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

Hemodynamic management of cardiogenic shock in the intensive care unit

Hemodynamic derangements are defining features of cardiogenic shock. Randomized clinical trials have examined the efficacy of various therapeutic interventions, from percutaneous coronary intervention to inotropes and mechanical circulatory support (MCS). However, hemodynamic management in cardiogenic shock has not been well-studied. This State-of-the-Art review will provide a framework for hemodynamic management in cardiogenic shock, including a description of the 4 therapeutic phases from initial 'Rescue' to 'Optimization', 'Stabilization' and 'de-Escalation or Exit therapy' (R-O-S-E), phenotyping and phenotype-guided tailoring of pharmacological and MCS support, to achieve hemodynamic and therapeutic goals. Finally, the premises that form the basis for clinical management and the hypotheses for randomized controlled trials will be discussed, with a view to the future direction of cardiogenic shock.

Diagnostic accuracy, clinical characteristics, and prognostic differences of patients with acute myocarditis according to inclusion criteria

INTRODUCTION

The diagnosis of acute myocarditis (AM) is complex due to its heterogeneity and typically is defined by either Electronic Healthcare Records (EHRs) or advanced imaging and endomyocardial biopsy, but there is no consensus. We aimed to investigate the diagnostic accuracy of these approaches for AM.

METHODS

Data on ICD 10th Revision(ICD-10) codes corresponding to AM were collected from two hospitals and compared to cardiac magnetic resonance (CMR)-confirmed or clinically suspected (CS)-AM cases with respect to diagnostic accuracy, clinical characteristics, and all-cause mortality. Next, we performed a review of published AM studies according to inclusion criteria.

RESULTS

We identified 291 unique admissions with ICD-10 codes corresponding to AM in the first three diagnostic positions. The positive predictive value of ICD-10 codes for CMR-confirmed or CS-AM was 36%, and patients with CMR-confirmed or CS-AM had a lower all-cause mortality than those with a refuted diagnosis (P = 0.019). Using an unstructured approach, patients with CMR-confirmed and CS-AM had similar demographics, comorbidity profiles and survival over a median follow-up of 52 months (P = 0.72). Our review of the literature confirmed our findings. Outcomes for patients included in studies using CMR-confirmed criteria were favourable compared to studies with endomyocardial biopsy-confirmed AM cases.

CONCLUSION

ICD-10 codes have poor accuracy in identification of AM cases and should be used with caution in clinical research. There are important differences in management and outcomes of patients according to the selection criteria used to diagnose AM. Potential selection biases must be considered when interpreting AM cohorts and requires standardization of inclusion criteria for AM studies.

Chinese Society of Cardiology guidelines on the diagnosis and treatment of adult fulminant myocarditis

Fulminant myocarditis is an acute diffuse inflammatory disease of myocardium. It is characterized by acute onset, rapid progress and high risk of death. Its pathogenesis involves excessive immune activation of the innate immune system and formation of inflammatory storm. According to China's practical experience, the adoption of the "life support-based comprehensive treatment regimen" (with mechanical circulation support and immunomodulation therapy as the core) can significantly improve the survival rate and long-term prognosis. Special emphasis is placed on very early identification,very early diagnosis,very early prediction and very early treatment.

Contemporary Outcomes of Children With Acute Fulminant Myocarditis Supported With Peripheral Extracorporeal Membrane Oxygenation

Despite extracorporeal membrane oxygenation (ECMO) utilization in nearly 20% of cases, there are limited data in children with acute fulminant myocarditis (AFM) requiring ECMO. Herein we identify risk factors for death or heart transplant (HT) in children with AFM supported with ECMO, describe our experience with left atrial (LA) decompression, and depict long-term outcomes of survivors. We performed a retrospective cohort of patients <18 years with AFM (≤14 days of symptoms, rapid cardiogenic shock, and normal left ventricular [LV] size on presentation) supported with ECMO admitted to a single intensive care unit from 1997 to 2021. Among 28 patients (median age 9 years), 21 (75%) survived to discharge without HT. Patients were supported on ECMO for a median of 6 days. Three patients were bridged to HT with durable ventricular assist devices (VAD). Four patients died, two of whom were supported with VAD. At presentation, seven (25%) patients had high grade or complete atrioventricular block and eight (29%) had ventricular tachycardia. Before ECMO cannulation, 21 (75%) patients received CPR. The death/HT group had higher peak troponin levels (12.5 vs . 1.0 ng/ml, p = 0.02) and initial mean LA or pulmonary capillary wedge pressure (27 vs . 18 mm Hg, p = 0.03). Left atrial decompression was performed in 22 patients (79%). Twenty-two (79%) had acute myocarditis on endomyocardial biopsy. Among transplant-free survivors, 18 (86%) had normalization in LV function (median 7 days); the remaining three patients had persistent mild LV dysfunction at last follow-up (median 842 days). Transplant-free survival of pediatric patients with AFM supported on ECMO was 75% and associated with lower initial LA pressure and lower peak troponin. Recovery in ventricular function among survivors was rapid and durable.

Impella device in fulminant myocarditis: Japanese Registry for Percutaneous Ventricular Assist Device (J-PVAD) registry analysis on outcomes and adverse events

AIMS

Given that fulminant myocarditis, characterized by unstable haemodynamics, is a significant clinical challenge and that traditional pharmacological treatments have limitations, evaluating alternatives such as the Impella device is a crucial focus of this study. Further, this study presents pioneering large-scale registry data on its use in managing fulminant myocarditis.

METHODS AND RESULTS

Data from the Japanese Registry for Percutaneous Ventricular Assist Devices (J-PVAD) were analysed to assess Impella's role in managing fulminant myocarditis from February 2020 to December 2021. The primary outcome was 30-day mortality for those treated with Impella. Of the 269 patients treated with Impella, 107 used Impella standalone, and 162 used ECPELLA (Impella combined with extracorporeal membrane oxygenation). The average age was 54 years, with 42.8% females. Overall, 74.3% survived at 30 days. Specifically, the success rate was 68.5% for the ECPELLA group and 83.2% for the Impella standalone group. Cox regression highlighted that lower estimated glomerular filtration rate and pre-Impella systolic blood pressure increased adverse event risk, while Swan-Ganz catheterization use reduced it. Adverse events were noted in 48.7% of patients, such as bleeding (32.0%) and deteriorating renal function (8.6%).

CONCLUSION

Impella's use in fulminant myocarditis demonstrates encouraging short-term outcomes, albeit with significant adverse events. These findings align with previous mechanical circulatory support studies, emphasizing caution regarding haemorrhagic issues. Further studies are essential to enhance patient selection and treatment approaches.

Asymptomatic Salmonella Myocarditis: A Case Report of a Rare Entity

Enteric fever typically displays symptoms like high fever, abdominal pain, constipation, and headaches, primarily affecting the digestive system. While it is commonly seen as a gastrointestinal infection, it can also lead to rare but significant cardiovascular issues. There have been only a few reported cases of enteric fever causing heart manifestations. We present a case of a young male with enteric fever-induced myocarditis, which, due to its rarity, can be challenging to diagnose and is essentially a diagnosis of exclusion. Cardiac MRI (CMR) is crucial for diagnosis, supported by ECG, echocardiograms, and troponin levels. The treatment involves standard approaches for cardiomyopathy, including angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, and diuretics. However, our patient presented as a case of asymptomatic myocarditis and fully recovered with treatment without any long-lasting heart problems. Our study aims to contribute to the limited body of knowledge on heart-related complications of enteric fever, raising awareness among clinicians of such presentations in enteric fever cases.

Clinical Value of Troponin Levels to Cardiac Function and Prognosis in Patients with Fulminant Myocarditis

Troponin (Tn) is a biomarker related to myocardial necrosis and is elevated in patients with myocarditis. This study aimed to investigate the association between cardiac Tn levels and the course of cardiac function, and prognosis in patients with fulminant myocarditis (FM) receiving percutaneous mechanical circulatory support (MCS).We used data from a multicenter retrospective registry, CHANGE PUMP 2, which included 216 patients with FM who required MCS. Among them, 141 patients whose Tn levels were available were analyzed. The patients were divided into low and high Tn groups according to the median values of TnT and TnI.The median age was 54 years, and 59.6% were male. The TnT and TnI on day 1 (at MCS initiation) were 3.8 (1.4-10.0) and 21.4 (8.4-68.8) ng/mL. While the left ventricular ejection fraction (LVEF) was similar on day 1 (25.0% versus 24.5%), the low Tn group showed better LVEF improvement on day 7 than the high Tn group (45.0% versus 25.3%, P < 0.001). LVEF at 1 year after admission was higher in the low Tn group (65.0% versus 59.7%, P = 0.039). The low Tn group had a better 90-day composite endpoint in death, durable left ventricular assist device implantation, and heart transplantation compared to the high Tn group (hazard ratio 0.47, 95% CI 0.23-0.95).Tn levels were associated with short- and long-term cardiac recovery and adverse outcomes in patients with FM receiving MCS due to cardiogenic shock.

Contemporary National Trends of Mechanical Circulatory Support Among Myocarditis Hospitalizations Before the Pandemic: A National In-patient Database (2005-2019) Study

According to the Global Burden of Disease Project, the morbidity and mortality of myocarditis continue to be a significant worldwide burden. On October 1, 2015, hospital administrative data started using the International Classification of Diseases (ICD)-10 codes instead of the ICD-9. To our knowledge, nationwide trends of myocarditis have not been studied after this update. The NIS database from 2005-2019 was analyzed using ICD-9 and 10 codes. Our search yielded 141,369 hospitalizations due to myocarditis, with 40.9% females. There were 6627 (4.68%) patients who required mechanical circulatory support (MCS) using left ventricular assisted devices (LVAD), intra-aortic balloon pump (IABP), or extracorporeal membrane oxygenation (ECMO). The use of LVAD and ECMO increased significantly during the study period (p-trend 0.003 and <0.001, respectively), whereas the use of IABP decreased during the same period (p-trend 0.025). Our study demonstrated an overall increase in the use of MCS overall in myocarditis, with increasing utilization of more advanced MCS in the forms of LVAD and ECMO.

The "Lightbulb" Sign: A Novel Echocardiographic Finding Using Ultrasound Enhancing Agent in Fulminant COVID-19-Related Myocarditis

We report a case of fulminant COVID-19-related myocarditis requiring venoarterial extracorporeal membrane oxygenation where the use of an ultrasound-enhancing agent demonstrated a previously undescribed echocardiographic finding, the "lightbulb" sign. This sign potentially represents a new area for the use of an ultrasound enhancing agent in the echocardiographic diagnosis of myocarditis.

Role for advanced heart failure therapies in the management of influenza B-associated fulminant myocarditis with recovery

A woman presented to the emergency department for syncope after developing influenza-like symptoms. She tested positive for influenza B. The patient rapidly decompensated into cardiogenic shock over 2 days, requiring aggressive pharmacological therapy and temporary mechanical circulatory support. She made a full recovery. This case highlights the importance of early intervention, urgent transplant evaluation and guideline directed medical therapy in the treatment of fulminant myocarditis secondary to influenza B infection.

Update on Myocarditis: From Etiology and Clinical Picture to Modern Diagnostics and Methods of Treatment

Although the frequency of myocarditis in the general population is very difficult to accurately determine due to the large number of asymptomatic cases, the incidence of this disease is increasing significantly due to better defined criteria for diagnosis and the development of modern diagnostic methods. The multitude of different etiological factors, the diversity of the clinical picture, and the variability of the diagnostic findings make this disease often demanding both for the selection of the diagnostic modality and for the proper therapeutic approach. The previously known most common viral etiology of this disease is today overshadowed by new findings based on immune-mediated processes, associated with diseases that in their natural course can lead to myocardial involvement, as well as the iatrogenic cause of myocarditis, which is due to use of immune checkpoint inhibitors in the treatment of cancer patients. Suspecting that a patient with polymorphic and non-specific clinical signs and symptoms, such as changes in ECG and echocardiography readings, has myocarditis is the starting point in the diagnostic algorithm. Cardio magnetic resonance imaging is non-invasive and is the gold standard for diagnosis and clinical follow-up of these patients. Endomyocardial biopsy as an invasive method is the diagnostic choice in life-threatening cases with suspicion of fulminant myocarditis where the diagnosis has not yet established or there is no adequate response to the applied therapeutic regimen. The treatment of myocarditis is increasingly demanding and includes conservative methods of treating heart failure, immunomodulatory and immunospressive therapy, methods of mechanical circulatory support, and heart transplantation. The goal of developing new diagnostic and therapeutic methods is to reduce mortality from this complex disease, which is still high.

Diagnostic Approach for Suspected Acute Myocarditis: Considerations for Standardization and Broadening Clinical Spectrum

Myocarditis is most recognized in patients with moderate to severe, recent-onset heart failure. However, less typical presentations including myocardial infarction with normal coronary arteries and arrhythmias are important manifestations but less commonly recognized to be caused by myocarditis. Most cases of myocarditis can be self-limiting without specific treatment; however, appropriate identification of risk during the diagnostic process of myocarditis and once a diagnosis is established is of primordial importance to identify patients in need for more specific follow-up and management. We propose a flexible, multitiered approach to the diagnostic process, allowing for capturing of the spectrum of myocarditis at an early time-point, individualized use of diagnostic resources through disease severity phenotyping, and providing structured follow-up care once myocarditis is confirmed. Such diagnostic processes allow for identification of specific etiologies with potential therapeutic consequences or allows for the comprehension of disease chronicity by understanding genetic contributions or elements of persistent immune dysregulation and degree of cardiac damage. The article highlights the evolving field of immunophenotyping in myocarditis, generating a potential for the development of targeted therapeutic approaches. Currently long-term follow-up should be titrated to the refined risk assessments of patients with a diagnosis of myocarditis and includes arrhythmia monitoring and imaging when the results will likely impact management. Genetic testing should be considered in selected cases, and histologic diagnosis may be considered in nonresponders even at later stages.

Immunopathogenesis and immunomodulatory therapy for myocarditis

Myocarditis is an inflammatory cardiac disease characterized by the destruction of myocardial cells, infiltration of interstitial inflammatory cells, and fibrosis, and is becoming a major public health concern. The aetiology of myocarditis continues to broaden as new pathogens and drugs emerge. The relationship between immune checkpoint inhibitors, severe acute respiratory syndrome coronavirus 2, vaccines against coronavirus disease-2019, and myocarditis has attracted increased attention. Immunopathological processes play an important role in the different phases of myocarditis, affecting disease occurrence, development, and prognosis. Excessive immune activation can induce severe myocardial injury and lead to fulminant myocarditis, whereas chronic inflammation can lead to cardiac remodelling and inflammatory dilated cardiomyopathy. The use of immunosuppressive treatments, particularly cytotoxic agents, for myocarditis, remains controversial. While reasonable and effective immunomodulatory therapy is the general trend. This review focuses on the current understanding of the aetiology and immunopathogenesis of myocarditis and offers new perspectives on immunomodulatory therapies.

Treatment strategy for acute myocarditis in pediatric patients requiring emergency intervention

BACKGROUND

Patients with acute myocarditis present with a wide range of symptoms. Treatment strategies for pediatric patients with circulatory failure comprise extracorporeal membrane oxygenation (ECMO), emergency temporary pacing, and pharmacotherapy. However, they remain controversial. ECMO is an effective treatment but gives rise to several complications; the goal is therefore to avoid excessive treatment as much as possible. We aimed to evaluate the importance of electrocardiogram findings in differentiating severity and establish an appropriate treatment strategy in pediatric patients with acute myocarditis who required emergency interventions.

METHODS

This retrospective study enrolled pediatric patients admitted to and treated in our hospital for acute myocarditis between April 1983 and December 2021. Patients were retrospectively divided into whether circulatory failure occurred (ECMO or temporary pacing was needed; emergency intervention group) or not (pharmacotherapy alone).

RESULTS

Of the 26 pediatric patients, 11 experienced circulatory failure while 15 did not. In the circulatory failure group, six patients were treated with ECMO (ECMO group) and five patients with temporary pacing (pacing group). In the pacing group, all patients were diagnosed with complete and/or advanced atrioventricular block (CAVB and/or advanced AVB) and narrow QRS. Furthermore, these patients improved only with temporary pacing and pharmacotherapy, without requiring ECMO. Wide QRS complexes (QRS ≥ 0.12 ms) with ST-segment changes were detected on admission in five of six patients in the ECMO group and none in the pacing group (P = 0.015). Although all patients in the ECMO group experienced complications, none did in the pacing group (P < 0.008).

CONCLUSIONS

Regarding emergency intervention for acute myocarditis, ECMO or temporary pacing could be determined based on electrocardiogram findings, particularly wide QRS complexes with ST-segment changes on admission. It is important to promptly introduce ECMO in patients with wide QRS complexes with ST-segment changes, however, patients with CAVB and/or advanced AVB and narrow QRS could improve without undergoing ECMO. Therefore, excessive treatment should be avoided by separating ECMO from temporary pacing based on electrocardiogram findings on admission.

A case of fulminant myocarditis with full recovery after a 38-h sustained asystole

Key Clinical Message

Even if cardiac rhythm deteriorated to asystole in the clinical course of fulminant myocarditis, cardiac function may recover, and the patient may be discharged without brain damage, if circulation could be maintained by appropriate mechanical cardiac supports.

Abstract

A 69-year-old man was diagnosed with fulminant myocarditis with circulatory collapse. His cardiac rhythm deteriorated to asystole on the second day; however, circulatory status was maintained through extracorporeal membrane oxygenation and intra-aortic balloon pumping. After 38 h-lasting asystole, his heart resumed beating. He was discharged without neurological deficits on Day 25.

Advancing Precision Medicine in Myocarditis: Current Status and Future Perspectives in Endomyocardial Biopsy-Based Diagnostics and Therapeutic Approaches

The diagnosis and specific and causal treatment of myocarditis and inflammatory cardiomyopathy remain a major clinical challenge. Despite the rapid development of new imaging techniques, endomyocardial biopsies remain the gold standard for accurate diagnosis of inflammatory myocardial disease. With the introduction and continued development of immunohistochemical inflammation diagnostics in combination with viral nucleic acid testing, myocarditis diagnostics have improved significantly since their introduction. Together with new technologies such as miRNA and gene expression profiling, quantification of specific immune cell markers, and determination of viral activity, diagnostic accuracy and patient prognosis will continue to improve in the future. In this review, we summarize the current knowledge on the pathogenesis and diagnosis of myocarditis and inflammatory cardiomyopathies and highlight future perspectives for more in-depth and specialized biopsy diagnostics and precision, personalized medicine approaches.

Significance of Anteroseptal Late Gadolinium Enhancement Among Patients With Acute Myocarditis

Anteroseptal location of late gadolinium enhancement (LGE) in patients with acute myocarditis (AM) detected by cardiovascular magnetic resonance may indicate an independent marker of unfavorable outcomes according to recent data. We aimed to evaluate the clinical characteristics, management, and inhospital outcomes in patients with AM with positive LGE based on its presence in the anteroseptal location. We analyzed data from 262 consecutive patients hospitalized with a diagnosis of AM with positive LGE within 5 days of hospitalization (n = 425). Patients were divided into 2 groups: those with anteroseptal LGE (n = 25, 9.5%) and those with non-anteroseptal LGE (n = 237, 90.5%). Except for age that was higher in patients with anteroseptal LGE, the demographic and clinical characteristics did not differ significantly between both groups including past medical history, clinical presentation, electrocardiogram parameters, and lab values. Moreover, patients with anteroseptal LGE were more likely to present with reduced left ventricular ejection fraction and to receive congestive heart failure treatments. Although univariate analysis showed that patients with anteroseptal LGE were more likely to have inhospital major adverse cardiac events (28% vs 9%, p = 0.003), there was no difference inhospital outcomes on multivariable analysis between both groups (hazard ratio, 1.17 [95% confidence interval, 0.32 to 4.22], p = 0.81). A higher left ventricular ejection fraction in either echocardiography or cardiovascular magnetic resonance corresponded to better inhospital outcomes regardless of the presence or absence of anteroseptal LGE. In conclusion, the presence of anteroseptal LGE did not confer additional prognostic value for inhospital outcomes.

HHV-6 Myocarditis Progressing to Ventricular Standstill Requiring Cardiac Transplant

Human herpesvirus-6 (HHV-6) is an increasingly recognized cause of myocarditis. We present the case of a 46-year-old woman who presented with fulminant HHV-6 myocarditis requiring heart transplantation. (Level of Difficulty: Advanced.).

Low T3 syndrome is associated with 30-day mortality in adult patients with fulminant myocarditis

Background

Fulminant myocarditis (FM) is a critical disease with high early mortality. Low triiodothyronine syndrome (LT3S) was a strong predictor of poor prognosis of critical diseases. This study investigated whether LT3S was associated with 30-day mortality in FM patients.

Methods

Ninety-six FM patients were divided into LT3S (n=39, 40%) and normal free triiodothyronine (FT3) (n=57, 60%) groups based on serum FT3 level. Univariable and multivariable logistic regression analyses were performed to identify independent predictors of 30-day mortality. Kaplan-Meier curve was used to compare 30-day mortality between two groups. Receiver operating characteristic (ROC) curve and decision curve analysis (DCA) were used to assess the value of FT3 level for 30-day mortality prediction.

Results

Compared to normal FT3 group, LT3S group had higher incidence of ventricular arrhythmias, worse hemodynamics, worse cardiac function, more severe kidney impairment, and higher 30-day mortality (48.7% vs. 12.3%, P<0.001). In univariable analysis, LT3S (odds ratio [OR]:6.786, 95% confidence interval [CI]:2.472-18.629, P<0.001) and serum FT3 (OR:0.272, 95%CI:0.139-0.532, P<0.001) were significant strong predictors of 30-day mortality. After adjustment for confounders in multivariable analysis, LT3S (OR:3.409, 95%CI:1.019-11.413, P=0.047) and serum FT3 (OR:0.408, 95%CI:0.199-0.837, P=0.014) remained independent 30-day mortality predictors. The area under the ROC curve of FT3 level was 0.774 (cut-off: 3.58, sensitivity: 88.46%, specificity: 62.86%). In DCA, FT3 level showed good clinical-application value for 30-day mortality prediction.

Conclusion

In FM patients, LT3S could independently predict 30-day mortality. FT3 level was a strong 30-day mortality predictor and a potentially useful risk-stratification biomarker.

Fulminant Myocarditis: When One Size Does Not Fit All - A Critical Review of the Literature

Fulminant myocarditis, rather than being a distinct form of myocarditis, is instead a peculiar clinical presentation of the disease. The definition of fulminant myocarditis has varied greatly in the last 20 years, leading to conflicting reports on prognosis and treatment strategies, mainly because of varied inclusion criteria in different studies. The main conclusion of this review is that fulminant myocarditis may be due to different histotypes and aetiologies that can be diagnosed only by endomyocardial biopsy and managed by aetiology-directed treatment. This life-threatening presentation requires rapid, targeted management both in the short term (mechanical circulatory support, inotropic and antiarrhythmic treatment and endomyocardial biopsy) and in the long term (including prolonged follow-up). Fulminant presentation has also recently been identified as a risk factor for worsened prognosis, even long after the resolution of the acute phase of myocarditis.

Left ventricular function changes and echocardiographic predictors in adult survivors of fulminant myocarditis treated with the Chinese protocol

Disagreement exists regarding the long-term prognosis and recovery of left ventricular (LV) function in patients with fulminant myocarditis (FM). This study reported the outcome and LV ejection fraction (EF) changes in FM treated with Chinese protocol, and assessed whether global longitudinal strain (GLS) by two-dimensional speckle tracking echocardiography (2-D STE) could provide additional information. This retrospective study included 46 FM adult patients who applied timely circulatory support and immunomodulatory therapy with adequate doses of both glucocorticoids and immunoglobulins as core approaches and survived after acute phase. They all presented with acute onset of cardiac symptoms < 2 weeks. LV end-diastolic dimensions, LVEF and GLS at discharge and 2-year were obtained and compared. We then performed linear regression and ROC analysis to determine independent factors to predict normalization of GLS at 2-year. At 2 years, the survival was 100% in our cohort. And the GLS improved modestly (15.40 ± 3.89% vs 17.24 ± 2.89%, P = 0.002). At two years, a proportion of patients whose LV function remained abnormal, being 22% evaluated by EF (< 55%) and higher to 37% by GLS (< 17%). Moreover, GLS at discharge but not at presentation correlated with GLS at 2-year (r = 0.402, P = 0.007). The FM adult treated with Chinese protocol have good survival and modest improvement of LV function during 2-year.

Optimising the ECMO treatment regimen increases the survival rate for adult patients with acute fulminant myocarditis: A single-centre retrospective cohort study

Background

Applying Extracorporeal membrane oxygenation (ECMO) to patients with acute fulminant myocarditis (AFM) reduces their mortality. The survival rate is 55.6-71.9% for adult AFM patients, which is lower than that for paediatric patients (63-81%). In our centre, the survival rate of ECMO for adult patients with AFM was 66.7% from January 2003 to 2012. In January 2013, the therapeutic regimen was optimised, and then the survival rate increased to 89.1% by January 2022. This article analyses the reasons for the improved survival rate following the optimisation of treatment protocols.

Methods

The data for adult patients with AFM who underwent ECMO for a poor response conventional treatment from January 2003 to January 2022 were reviewed. According to different treatment regimens, the AFM patients were divided into an old and a new regimen group. Univariate and multivariate logistic regression analyses were performed on the data before and after ECMO.

Results

Fifty-five patients were enrolled in the age (31.2 ± 11.3), including 24 males. Forty-nine patients were weaned successfully from ECMO [duration: (4.1 ± 1.8) d], all of whom were discharged from the hospital, with a survival rate of 89.1%. Compared with the old regimen group, the new regimen group had a shorter duration of shock to ECMO, a lower proportion of patients receiving extracorporeal cardiopulmonary resuscitation (ECPR), a lower Vasoactive Inotropic Score (VIS), and lower levels of lactic acid, and high-sensitivity troponin T before ECMO (p &lt; 0.05). Compared with the old regimen group, after ECMO, the new regimen group had lower ECMO flow, lower proportion of left ventricular dilation and lower limb ischemia injury, the duration of ECMO was shorter, and significantly improved the survival rate, the difference was statistically significant (P &lt; 0.05). The duration of shock to ECMO and VIS before ECMO were independent risk factors for the survival rate (p &lt; 0.05).

Conclusion

Early ECMO initiation in adult AFM patients with a poor response to conventional therapy and low-flow ECMO to meet metabolic needs can reduce serious complications affecting the prognosis, may be associated with better outcomes.

Patients with fulminant myocarditis supported with veno-arterial extracorporeal membrane oxygenation: a systematic review and meta-analysis of short-term mortality and impact of risk factors

Fulminant myocarditis (FM) may lead to cardiogenic shock requiring veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Results of effectiveness studies of VA-ECMO have been contradictory. We evaluated the aggregate short-term mortality after VA-ECMO and predictive factors in patients with FM. We systematically searched in electronic databases (February 2022) to identify studies evaluating short-term mortality (defined as mortality at 30 days or in-hospital) after VA-ECMO support for FM. We included studies with 5 or more patients published after 2009. We assessed the quality of the evidence using the QUIPS and GRADE tools. Mortality was pooled using random effect models. We performed meta-regression to explore heterogeneity based on a priori defined factors. We included 54 observational studies encompassing 2388 FM patients supported with VA-ECMO. Median age was 41 years (25th to 75th percentile 37-47), and 50% were female. The pooled short-term mortality was 35% (95% CI 29-40%, I² = 69%; moderate certainty). By meta-regression, studies with younger populations showed lower mortality. Female sex, receiving a biopsy, cardiac arrest, left ventricular unloading, and earlier recruitment time frame, did not explain heterogeneity. These results remained consistent regardless of continent and the risk of bias category. In individual studies, low pH value, high lactate, absence of functional cardiac recovery on ECMO, increased burden of malignant arrhythmia, high peak coronary markers, and IVIG use were identified as independent predictors of mortality. When conventional therapies have failed, especially in younger patients, cardiopulmonary support with VA-ECMO should be considered in the treatment of severe FM.

10-year survival outcome after clinically suspected acute myocarditis in adults: A nationwide study in the pre-COVID-19 era

BACKGROUND

Clinical courses of acute myocarditis are heterogeneous in populations and geographic regions. There is a dearth of long-term outcomes data for acute myocarditis prior to the coronavirus disease pandemic, particularly in the older and female population. This study aimed to provide the nationwide epidemiologic approximates of clinically suspected acute myocarditis across adults of all ages over the long term.

METHODS

From the nationwide governmental health insurance database, a retrospective cohort comprised all patients aged 20-79 who were hospitalized for clinically suspected acute myocarditis without underlying cardiac diseases from 2006 to 2018. The complicated phenotype was defined as requiring hemodynamic or major organ support. Over 10 years, all-cause mortality and index event-driven excess mortality were evaluated according to young-adult (20-39 years), mid-life (40-59 years), and older-adult (60-79 years) age groups.

RESULTS

Among 2,988 patients (51.0±16.9 years, 46.2% women), 362 (12.1%) were of complicated phenotype. Of these, 163 (45.0%) had died within 1 month. All-cause death at 30 days occurred in 40 (4.7%), 52 (4.8%), and 105 (10.0%) patients in the young-adult, mid-life, and older-adult groups, respectively. For 10 years of follow-up, all-cause death occurred in 762 (25.5%). Even in young adult patients with non-complicated phenotypes, excess mortality remained higher compared to the general population.

CONCLUSION

In hospitalized patients with clinically suspected acute myocarditis, short-term mortality is high both in young and older adults, particularly those with comorbidities and severe clinical presentation. Furthermore, excess mortality remains high for at least 10 years after index hospitalization in young adults.

Successful rescue of fulminant myocarditis with mechanical circulatory support and immunosuppression therapy: A case report

Myocarditis is challenging to diagnose because of its various clinical manifestations. Fulminant myocarditis (FM) is a severe type of myocarditis characterized by heart failure, malignant arrhythmia, cardiogenic shock, and cardiac arrest. Its early diagnosis and timely treatment are crucial for a positive long-term prognosis. Here we report a case of 42-year-old woman who presented with fever, chest pain, and cardiogenic shock. An initial examination showed increased myocardial enzyme levels and diffuse ST-segment elevation. Urgent coronary angiography excluded coronary artery stenosis. Echocardiography revealed decreased left ventricular systolic function. Cardiac magnetic resonance imaging revealed cardiomyocyte necrosis and interstitial inflammatory edema. The patient was diagnosed with FM and administered antiviral and anti-infective agents, glucocorticoid, immunoglobulin, and supported with temporary cardiac pacemaker and positive airway therapy, and treated with continuous renal replacement therapy. As her clinical condition deteriorated rapidly, we immediately started an intra-aortic balloon pump and veno-arterial extracorporeal membrane oxygenation. She was discharged on day 15 and recovered normally during follow-up. The early initiation of mechanical circulatory support and immunosuppression are life-saving tools for the treatment of FM.

Waitlist and post-transplant outcomes for children with myocarditis listed for heart transplantation over 3 decades

BACKGROUND

There is limited and conflicting information on waitlist and transplant outcomes for children with myocarditis.

METHODS

Retrospective review included children with myocarditis and dilated cardiomyopathy (DCM) listed for HT from January 01, 1993 to December 31, 2019 in the Pediatric Heart Transplant Society database. Clinical characteristics, waitlist and post-HT outcomes (graft loss, rejection, cardiac allograft vasculopathy, infection and malignancy) for children listed from early (1993-2008) and current era (2009-2019) with myocarditis were evaluated and compared to those with DCM.

RESULTS

Of 9755 children listed, 322 (3.3%) had myocarditis and 3178 (32.6%) DCM. Compared to DCM, children with myocarditis in the early and the current era were significantly more likely to be listed at higher urgency; be in intensive care unit; on mechanical ventilation; extracorporeal membrane oxygenation and ventricular assist device (p < 0.05 for all). While unadjusted analysis revealed lower transplant rates and higher waitlist mortality for children with myocarditis, in multivariable analysis, myocarditis was not a risk factor for waitlist mortality. Myocarditis, however, was a significant risk factor for early phase post-HT graft loss (HR 2.46; p = 0.003). Waitlist and post-HT survival for children with myocarditis were similar for those listed and transplanted in the early era to those listed and transplanted in the current era (p > 0.05 for both).

CONCLUSIONS

Children with myocarditis have a higher acuity of illness at listing and at HT and have inferior post-HT survival compared to children with DCM. Outcomes for children with myocarditis have not improved over the 3 decades and efforts are needed to improve outcomes for this cohort.

The Role of MicroRNAs in Myocarditis-What Can We Learn from Clinical Trials?

Myocarditis is an inflammatory disease of the heart with a viral infection as the most common cause. It affects most commonly young adults. Although endomyocardial biopsy and cardiac magnetic resonance are used in the diagnosis, neither of them demonstrates all the required qualities. There is a clear need for a non-invasive, generally available diagnostic tool that will still remain highly specific and sensitive. These requirements could be possibly met by microribonucleic acids (miRNAs), which are small, non-coding RNA molecules that regulate many fundamental cell functions. They can be isolated from cells, tissues, or body fluids. Recently, several clinical studies have shown the deregulation of different miRNAs in myocarditis. The phase of the disease has also been evidenced to influence miRNA levels. These changes have been observed both in adult and pediatric patients. Some studies have revealed a correlation between the change in particular miRNA concentration and the degree of cardiac damage and inflammation. All of this indicates miRNAs as potential novel biomarkers in the diagnosis of myocarditis, as well as a prognostic tool for this condition. This review aims to summarize the current knowledge about the role of miRNAs in myocarditis based on the results of clinical studies.

Different Phases of Disease in Lymphocytic Myocarditis: Clinical and Electrophysiological Characteristics

BACKGROUND

Endomyocardial biopsy (EMB) is required to make a definite diagnosis of lymphocytic myocarditis (LM), to identify its etiology, and to classify LM into different phases.

OBJECTIVES

This study aims to characterize and compare clinical and electrophysiological characteristics of different biopsy-proven LM phases, namely acute myocarditis (AM), chronic active myocarditis (CAM), and healed myocarditis (HM).

METHODS

All patients with a diagnosis of LM at 3 Italian referral centers were prospectively enrolled. According to EMB findings, LM was classified as AM, CAM, or HM; per-group comparisons of clinical presentations, noninvasive, and invasive findings are reported.

RESULTS

Among the 122 enrolled patients (AM, n = 44; CAM, n = 42; HM, n = 36), complex ventricular arrhythmias were very common overall (n = 109, 89%), but ventricular fibrillation was slightly more prevalent in AM (P = 0.028). Cardiac magnetic resonance imaging showed late gadolinium enhancement in more patients with HM and CAM than AM (94.4% vs 92.9% vs 50%; P < 0.001), whereas edema was more common in AM than in CAM, being absent in HM (90.9% vs 50% vs 0%; P < 0.001). Accordingly, edema was the strongest independent clinical predictor of EMB-proven active inflammation. Electroanatomical mapping revealed a lower prevalence of low-voltage areas in AM than in CAM or HM. We observed a strong association between edema at a specific myocardial segment and normal voltages at that site (odds ratio: 0.24; 95% CI: 0.10-0.54; P < 0.01), as well as between late gadolinium enhancement and low-voltage areas (odds ratio: 2.86; 95% CI: 1.19-6.97; P = 0.019).

CONCLUSIONS

LM is a highly heterogeneous disease, and its different phases are characterized by diverse clinical, morphological, and electrophysiological features. Further research is required to identify electroanatomical markers of inflammation.

Cardiac Muscle Training-A New Way of Recognizing and Supporting Recovery for LVAD Patients in the Pediatric Population

Patients with refractory heart failure due to chronic progressive cardiac myopathy (CM) may require mechanical circulatory support as a bridge to transplantation. A few patients can be weaned from support devices if recovery can be achieved. The identification of these patients is of great importance as recovery may be missed if the heart is unloaded by the ventricular assist device (VAD). Testing the load-bearing capacity of the supported left ventricle (LV) by temporarily and gradually reducing mechanical support during cardiac exercise can help identify responders and potentially aid the recovery process. An exercise training protocol was used in 3 patients (8 months, 18 months and 8 years old) with histological CM findings and myocarditis. They were monitored regularly using clinical information and functional imaging with VAD support. Echocardiographic examination included both conventional real-time 3D echocardiography (RT3DE) and speckle tracking (ST). A daily temporary reduction in pump rate (phase A) was followed by a permanent reduction in rate (phase B). Finally, pump stops of up to 30 min were performed once a week (phase C). The final decision on explantation was based on at least three pump stops. Two patients were weaned and successfully removed from the VAD. One of them was diagnosed with acute viral myocarditis. The other had chronic myocarditis with dilated myopathy and mild interstitial fibrosis. The noninvasive assessment of cardiac output and strain under different loading conditions during VAD therapy is feasible and helps identify candidates for weaning despite severe histological findings. The presented protocol, which incorporates new echocardiographic techniques for determining volume and deformation, can be of great help in positively guiding the process of individual recovery, which may be essential for selecting and increasing the number of patients to be weaned from VAD.

Prognostic relevance of demographic factors in cardiac magnetic resonance-proven acute myocarditis: A cohort study

Aim

Acute myocarditis (AM) is a heterogeneous condition with variable estimates of survival. Contemporary criteria for the diagnosis of clinically suspected AM enable non-invasive assessment, resulting in greater sensitivity and more representative cohorts. We aimed to describe the demographic characteristics and long-term outcomes of patients with AM diagnosed using non-invasive criteria.

Methods and results

A total of 199 patients with cardiac magnetic resonance (CMR)-confirmed AM were included. The majority (n = 130, 65%) were male, and the average age was 39 ± 16 years. Half of the patients were White (n = 99, 52%), with the remainder from Black and Minority Ethnic (BAME) groups. The most common clinical presentation was chest pain (n = 156, 78%), with smaller numbers presenting with breathlessness (n = 25, 13%) and arrhythmias (n = 18, 9%). Patients admitted with breathlessness were sicker and more often required inotropes, steroids, and renal replacement therapy (p < 0.001, p < 0.001, and p = 0.01, respectively). Over a median follow-up of 53 (IQR 34-76) months, 11 patients (6%) experienced an adverse outcome, defined as a composite of all-cause mortality, resuscitated cardiac arrest, and appropriate implantable cardioverter defibrillator (ICD) therapy. Patients in the arrhythmia group had a worse prognosis, with a nearly sevenfold risk of adverse events [hazard ratio (HR) 6.97; 95% confidence interval (CI) 1.87-26.00, p = 0.004]. Sex and ethnicity were not significantly associated with the outcome.

Conclusion

AM is highly heterogeneous with an overall favourable prognosis. Three-quarters of patients with AM present with chest pain, which is associated with a benign prognosis. AM presenting with life-threatening arrhythmias is associated with a higher risk of adverse events.

Research focus and theme trend on fulminant myocarditis: A bibliometric analysis

Aims

This study intends to explore the research focus and trends of fulminant myocarditis (FM) to have a better understanding of the topic.

Materials and methods

The data were downloaded from the Web of Science (WoS) database using the topic (TS) advanced search strategy. Many instruments were used to extract, analyze, and visualize the data, such as Microsoft Excel, HistCite Pro, GunnMap, BibExcel, and VOSviewer.

Results

From 1985 to 2022, 726 documents were indexed in the WoS. The United States and Columbia University were the most productive country and institutions. Keywords co-occurrence was carried out and four research themes were identified. In addition, the top three prolific authors, the first three highly cited authors, and the core authors of the author co-citation network were identified. The topics that they kept an eye on were analyzed, and the research areas of key authors were similar to the results of keyword co-occurrence. The hot topics of FM were related to the mechanical circulatory support, etiology, diagnosis, and the disease or therapy associated with FM.

Conclusion

This study carried out a systematic analysis of the documents related to FM from 1985 to 2022, which can provide a guideline for researchers to understand the theme trend to promote future research to be carried out.

Fulminant Influenza a Myocarditis Complicated by Transient Ventricular Wall Thickening and Cardiac Tamponade

Myocarditis is an infrequent complication of influenza infection that is most often diagnosed clinically in the setting of confirmed influenza infection and elevated cardiac enzymes. Pericarditis can also occur in cases of influenza myocarditis and may require pericardiocentesis for tamponade. Patients with fulminant myocarditis have cardiogenic shock; however, echocardiographic findings may be subtle, showing a preserved ejection fraction and diffuse left ventricular wall thickening (compared to baseline) due to inflammatory edema. Recognizing these echocardiographic findings in the appropriate clinical setting facilitates the early recognition of fulminant myocarditis. Therefore, we report a case of fulminant influenza A myocarditis in healthy 37-year-old women complicated by transient left ventricular wall thickening and tamponade, highlighting the importance of early diagnosis and supportive management for a successful outcome.

Acute Lymphocyte Myocarditis Associated with Influenza Vaccination

An elderly patient was admitted to our hospital for acute heart failure soon after receiving influenza vaccination. On admission, chest radiography revealed pulmonary edema. An electrocardiogram showed poor R progression, and echocardiography showed diffuse hypokinesis and myocardial edema. The serum troponin level was elevated. A histopathological evaluation indicated active myocarditis with lymphocyte-predominant infiltrates. A drug-induced lymphocyte stimulation test (DLST) was positive. The patient rapidly recovered from heart failure after treatment with conventional heart failure drugs, such as intravenous diuretics and vasodilators. These experimental data and the clinical course suggest that influenza vaccination was responsible for heart failure due to acute lymphocyte myocarditis.

Influenza Myopericarditis and Pericarditis: A Literature Review

Myopericarditis is a rare complication of influenza infection. The presentation may range from mild and frequently unrecognized, to fulminant and potentially complicated by cardiogenic and/or obstructive shock (tamponade), which is associated with high mortality. We performed a review of literature on all influenza pericarditis and myopericarditis cases according to PRISMA guidelines using the PubMed search engine of the Medline database. Seventy-five cases of influenza myopericarditis and isolated pericarditis were identified from 1951 to 2021. Influenza A was reported twice as often as influenza B; however, influenza type did not correlate with outcome. Men and elderly patients were more likely to have isolated pericarditis, while women and younger patients were more likely to have myopericarditis. All included patients had pericardial effusion, while 36% had tamponade. Tamponade was more common in those with isolated pericarditis (41.2%) than myopericarditis (13.8%). Cardiogenic shock was more common in patients with myopericarditis (64%), with an overall mortality rate of 14.7%. Nearly 88% of the recovered patients remained without long-term complications reported. Conclusion: Influenza A appears a more common cause of pericarditis and myopericarditis. Isolated pericarditis was more commonly associated with tamponade but without reported deaths, whereas myopericarditis was more commonly associated with cardiogenic shock and death (19%).

Long-term cardiac surveillance and outcomes of COVID-19 patients

Acute cardiac manifestions of COVID-19 have been well described, while chronic cardiac sequelae remain less clear. Various studies have shown conflicting data on the prevalence of new or worsening cardiovascular disease, myocarditis or cardiac dysrhythmias among patients recovered from COVID-19. Data are emerging that show that patients recovering from COVID-19 have an increased incidence of myocarditis and arrhythmias after recovery from COVID-19 compared with the control groups without COVID-19. The incidence of myocarditis after COVID-19 infection is low but is still significantly greater than the incidence of myocarditis from a COVID-19 vaccine. There have been several studies of athletes who underwent a variety of screening protocols prior to being cleared to return to exercise and competition. The data show possible, probable or definite myocarditis or cardiac injury among 0.4–3.0% of the athletes studied. Recent consensus statements suggest that athletes with full recovery and absence of cardiopulmonary symptoms may return to exercise and competition without cardiovascular testing. In conclusion, patients with COVID-19 may be expected to have an increased risk of cardiovascular disease, myocarditis or arrhythmias during the convalescent phase. Fortunately, the majority of patients, including athletes may return to their normal activity after recovery from COVID 19, in the absence of persisting cardiovascular symptoms.

Specialized Proresolving Mediators Protect Against Experimental Autoimmune Myocarditis by Modulating Ca2+ Handling and NRF2 Activation

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Administration of BML-111, a stable LXA4 analog, protects against cardiac dysfunction by avoiding Ca²⁺ mishandling induced by autoimmune myocarditis in a mouse model.

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Beneficial effects of the SPMs on intracellular Ca²⁺ handling are mainly caused by a regulation of SERCA2A by NRF2.

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Cardiac tissue obtained from individuals diagnosed with myocarditis, compared with healthy myocardium tissues, displayed depressed mRNA levels of ATP2A2 (SERCA2A) and NF2L2 (NRF2).

Specialized proresolving mediators and, in particular, 5(S), (6)R, 7-trihydroxyheptanoic acid methyl ester (BML-111) emerge as new therapeutic tools to prevent cardiac dysfunction and deleterious cardiac damage associated with myocarditis progression. The cardioprotective role of BML-111 is mainly caused by the prevention of increased oxidative stress and nuclear factor erythroid-derived 2-like 2 (NRF2) down-regulation induced by myocarditis. At the molecular level, BML-111 activates NRF2 signaling, which prevents sarcoplasmic reticulum–adenosine triphosphatase 2A down-regulation and Ca²⁺ mishandling, and attenuates the cardiac dysfunction and tissue damage induced by myocarditis.

Neurological Manifestations of Myocarditis

PURPOSE OF REVIEW

The present review discusses the neurological complications associated with myocarditis of different etiologies.

RECENT FINDINGS

Myocarditis can be idiopathic or caused by different conditions, including toxins, infections, or inflammatory diseases. Clinical findings are variable and range from mild self-limited shortness of breath or chest pain to hemodynamic instability which may result in cardiogenic shock and death. Several neurologic manifestations can be seen in association with myocarditis. Tissue remodeling, fibrosis, and myocyte dysfunction can result in heart failure and arrhythmias leading to intracardiac thrombus formation and cardioembolism. In addition, peripheral neuropathies, status epilepticus, or myasthenia gravis have been reported in association with specific types of myocarditis. Multiple studies suggest the increasing risk of neurologic complications in patients with myocarditis. Neurologists should maintain a high suspicion of myocarditis in cases presenting with both cardiovascular and neurological dysfunction without a clear etiology.

Mechanisms and Therapeutic Strategies of Viral Myocarditis Targeting Autophagy

Viral myocarditis is caused by infection with viruses or bacteria, including coxsackievirus B3 (CVB3), and is characterized by acute or chronic inflammatory responses in the heart. The mortality associated with severe viral myocarditis is considerable. In some patients, viral myocarditis may develop into dilated cardiomyopathy or heart failure. Autophagy is involved in a wide range of physiological processes, including viral infection and replication. In the present review, we focus on the responses of cardiac tissues, cardiomyocytes, and cardiac fibroblasts to CVB3 infection. Subsequently, the effects of altered autophagy on the development of viral myocarditis are discussed. Finally, this review also examined and assessed the use of several popular autophagy modulating drugs, such as metformin, resveratrol, rapamycin, wortmannin, and 3-methyladenine, as alternative treatment strategies for viral myocarditis.

Diagnosing COVID-19 myocarditis in athletes using cMRI

An early report during the SARS-CoV-2 (COVID-19) outbreak noted myocardial involvement with cardiac troponin I (cTnI) levels >99^th percentile in approximately 20% of hospitalized patients. Patients with cTnI elevations had higher in-hospital mortality. Additionally, myocarditis is associated with exercise-related sudden cardiac death in athletes. Therefore, reports of COVID-19 myocarditis concerned the sports cardiology community, which issued two guidelines on managing athletes with COVID-19 infection. We reviewed reports of myocardial involvement in athletes after COVID-19 infection published before June 2021. The incidence of the diagnosis of myocarditis in athletes post-COVID-19 ranged from 0 to 15.4% based on cardiac magnetic resonance imaging (cMRI) performed 10 to 194 days after initial diagnosis of COVID-19. Only a few studies adhered to accepted myocarditis diagnostic guidelines and only two studies included a control group of uninfected athletes. There was significant heterogeneity in the method and protocols used in evaluating athletes post-COVID-19. The incidence of COVID-19 myocarditis in athletes appears to be over-diagnosed. The evaluation of myocarditis post-COVID-19 should be individually performed and managed according to the current guidelines. This can potentially prevent needless training restrictions and the inability to participate in competitive sports.

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.

COVID-lateral damage: cardiovascular manifestations of SARS-CoV-2 infection

Early in the pandemic, concern that cardiovascular effects would accompany COVID-19 was fueled by lessons from the first SARS epidemic, knowledge that the SARS-COV2 entry receptor (Angiotensin-converting enzyme 2, ACE2) is highly expressed in the heart, early reports of myocarditis, and first-hand accounts by physicians caring for those with severe COVID-19. Over 18 months, our understanding of the cardiovascular manifestations has expanded greatly, leaving more new questions than those conclusively answered. Cardiac involvement is common (∼20%) but not uniformly observed in those who require treatment in a hospitalized setting. Cardiac MRI studies raise the possibility of manifestations in those with minimal symptoms. Some appear to experience protracted cardiovascular symptoms as part of a larger syndrome of post-acute sequelae of COVID-19. Instances of vaccine induced thrombosis and myocarditis are exceedingly rare but illustrate the need to monitor the cardiovascular safety of interventions that induce inflammation. Here, we will summarize the current understanding of potential cardiovascular manifestations of SARS-COV2. To provide proper context, paradigms of cardiovascular injury due to other inflammatory processes will also be discussed. Ongoing research and a deeper understanding COVID-19 may ultimately reveal new insight into the mechanistic underpinnings of cardiovascular disease. Thus, in this time of unprecedented suffering and risk to global health, there exists the opportunity that well conducted translational research of SARS-COV2 may provide health dividends that outlast the current pandemic.

Fulminant myocarditis in adults: a narrative review

Fulminant myocarditis (FM) is an uncommon syndrome characterized by sudden and severe hemodynamic compromise secondary to acute myocardial inflammation, often presenting as profound cardiogenic shock, life-threatening ventricular arrhythmias and/or electrical storm. FM may be refractory to conventional therapies and require mechanical circulatory support (MCS). The immune system has been recognized as playing a pivotal role in the pathophysiology of myocarditis, leading to an increased focus on immunosuppressive treatment strategies. Recent data have highlighted not only the fact that FM has significantly worse outcomes than non-FM, but that prognosis and management strategies of FM are heavily dependent on histological subtype, placing greater emphasis on the role of endomyocardial biopsy in diagnosis. The impact of subtype on severity and prognosis will likewise influence how aggressively the myocarditis is managed, including whether MCS is warranted. Many patients with refractory cardiogenic shock secondary to FM end up requiring MCS, with venoarterial extracorporeal membrane oxygenation demonstrating favorable survival rates, particularly when initiated prior to the development of multiorgan failure. Among the challenges facing the field are the need to more precisely identify immunopathophysiological pathways in order to develop targeted therapies, and the need to better optimize the timing and management of MCS to minimize complications and maximize outcomes.

Differences in Prognosis and Cardiac Function According to Required Percutaneous Mechanical Circulatory Support and Histological Findings in Patients With Fulminant Myocarditis: Insights From the CHANGE PUMP 2 Study

Background

Prognoses and long‐term cardiac function of patients with fulminant myocarditis have not been fully elucidated. Therefore, we clarified the prognoses and long‐term cardiac function according to required percutaneous mechanical circulatory support and histological findings among patients with fulminant myocarditis.

Methods and Results

We conducted a multicenter retrospective medical record review of 216 patients with fulminant myocarditis requiring percutaneous mechanical circulatory support. Sixty‐one patients were treated with intra‐aortic balloon pump or Impella alone, and 155 patients received veno‐arterial extracorporeal membrane oxygenation and were treated with or without intra‐aortic balloon pump or Impella. Histologically, 107 patients had lymphocytic myocarditis; 34, eosinophilic myocarditis; and 4, giant cell myocarditis. Freedom from composite end point (death, durable left ventricular assist device implantation, and heart transplantation) was 66% at 90 days, 62% at 1 year, and 57% at 6 years. Veno‐arterial extracorporeal membrane oxygenation use was associated with poor prognosis in the multivariable analysis (hazard ratio [HR], 5.27; 95% CI, 1.60–17.36). The eosinophilic myocarditis subgroup showed better prognosis (HR, 0.28; 95% CI, 0.10–0.80) compared with the lymphocytic myocarditis subgroup but not in the multivariable analysis. Ventricular tachycardia/ventricular fibrillation rhythm at admission, high C‐reactive protein level, and no endomyocardial biopsy were also associated with poor prognosis. The left ventricular ejection fraction at 1 year was ≤50% in 16% of patients and was lower in patients with eosinophilic myocarditis (median: 57.9% [48.8–65.0%]) than in those with lymphocytic myocarditis (65.0% [58.6–68.7%]) (P=0.036).

Conclusions

Patients with fulminant myocarditis who received veno‐arterial extracorporeal membrane oxygenation had a poor prognosis. Long‐term cardiac function was impaired in some patients, especially those with eosinophilic myocarditis.