Acute viral myocarditis: role of immunosuppression: a prospective randomised study

Rare case of subacute herpetic myocarditis

Viruses represent the main cause, especially in developed countries. Coxsackie and echoviruses are the most common cardiotropic viruses causing myocarditis. Herpes simplex virus-induced myocarditis is uncommon, and few cases of Herpes simplex virus (HSV) type II have been reported to date. This article presents a rare case of subacute herpetic myocarditis in a 35-year-old male patient.

Leitlinie Myokarditis der Deutschen Gesellschaft für Pädiatrische Kardiologie

This consensus statement presents updated recommendations on diagnosis and treatment of myocarditis in childhood.

Corticosteroid in anti-inflammatory treatment of pediatric acute myocarditis: a systematic review and meta-analysis

BACKGROUND

To evaluate the efficacy of corticosteroids in anti-inflammatory treatment of pediatric acute myocarditis.

METHODS

We searched PubMed, Embase and Cochrane library and included studies before October 2022 for clinical trials, observational studies and retrospective studies which reported on children with acute myocarditis treated with corticosteroid anti-inflammatory therapy. The quality of the clinical trials was assessed by Jadad score as an exclusion criterion.

RESULTS

This systematic review included 6 studies involving 604 pediatric patients with acute myocarditis. Corticosteroid therapy was not associated with reduced risk of mortality due to acute myocarditis (P = 0.53; RR = 0.87; 95% CI = 0.58 to 1.33) compared to anti-failure treatment. There was a significant improvement in pediatric patients' left ventricular function measured by left ventricular ejection fraction in the group on corticosteroid anti-inflammatory treatment (P = 0.0009; MD = 11.93%; 95% CI = 4.87% to 18.99%). No conclusion can be drawn due to the high heterogeneity in meta-analyses of risk of getting to a clinical endpoint (death or heart transplantation) and changes in left ventricular end-diastolic diameter (LVEDD).

CONCLUSIONS

Corticosteroid anti-inflammatory therapy in pediatric acute myocarditis patients showed no significant improvement in reducing the risk of mortality, but showed significant improvement in LVEF.

Treating Pediatric Myocarditis with High Dose Steroids and Immunoglobulin

There is considerable variability in practice among pediatric centers for treatment of myocarditis. We report outcomes using high dose steroids in conjunction with IVIG. This is a single center retrospective study of children < 21 years of age diagnosed with myocarditis and treated with high dose steroids and IVIG from January 2004-April 2021. Diagnostic criteria for myocarditis included positive endomyocardial biopsy, cardiac magnetic resonance (CMR) imaging meeting Lake Louise criteria, or strictly defined clinical diagnosis. Forty patients met inclusion criteria. Median age at diagnosis was 11.6 years (0.7-14.6). Diagnosis was made clinically in 70% of cases (N = 28), by CMR in 12.5% (N = 5) and by biopsy in 17.5% (N = 7). Median ejection fraction (EF) at diagnosis was 35% (IQR 24-48). Median duration of IV steroids was 7 days (IQR 4-12) followed by an oral taper. Median cumulative dose of IV immunoglobulin (IVIG) was 2 g/kg. There were no serious secondary bacterial infections after steroid initiation. Ten patients (25%) required mechanical circulatory support. Overall transplant free survival was 92.5% with median follow-up of 1 year (IQR 0-6 years). Six patients required re-admission for cardiovascular reasons. By 3 months from diagnosis, 70% of patients regained normal left ventricular function. High dose steroids in conjunction with IVIG to treat acute myocarditis can be safe without significant infections or long-term side effects. Our cohort had excellent recovery of ventricular function and survival without transplant. Prospective comparison of a combination of high dose steroids with IVIG versus other therapies is needed.

Clinical characteristics and outcome of biopsy-proven myocarditis in children - Results of the German prospective multicentre registry "MYKKE"

BACKGROUND

Heart failure (HF) due to myocarditis might not respond in the same way to standard therapy as HF due to other aetiologies. The aim of this study was to investigate the value of endomyocardial biopsies (EMB) for clinical decision-making and its relation to the outcome of paediatric patients with myocarditis.

METHODS

Clinical and EMB data of children with myocarditis collected for the MYKKE-registry between 2013 and 2020 from 23 centres were analysed. EMB studies included histology, immunohistology, and molecular pathology. The occurrence of major adverse cardiac events (MACE) including mechanical circulatory support (MCS), heart transplantation, and/or death was defined as a combined endpoint.

RESULTS

Myocarditis was diagnosed in 209/260 patients: 64% healing/chronic lymphocytic myocarditis, 23% acute lymphocytic myocarditis (AM), 14% healed myocarditis, no giant cell myocarditis. The median age was 12.8 (1.4-15.9) years. Time from symptom-onset to EMB was 11.0 (4.0-29.0) days. Children with AM and high amounts of mononuclear cell infiltrates were significantly younger with signs of HF compared to those with healing/chronic or healed myocarditis. Myocardial viral DNA/RNA detection had no significant effect on outcome. The worst event-free survival was seen in patients with healing/chronic myocarditis (24%), followed by acute (31%) and healed myocarditis (58%, p = 0.294). A weaning rate of 64% from MCS was found in AM.

CONCLUSIONS

EMB provides important information on the type and stage of myocardial inflammation and supports further decision-making. Children with fulminant clinical presentation, high amounts of mononuclear cell infiltrates or healing/chronic inflammation and young age have the highest risk for MACE.

Comparison and Analysis on the Existing Single-Herbal Strategies against Viral Myocarditis

Purpose

Herbal medicine is one of crucial symbols of Chinese national medicine. Investigation on molecular responses of different herbal strategies against viral myocarditis is immeasurably conducive to targeting drug development in the current international absence of miracle treatment.

Methods

Literature retrieval platforms were applied in the collection of existing empirical evidences for viral myocarditis-related single-herbal strategies. SwissTargetPrediction, Metascape, and Discovery Studio coordinating with multidatabases investigated underlying target genes, interactive proteins, and docking molecules in turn.

Results

Six single-herbal medicines consisting of Huangqi (Hedysarum Multijugum Maxim), Yuganzi (Phyllanthi Fructus), Kushen (Sophorae Flavescentis Radix), Jianghuang (Curcumaelongae Rhizoma), Chaihu (Radix Bupleuri), and Jixueteng (Spatholobus Suberectus Dunn) meet the requirement. There were 11 overlapped and 73 unique natural components detected in these herbs. SLC6A2, SLC6A4, NOS2, PPARA, PPARG, ACHE, CYP2C19, CYP51A1, and CHRM2 were equally targeted by six herbs and identified as viral myocarditis-associated symbols. MCODE algorithm exposed the hub role of SRC and EGFR in strategies without Jianghuang. Subsequently, we learned intermolecular interactions of herbal components and their targeting heart-tissue-specific CHRM2, FABP3, TNNC1, TNNI3, TNNT2, and SCN5A and cardiac-myocytes-specific IL6, MMP1, and PLAT coupled with viral myocarditis. Ten interactive characteristics such as π-alkyl and van der Waals were modeled in which ARG111, LYS253, ILE114, and VAL11 on cardiac troponin (TNNC1-TNNI3-TNNT2) and ARG208, ASN106, and ALA258 on MMP1 fulfilled potential communicating anchor with ellagic acid, 5α, 9α-dihydroxymatrine, and leachianone g via hydrogen bond and hydrophobic interaction, respectively.

Conclusions

The comprehensive outcomes uncover differences and linkages between six herbs against viral myocarditis through component and target analysis, fostering development of drugs.

Efficacy of immunosuppressive therapy in myocarditis: A 30-year systematic review and meta analysis

AIMS

Myocarditis is an inflammation of the heart muscle, due to infectious, toxic or autoimmune causes. Literature reported controversial results in relation to the effect of immunosuppression (IS)/immunomodulation (IM). We aimed at assessing the effect of IS/IM by meta analysis.

METHODS AND RESULTS

Using the P.R.I.S.M.A. approach, two researchers searched for relevant studies on PubMed, Embase, and the Central Registry of Controlled Trials of the Cochrane Library. Proposed MeSH terms were: "immunotherapy OR immune therapy OR immune modeling OR Immunosuppressive Agents" AND "combination OR combined with OR plus" AND "myocarditis OR cardiomyopathies OR inflammatory cardiomyopathy". The language was restricted to English. Reference lists of included articles and those relevant to the topic were hand searched for the identification of additional, potentially relevant articles. The cutoff date was from 1987 until 30th Nov 2019. Reported survival or mortality events or change of left ventricular ejection fraction (LVEF) after IS/IT were primary outcomes of the study; in addition, improvement of New York Heart Association class, follow-up biopsy (Bx) findings, viral genome clearance on Bx and recurrence of myocarditis were recorded if reported. Statistical analysis was conducted using Review Manager 5.3; 5452 studies were screened, of these 73 were assessed for eligibility, including 8 randomized control studies, 26 retrospective studies, 2 prospective studies and 1 case control study, 34 case reports and 2 case series. In prospective studies, the difference in mortality between the IS and control groups tended to be lower in the combined IS groups (12.5% vs. 18.2%) (95% CI of odds ratio 0.7(0.3, 1.64)) and the pooled difference of the increase of LVEF between the IS and control groups tended to be higher in the combined IS groups (95% CI 7.26 (-2.29, 16.81)). In retrospective studies, the difference of survival between the IS and control group was significantly in favor of IS (95%CI Hazard ratio 0.82(0.69, 0.96)).

CONCLUSIONS

A tailored IS may be considered in myocarditis, depending on the phase of the disease, and the type of underlying autoimmune or immune-mediated form.

In-hospital and post-discharge outcomes of pediatric acute myocarditis underwent after high-dose steroid or intravenous immunoglobulin therapy

Background

High-dose steroids and intravenous immunoglobulin (IVIG) are controversial treatments for pediatric patients with acute myocarditis. This study aimed to investigate their efficacies in the Taiwanese pediatric population.

Methods

This study evaluated 5563 acute myocarditis patients from the Taiwan’s National Health Insurance Research Database and identified 1542 pediatric patients hospitalized for acute myocarditis between January 1, 2001 and December 31, 2011. The exclusion criteria were age of > 11 years, associated cardiovascular comorbidities, autoimmune disease, malignancy before the index hospitalization, extracorporeal membrane oxygenation, intra-aortic balloon pumping, and dual therapy using IVIG and high-dose steroids.

Results

After 2:1 propensity score matching, we identified 208 subjects without steroid therapy and 104 subjects who received high-dose steroids. The mean age in that cohort was 2.6 ± 2.9 years, and high-dose steroid therapy had no significant effects on major in-hospital complications and post-discharge outcomes. After 2:1 propensity score matching, we identified 178 subjects without IVIG therapy and 89 subjects who received IVIG. The mean age in that cohort was 2.0 ± 2.1 years, and IVIG had no significant effects on the major outcomes.

Conclusions

The present study revealed that high-dose steroid or IVIG therapy had no significant effects on major in-hospital complications, late heart failure hospitalization, and long-term mortality.

Immunosuppressive Treatment for Myocarditis in the Pediatric Population: A Meta-Analysis

The use of immunosuppressants in the treatment of myocarditis in children remains controversial. The aim of this meta-analysis is to summarize the current empirical evidence for immunosuppressive treatment for myocarditis in the pediatric population. We searched PubMed, MEDLINE, and Embase for articles to identify studies analyzing the efficiency of immunosuppressive treatment in the pediatric population. Pooled estimates were generated using fixed- or random-effect models. Heterogeneity within studies was assessed using Cochran's Q and I ² statistics. Funnel plots and Begg's rank correlation method were constructed to evaluate publication bias. Sensitivity analyses were also conducted to evaluate the potential sources of heterogeneity. After a detailed screening of 159 studies, six separate studies were identified, with 181 patients in the immunosuppressive treatment group, and 199 in the conventional treatment group. The immunosuppressive treatment group showed a significant improvement in left ventricular ejection fraction (LVEF) [mean difference 1.10; 95% CI: 0.41, 1.79] and significantly decreased left ventricular end-diastolic dimension (LVEDD) [mean difference -0.77 mm, 95% CI: -1.35 to -0.20 mm] when compared to the conventional treatment group. Furthermore, the risk of death and heart transplant in conventional treatment was significantly higher than in the immunosuppressive treatment group [relative risk (RR): 4.74; 95% CI: 2.69, 8.35]. No significant heterogeneity across the studies was observed. There was no evidence of publication bias when assessed by Begg's test. Conclusions: There may be a possible benefit, in the short term, to the addition of immunosuppressive therapy in the management of myocarditis in the pediatric population. However, further prospective investigation is warranted to validate this finding.

Corticosteroids and Intravenous Immunoglobulin in Pediatric Myocarditis: A Meta-Analysis

Background: The efficacy of corticosteroids and intravenous immunoglobulin (IVIG) in pediatric myocarditis remains controversial. Objectives: The authors performed a meta-analysis to assess the therapeutic efficacy of corticosteroids and IVIG in children with myocarditis. Methods: We retrieved the trials on corticosteroids and IVIG therapy, respectively, in pediatric myocarditis from nine databases up to December 2018. Statistical analysis was performed using Review Manager 5.3. Results: Our analysis included 8 studies and 334 pediatric patients. The data demonstrated that children receiving corticosteroids showed no significant improvement on left ventricular ejection fraction (LVEF) from 1 to 8 month-follow-up (MD = 5.17%, 95% CI = -0.26% to 10.60%, P = 0.06), and no significant improvement in death or heart transplantation incidence at the end of follow-up (OR = 1.33, 95% CI = 0.27-6.70, P = 0.73). However, children receiving IVIG revealed a statistically remarkable increase in LVEF at a follow-up over the course of 6 months to 1 year (MD = 18.91%, 95% CI = 11.74-26.08%, P < 0.00001), and a decrease in death or heart transplantation at the end of follow-up (OR = 0.31, 95% CI = 0.12-0.75, P = 0.01). Further comparisons showed that the mortality and heart transplantation rate of children with myocarditis treated with IVIG were significantly lower than those with corticosteroid therapy (t' = 11.336, P < 0.001). Conclusions: IVIG might be beneficial to improve LVEF and survival for myocarditis in children. However, the present evidence does not support corticosteroids as superior to conventional therapy in children with myocarditis. Further randomized controlled trials with a larger sample size are required.

Age-Associated Changes in Estrogen Receptor Ratios Correlate with Increased Female Susceptibility to Coxsackievirus B3-Induced Myocarditis

Sexual bias is a hallmark in various diseases. This review evaluates sexual dimorphism in clinical and experimental coxsackievirus B3 (CVB3) myocarditis, and how sex bias in the experimental disease changes with increased age. Coxsackieviruses are major causes of viral myocarditis, an inflammation of the heart muscle, which is more frequent and severe in men than women. Young male mice infected with CVB3 develop heart-specific autoimmunity and severe myocarditis. Females infected during estrus (high estradiol) develop T-regulatory cells and when infected during diestrus (low estradiol) develop autoimmunity similar to males. During estrus, protection depends on estrogen receptor alpha (ERα), which promotes type I interferon, activation of natural killer/natural killer T cells and suppressor cell responses. Estrogen receptor beta has opposing effects to ERα and supports pro-inflammatory immunity. However, the sexual dimorphism of the disease is significantly ameliorated in aged animals when old females become as susceptible as males. This correlates to a selective loss of the ERα that is required for immunosuppression. Therefore, sex-associated hormones control susceptibility in the virus-mediated disease, but their impact can alter with the age and physiological stage of the individual.

Toward evidence-based diagnosis of myocarditis in children and adolescents: Rationale, design, and first baseline data of MYKKE, a multicenter registry and study platform

The aim of this registry is to provide data on age-related clinical features of suspected myocarditis and to create a study platform allowing for deriving diagnostic criteria and, at a later stage, testing therapeutic interventions in patients with myocarditis.

STUDY DESIGN AND RESULTS

After an initial 6-month pilot phase, MYKKE was opened in June 2014 as a prospective multicenter registry for patients from pediatric heart centers, university hospitals, and community hospitals with pediatric cardiology wards in Germany. Inclusion criteria consisted of age<18 years and hospitalization for suspected myocarditis as leading diagnosis at the discretion of the treating physician. By December 31, 2015, fifteen centers across Germany were actively participating and had enrolled 149 patients. Baseline data reveal 2 age peaks (<2 years, >12 years), show higher proportions of males, and document a high prevalence of severe disease courses in pediatric patients with suspected myocarditis. Severe clinical courses and early adverse events were more prevalent in younger patients and were related to severely impaired leftventricular ejection fraction at initial presentation.

SUMMARY

MYKKE represents a multicenter registry and research platform for children and adolescents with suspected myocarditis that achieve steady recruitment and generate a wide range of real-world data on clinical course, diagnostic workup, and treatment of this group of patients. The baseline data reveal the presence of 2 age peaks and provide important insights into the severity of disease in children with suspected myocarditis. In the future, MYKKE might facilitate interventional substudies by providing an established collaborating network using common diagnostic approaches.

Immunosuppressive treatment for myocarditis: a meta-analysis of randomized controlled trials

BACKGROUND

Immunosuppressive treatment for myocarditis is controversial. Several small-scale randomized controlled trials (RCTs) reported inconsistent outcomes for patients with myocarditis.

METHODS

We searched on the Medline, Embase, and Cochrane databases for articles in English language between January 1966 and May 2013, as well as on the China National Knowledge Internet (CNKI, 1979 to May 2012) and the Chinese Biomedical Literature Database (CBM, 1978 to May 2013) for articles in Chinese language. Statistical analysis was performed using Review Manager 5.0.

RESULTS

Nine articles were finally selected, in which 342 patients were in immunosuppressive treatment group and 267 patients in conventional treatment group. The immunosuppressive treatment group showed a significant improvement in left ventricular ejection fraction at both short-term (≤3 months) [difference: 0.08, 95% confidence interval (CI): 0.05-0.10) and long-term (difference: 0.10, 95% CI: 0.00-0.21)] follow-up. Moreover, left ventricular end-diastolic dimension decreased significantly in the immunosuppressive treatment group after short-term follow-up (difference: -1.85 mm, 95% CI: -3.18 to -0.52 mm), but a long-term beneficial effect was not sustained (difference: -5.79 mm, 95% CI: -15.30 to 3.72 mm). There was no difference, however, between the two groups in the rate of death or heart transplantation (odds ratio: 1.33, 95% CI: 0.77, 2.31).

CONCLUSION

Immunosuppressive treatment might be beneficial for improving left ventricular systolic function and remodeling in patients with myocarditis, which could be considered as a therapeutic alternative when optimal conventional therapy is not effective. More large RCTs, however, are required.

Clinical Outcomes in Pediatric Patients Hospitalized with Fulminant Myocarditis Requiring Extracorporeal Membrane Oxygenation: A Meta-analysis

We conducted a meta-analysis to provide the survival rates for pediatric patients hospitalized with fulminant myocarditis requiring ECMO. The literature search was conducted using Embase, PubMed, MEDLINE and Elsevier for studies published before April 1, 2016. We focus on survival rates for pediatric patients hospitalized with fulminant myocarditis requiring ECMO, and studies that reported only on adult patients were excluded. Summary of the survival rates was obtained using fixed-effect or random-effect meta-analysis which determined by I ². Six studies were included in the analysis, encompassing 172 patients. The minimum and maximum reported rates of survival to hospital discharge were 53.8 and 83.3%, respectively. The cumulative rate was 107/172. The calculated Cochran Q value was 3.73, which was not significant for heterogeneity (P = 0.588). The I ² value was 0%. The pooled estimate rate was 62.9% with a 95% confidence interval of 55.3-69.8%. In pediatric patients with cardiac failure who have failed conventional therapies in FM, venoarterial ECMO should be considered. In total, 62.9% of patients with FM and either cardiogenic shock and/or cardiac arrest survived to hospital discharge with ECMO.

MicroRNA-98 plays a critical role in experimental myocarditis

BACKGROUND AND AIMS

Myocarditis is inflammation in the heart; its pathogenesis is to be further investigated. Activities of micro RNAs (miR) are associated with immune inflammation. This study tests a hypothesis that miR-98 is involved in the development of myocarditis.

METHODS

BALB/c mice were immunized with cardiac α-myosin heavy chain peptides (MyHC-α) to induce myocarditis. The effects of miR-98 on regulation of interleukin (IL)-10 were assessed by real time RT-PCR.

RESULTS

Mice immunized with MyHC-α showed myocarditis and lower frequency of IL-10⁺ B cells (B10 cell) in the hearts. Expression of miR-98 was higher, IL-10 was lower, in B cells isolated from the mouse hearts with myocarditis, which was negatively correlated with each other. Exposure to tumor necrosis factor-α up regulated miR-98 expression in B cells. Over-expression of miR-98 suppressed IL-10 expression in B cells. Blocking miR-98 or adoptively transplanting B10 cells attenuated experimental myocarditis.

CONCLUSIONS

miR-98 suppresses IL-10 expression in B cells in the heart, which plays an important role in myocarditis. MiR-98 may be a therapeutic target in the treatment of myocarditis.

Myocarditis in Paediatric Patients: Unveiling the Progression to Dilated Cardiomyopathy and Heart Failure

Myocarditis is a challenging and potentially life-threatening disease associated with high morbidity in some paediatric patients, due to its ability to present as an acute and fulminant disease and to ultimately progress to dilated cardiomyopathy. It has been described as an inflammatory disease of the myocardium caused by diverse aetiologies. Viral infection is the most frequent cause of myocarditis in developed countries, but bacterial and protozoal infections or drug hypersensitivity may also be causative agents. The prompt diagnosis in paediatric patients is difficult, as the spectrum of clinical manifestation can range from no myocardial dysfunction to sudden cardiac death. Recent studies on myocarditis pathogenesis have revealed a triphasic nature of this disease, which influences the diagnostic and therapeutic strategies to adopt in each patient. Endomyocardial biopsy remains the gold standard for diagnosing myocarditis, and several non-invasive diagnostic tools can be used to support the diagnosis. Intravenous immunoglobulin has become part of routine practice in the treatment of myocarditis in paediatric patients at many centres, but its true effect on the cardiac function has been the target of many studies. The aim of this review is to approach the recently discovered facets of paediatric myocarditis regarding its progression to dilated cardiomyopathy.

Experts' recommendations for the management of cardiogenic shock in children

Cardiogenic shock which corresponds to an acute state of circulatory failure due to impairment of myocardial contractility is a very rare disease in children, even more than in adults. To date, no international recommendations regarding its management in critically ill children are available. An experts’ recommendations in adult population have recently been made (Levy et al. Ann Intensive Care 5(1):52, 2015; Levy et al. Ann Intensive Care 5(1):26, 2015). We present herein recommendations for the management of cardiogenic shock in children, developed with the grading of recommendations’ assessment, development, and evaluation system by an expert group of the Groupe Francophone de Réanimation et Urgences Pédiatriques (French Group for Pediatric Intensive Care and Emergencies). The recommendations cover four major fields of application such as: recognition of early signs of shock and the patient pathway, management principles and therapeutic goals, monitoring hemodynamic and biological variables, and circulatory support (indications, techniques, organization, and transfer criteria). Major principle care for children with cardiogenic shock is primarily based on clinical and echocardiographic assessment. There are few drugs reported as effective in childhood in the medical literature. The use of circulatory support should be facilitated in terms of organization and reflected in the centers that support these children. Children with cardiogenic shock are vulnerable and should be followed regularly by intensivist cardiologists and pediatricians. The experts emphasize the multidisciplinary nature of management of children with cardiogenic shock and the importance of effective communication between emergency medical assistance teams (SAMU), mobile pediatric emergency units (SMUR), pediatric emergency departments, pediatric cardiology and cardiac surgery departments, and pediatric intensive care units.

Cyclosporine A Treatment Inhibits Abcc6-Dependent Cardiac Necrosis and Calcification following Coxsackievirus B3 Infection in Mice

Coxsackievirus type B3 (CVB3) is a cardiotropic enterovirus. Infection causes cardiomyocyte necrosis and myocardial inflammation. The damaged tissue that results is replaced with fibrotic or calcified tissue, which can lead to permanently altered cardiac function. The extent of pathogenesis among individuals exposed to CVB3 is dictated by a combination of host genetics, viral virulence, and the environment. Here, we aimed to identify genes that modulate cardiopathology following CVB3 infection. 129S1 mice infected with CVB3 developed increased cardiac pathology compared to 129X1 substrain mice despite no difference in viral burden. Linkage analysis identified a major locus on chromosome 7 (LOD: 8.307, P<0.0001) that controlled the severity of cardiac calcification and necrosis following infection. Sub-phenotyping and genetic complementation assays identified Abcc6 as the underlying gene. Microarray expression profiling identified genotype-dependent regulation of genes associated with mitochondria. Electron microscopy examination showed elevated deposition of hydroxyapatite-like material in the mitochondrial matrices of infected Abcc6 knockout (Abcc6-/-) mice but not in wildtype littermates. Cyclosporine A (CsA) inhibits mitochondrial permeability transition pore opening by inhibiting cyclophilin D (CypD). Treatment of Abcc6 -/- mice with CsA reduced cardiac necrosis and calcification by more than half. Furthermore, CsA had no effect on the CVB3-induced phenotype of doubly deficient CypD-/-Abcc6-/- mice. Altogether, our work demonstrates that mutations in Abcc6 render mice more susceptible to cardiac calcification following CVB3 infection. Moreover, we implicate CypD in the control of cardiac necrosis and calcification in Abcc6-deficient mice, whereby CypD inhibition is required for cardioprotection.

Systematic drug repositioning for a wide range of diseases with integrative analyses of phenotypic and molecular data

Drug repositioning, or the application of known drugs to new indications, is a challenging issue in pharmaceutical science. In this study, we developed a new computational method to predict unknown drug indications for systematic drug repositioning in a framework of supervised network inference. We defined a descriptor for each drug-disease pair based on the phenotypic features of drugs (e.g., medicinal effects and side effects) and various molecular features of diseases (e.g., disease-causing genes, diagnostic markers, disease-related pathways, and environmental factors) and constructed a statistical model to predict new drug-disease associations for a wide range of diseases in the International Classification of Diseases. Our results show that the proposed method outperforms previous methods in terms of accuracy and applicability, and its performance does not depend on drug chemical structure similarity. Finally, we performed a comprehensive prediction of a drug-disease association network consisting of 2349 drugs and 858 diseases and described biologically meaningful examples of newly predicted drug indications for several types of cancers and nonhereditary diseases.

Usefulness of arrhythmias as predictors of death and resource utilization in children with myocarditis

Myocarditis in children can result in significant morbidity and mortality, yet limited prognostic data exist. The aim of this study was to test the hypothesis that pediatric patients with arrhythmias during hospitalization for acute myocarditis have worse outcomes and increased resource utilization. A retrospective study using the Pediatric Health Information System database was performed to examine the effects of clinically significant arrhythmias on in-hospital mortality, length of stay, and costs per day. Data were obtained for children ≤18 years of age, discharged from January 1, 2004 to March 31, 2013, with a diagnosis of myocarditis. Clinically significant tachyarrhythmia was defined as supraventricular tachycardia, atrial fibrillation or flutter, or ventricular tachycardia or fibrillation in patients receiving antiarrhythmic medications or cardioversion. Clinically significant bradyarrhythmia was defined as second-degree, complete, or other heart block for which a pacemaker was placed. Multivariable analyses were performed. A total of 2,041 subjects with myocarditis were identified. Tachyarrhythmias were reported in 234 (11.5%) and bradyarrhythmias in 22 (1.1%). Overall mortality was 8.7%. In multivariable analyses, after considering the effects of gender, age at admission, geographic region, year and month of admission, presence of congenital heart disease or an identified virus, and use of steroids, nonsteroidal anti-inflammatories, or inotropes, and after controlling for clustering by institution, tachyarrhythmias were associated with a 2.3 times increase in the odds of mortality (95% confidence interval 1.6 to 3.3, p < 0.001), a 58% increase in length of stay (95% confidence interval 38% to 82%, p < 0.001), and a 28% increase in costs per day (95% confidence interval 15% to 43%, p < 0.001). Bradyarrhythmia was not associated with mortality, length of stay, or costs per day. In conclusion, tachyarrhythmias are associated with significant increases in mortality and resource utilization in children with myocarditis.

Corticosteroids for viral myocarditis

BACKGROUND

Myocarditis is defined as inflammation of the myocardium accompanied by myocellular necrosis. Experimental evidence suggests that autoimmune mechanisms follow viral infection, resulting in inflammation and necrosis in the myocardium. However, the use of corticosteroids as immunosuppressives for this condition remains controversial.

OBJECTIVES

The existing review was updated. The primary objective of this review is to assess the beneficial and harmful effects of treating acute or chronic viral myocarditis with corticosteroids. The secondary objective is to determine the best dose regimen.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 7 of 12, 2012) on The Cochrane Library, MEDLINE OVID (1946 to July Week 2, 2012), EMBASE OVID (1980 to Week 29, 2012), BIOSIS Previews (1969 to 20 July 2012), ISI Web of Science (1970 to 20th July, 2012), and LILACS (from its inception to 25 July, 2012) , Chinese Biomed Database, CNKI and WANFANG Databases (from their inception to 31 December 2012). We applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of corticosteroids for viral myocarditis compared with no intervention, placebo, supportive therapy, antiviral agents therapy or conventional therapy, including trials of corticosteroids plus other treatment versus other treatment alone, irrespective of blinding, publication status, or language.

DATA COLLECTION AND ANALYSIS

Two review authors extracted data independently. Results were presented as risk ratios (RRs) and mean differences (MDs), both with 95% confidence intervals (CIs).

MAIN RESULTS

Eight RCTs (with 719 participants) were included in this update. The trials were small in size and methodological quality was poor. Viral detection was performed in 38% of participants, among whom 56% had positive results. Mortality between corticosteroids and control groups was non-significant (RR, 0.93, 95% CI 0.70 to 1.24). At 1 to 3 months follow-up, left ventricular ejection fraction (LVEF) was higher in the corticosteroids group compared to the control group (MD 7.36%, 95% CI 4.94 to 9.79), but there was substantial heterogeneity. Benefits were observed in LVEF in two trials with 200 children given corticosteroids (MD 9.00%, 95% CI 7.48 to 10.52). New York Heart Association (NYHA) class and left ventricular end-stage systole diameter (LVESD) were not affected. Creatine phosphokinase (CPK) (MD -104.00 U/L, 95% CI -115.18 to -92.82), Isoenzyme of creatine phosphate MB (CKMB) (MD 10.35 U/L, 95% CI 8.92 to 11.78), were reduced in the corticosteroids group compared to the control group, although the evidence is limited to small participant numbers. There were insufficient data on adverse events.

AUTHORS' CONCLUSIONS

For people diagnosed with viral myocarditis and low LVEF, corticosteroids do not reduce mortality. They may improve cardiac function but the trials were of low quality and small size so this finding must be regarded as uncertain. High-quality, large-scale RCTs should be careful designed to determine the role of corticosteroid treatment for viral myocarditis. Adverse events should also be carefully evaluated.

Myocarditis in a pediatric case of pandemic 2009H1N1 influenza

We report a 6-year-old boy with no major disease history or allergic conditions initially presented with pneumonia, progressed to acute respiratory distress syndrome and acute myocarditis caused by pandemic 2009H1N1 influenza diagnosed with RT-PCR testing, successfully managed with mechanical ventilation and percutaneous cardiopulmonary support system. Marked transient elevation of IgE in acute phase of the disease and the subsequent diagnosis of atopic asthma in our patient suggested a possible role of an underlying allergic condition in the clinicopathological process. Critically ill 2009H1N1-infected patient with acute respiratory failure should carefully be physiologically monitored together with serial assessment of biomarkers aiming at a favorable cardiac outcome by giving the timely diagnosis and intervention.

Demographics, trends, and outcomes in pediatric acute myocarditis in the United States, 2006 to 2011

BACKGROUND

There is a lack of clear diagnostic and management guidelines for acute myocarditis in the pediatric population. We used a multi-institutional database to characterize demographics, practice variability, and outcomes in this population.

METHODS AND RESULTS

Patients with acute myocarditis (n=514) were identified from April 2006 to March 2011 using the Pediatric Health Information System database, and regional variations in management and outcomes were analyzed. Ninety-seven patients (18.9%) received extracorporeal membrane oxygenation, 22 (4.3%) received ventricular assist device, 21 (4.1%) received heart transplantation, and 37 (7.2%) died. Of the 104 patients who received extracorporeal membrane oxygenation or ventricular assist device, 17 (16.3%) had heart transplantation, 25 (24%) died, and 62 (59.6%) showed recovery of myocardial function. There was a decrease in the use of endomyocardial biopsy (P=0.03) and an increase in the use of magnetic resonance imaging (P<0.01) over the study period. Although the use of medications and procedures varied between different regions, the occurrence of death or heart transplantation showed no significant regional associations. The use of extracorporeal membrane oxygenation (odds ratio, 5.8; 95% confidence interval, 2.9-11.4; P<0.01), ventricular assist device (odds ratio, 8.2; 95% confidence interval, 2.7-24.9; P<0.01), and vasoactive medications (odds ratio, 5.7; 95% confidence interval, 1.2-26.1; P=0.03) was independently associated with death/transplantation.

CONCLUSIONS

There is significant temporal and regional variation in the diagnostic modalities and management used for pediatric myocarditis, which continues to have high morbidity and mortality. Extracorporeal membrane oxygenation, ventricular assist device, and vasoactive medications are independently associated with increased mortality/transplantation.

Autoimmune giant cell myocarditis: clinical characteristics, experimental models and future treatments

INTRODUCTION

Although prognosis in acute myocarditis is generally moderate, giant cell myocarditis shows poor prognosis. Giant cell myocarditis is considered to be an autoimmune disease, however, its pathophysiology and specific treatment is yet to be elucidated.

AREAS COVERED

This article reviews the clinical characteristics of autoimmune myocarditis and its possible future treatments. An animal model of experimental autoimmune myocarditis (EAM) is characterized by severe myocardial damage and multinucleated giant cell infiltration, and this has been used as a disease model for human acute giant cell myocarditis. Using experimental models, we reported that NF-κB, cytokines, adhesion molecules and other factors play a critical role in the development of autoimmune myocarditis.

EXPERT OPINION

Giant cell myocarditis, an autoimmune form of myocarditis, has a high mortality rate unless mechanical support or cardiac transplantation is performed. Therefore, further therapeutic applications of novel methodologies are needed to expand the number of alternative choices for treating autoimmune myocarditis.

ST-segment elevation in non-atherosclerotic coronaries: a brief overview

The most common, clinically significant cause of ST elevation is an angiographically demonstrable occlusive disease due to atherosclerotic changes in coronary artery. Often, a patient presenting with non-specific complaints and ST-segment elevation on the electrocardiogram, is sent for a cardiac catheterization only to see no luminal stenosis on the angiogram. This clinical review is intended to inform emergency medicine physicians and internists about the conditions in which ST-segment elevation is accompanied with no atherosclerotic lesion on coronary angiography. These situations make a diverse array of conditions ranging from anomalous coronaries to anatomically normal coronaries with varied degrees of myocardial injury. These conditions are briefly reviewed in this article.