potentially fatal complication that clinicians should be aware of when evaluating a patient with suspected viral illness who is exhibiting shock physiology.

Clinical determinants of successful weaning from extracorporeal membrane oxygenation in patients with fulminant myocarditis

Aims

Patients with fulminant myocarditis (FM) often present with cardiogenic shock and require mechanical circulatory support, including extracorporeal membrane oxygenation (ECMO) and ventricular assist device (VAD) implantation. This study sought to clarify the determinants of successful weaning from ECMO in FM patients.

Methods and results

We studied 37 consecutive FM patients supported by ECMO as the initial form of mechanical circulatory support between January 1995 and December 2014 in our hospital. Twenty‐two (59%) patients were successfully weaned from ECMO, while 15 (41%) were not. There were significant differences in levels of peak creatine kinase and those of its MB isoform (CK‐MB), left ventricular posterior wall thickness (LVPWT), and prevalence of cardiac rhythm disturbances. Receiver operating characteristic curve analysis revealed that a peak CK‐MB level of 185 IU/L and LVPWT of 11 mm were the optimal cut‐off values for predicting successful weaning from ECMO (areas under the curve, 0.89 and 0.85, respectively). During the follow‐up [median 48 (interquartile range 8–147) months], 83% of FM patients who were weaned from ECMO survived, with preserved fractional shortening based on echocardiography. Of the 15 FM patients who were not weaned from ECMO, nine bridged to VAD, and only two were successfully weaned from VAD and survived.

Conclusions

These results indicate that myocardial injury, as evidenced by CK‐MB and LVPWT, and prolonged presence of cardiac rhythm disturbances are important clinical determinants of successful weaning from ECMO.

Lupus myocarditis: a single center experience and a comparative analysis of observational cohort studies

Background Lupus myocarditis (LM) is reported in 3-9% of patients with systemic lupus erythematosus (SLE) but limited evidence exists regarding optimal treatment and prognosis. This study aims to describe LM in a defined lupus cohort as compared with the existing literature. Patients and methods Patients with LM were identified from the University of Toronto Lupus Clinic database. Diagnosis was based on clinical manifestations and electrocardiographic, imaging, and biochemical criteria. Demographic, clinical, diagnostic and therapeutic variables and outcomes were collected in a standardized data retrieval form. A literature review was performed to identify cohort studies reporting on LM treatment and outcome. A comparative analysis was conducted between our patients and the combined cohort of the existing studies. Results Thirty patients were diagnosed with LM (prevalence 1.6%) and compared with a cumulative cohort of 117 patients from five distinct studies. No significant differences were found regarding the age at diagnosis (32.6 ± 13.4 years) and SLE duration (2.5 years median). Concomitant lupus activity from other organ systems was observed in 97% of the patients. Chest pain was more frequently reported in our cohort whereas dyspnea was more prominent in the other studies. Diagnostic criteria were similar across studies. Therapeutic approach was comparable and consisted of glucocorticosteroids (96.6%) and immunosuppressives (70%). Mortality was approximately 20% whereas another 20% of the patients achieved partial and 60% complete recovery. Conclusions LM usually occurs early in the disease course and in the context of generalized lupus activity. Despite aggressive therapy, approximately 40% of the patients died or had residual heart damage.

Fulminant myocarditis: Characteristics, treatment, and outcomes

Myocarditis is an inflammatory disease of the myocardium with a broad spectrum of clinical presentations, ranging from mild symptoms to severe heart failure. The course of patients with myocarditis is heterogeneous, varying from partial or full clinical recovery in few days to advanced low cardiac output syndrome requiring mechanical circulatory support or heart transplantation. Fulminant myocarditis (FM) is a peculiar clinical condition and is an acute form of myocarditis, whose main characteristic is a rapidly progressive clinical course with the need for hemodynamic support. Despite the common medical belief of the past decades, recent comprehensive data, including a recent registry that compared FM with acute non-FM, highlighted that FM has a poor inhospital outcome, often requires advanced hemodynamic support, and may result in residual left ventricular dysfunction in survivors. This review aimed to provide an updated practical definition of FM, including essentials in the diagnosis and management of the disease. Finally, the outcome of FM was critically revised according to the current published registries focusing on the topic.

Case Report: III° atrioventricular block due to fulminant myocarditis managed with non-invasive transcutaneous pacing

Fulminant myocarditis is a life-threatening clinical condition. It is the inflammation of myocardium leading to acute heart failure, cardiogenic shock and cardiac arrhythmias. Incidence of fulminant myocarditis is low and mortality is high. Most grievous complications of fulminant myocarditis is mainly cardiac arrhythmias; if there is delay on active management of the patient, it may be fatal. Here, we describe a case of III° atrioventricular block due to fulminant myocarditis that was managed with non-invasive transcutaneous cardiac pacing in the absence of ECMO. The non-invasive transcutaneous pacemaker is a safe, effective and convenient device to revert arrhythmias.