Hypersensitivity Myocarditis after COVID-19 mRNA Vaccination

Fulminant Myocarditis Temporally Associated with COVID-19 Vaccination

PURPOSE OF REVIEW

Coronavirus disease-2019 (COVID-19) vaccines have been related to rare cases of acute myocarditis, occurring between 1 in 10,000 and 1 in 100,000 individuals, approximately. Incidence of COVID-19 vaccine-associated myocarditis varies with age, sex, and type of vaccine. Although most patients with acute myocarditis temporally associated with COVID-19 vaccines have an uneventful course, a small subpopulation presents with cardiogenic shock (termed fulminant myocarditis [FM]). This review explored the prevalence, clinical presentation, management, and prognosis of COVID-19 vaccine-associated acute myocarditis, specifically focusing on FM and comparing patients with fulminant versus non-fulminant myocarditis.

RECENT FINDINGS

Cases of FM represent about 2-4% (0 to 7.5%) of COVID-19 vaccine-associated acute myocarditis cases, and mortality is around 1%, ranging between 0 and 4.4%. First, we identified 40 cases of FM up to February 2023 with sufficient granular data from case reports and case series of COVID-19 vaccine-associated acute myocarditis that occurred within 30 days from the last vaccine injection. This population was compared with 294 cases of non-fulminant acute myocarditis identified in the literature during a similar time. Patients with FM were older (48 vs. 27 years), had a larger proportion of women (58% vs. 9%), and mainly occurred after the first shot compared with non-fulminant cases (58% vs. 16%). The reported mortality was 27% (11 out of 40), in line with non-vaccine-associated fulminant myocarditis. These data were in agreement with 36 cases of FM from a large Korean registry. Herein, we reviewed the clinical features, imaging results, and histological findings of COVID-19 vaccine-associated fulminant myocarditis. In conclusion, COVID-19 vaccine-associated FM differs from non-fulminant forms, suggesting potential specific mechanisms in these rare and severe forms. Mortality in vaccine-associated FM remains high, in line with other forms of FM.

Cardiac magnetic resonance in histologically proven eosinophilic myocarditis

BACKGROUND

Eosinophilic myocarditis (EM) is a life-threatening acute heart disease. Cardiac magnetic resonance (CMR) excels in the assessment of myocardial diseases but CMR studies of EM are limited. We aimed to describe CMR findings in histologically proven EM.

METHODS

Patients with histologically proven EM seen at an academic center from 2000 through 2020 were identified. Of the 28 patients ascertained, 15 had undergone CMR for diagnosis and constitute our study cohort.

RESULTS

The patients, aged 51 ± 17 years, presented with fever (53%), dyspnea (47%), chest pain (53%), heart block (20%), and blood eosinophilia (60%). On CMR, all 15 patients had myocardial edema with 10 of them (67%) having abnormally high left ventricular (LV) mass as well. LV ejection fraction measured < 50% in 11 patients (73%) and < 30% in 2 (13%), but only 6 (40%) had dilated LV size. Eight patients (53%) had pericardial effusion. LV late gadolinium enhancement (LGE) was found in all but one patient (13/14; 93%). LGE was always multifocal and subendocardial but could involve any myocardial layer. Patients with necrotizing EM by histopathology (n = 6) had higher LGE mass (32.1 ± 16.6% vs 14.5 ± 7.7%, p = 0.050) and more LV segments with LGE (15 ± 2 vs 9 ± 3 out of 17, p = 0.003) than patients (n = 9) without myocyte necrosis. Two patients had LV thrombosis accompanying widespread subendocardial LGE.

CONCLUSIONS

In EM, CMR shows myocardial edema and LGE that is typically subendocardial but can involve any myocardial layer. The left ventricle is often non-dilated with moderate-to-severe systolic dysfunction. Pericardial effusion is common. Necrotizing EM presents with extensive myocardial LGE on CMR.

Host-microbe tryptophan partitioning in cardiovascular diseases

The functional interdependencies between the molecular components of a biological process demand for a network medicine platform that integrates systems biology and network science, to explore the interactions among biological components in health and disease. Access to large-scale omics datasets (genomics, transcriptomics, proteomics, metabolomics, metagenomics, phenomics, etc.) has significantly advanced our opportunity along this direction. Studies utilizing these techniques have begun to provide us with a deeper understanding of how the interaction between the intestinal microbes and their host affects the cardiovascular system in health and disease. Within the framework of a multiomics network approach, we highlight here how tryptophan metabolism may orchestrate the host-microbes interaction in cardiovascular diseases and the implications for precision medicine and therapeutics, including nutritional interventions.

Myocarditis and COVID-19 related issues

The recent COVID-19 (Coronavirus Disease 2019) pandemic by SARS-CoV2 infection has caused millions of deaths and hospitalizations across the globe. In the early pandemic phases, the infection had been initially considered a primary pulmonary disease. However, increasing evidence has demonstrated a wide range of possible cardiac involvement. Most of systemic and cardiac damage is likely sustained by a complex interplay between inflammatory, immune-related and thrombotic mechanisms. Biventricular failure and myocardial damage with elevation of cardiac biomarkers have been reported in COVID-19 patients, although histological demonstration of acute myocarditis has been rarely documented. Indeed while cardiac magnetic resonance findings include different patterns of myocardial involvement in terms of late gadolinium enhancement, histological data from necropsy and endomyocardial biopsy showed peculiar inflammatory patterns, mostly composed by macrophages. On the other hand COVID-19 vaccines based on mRN technology have been also associated with increased risk of myocarditis. COVID-19 and mRNA vaccine-related myocarditis present different clinical and imaging presentations and recent data suggest the presence of distinctive immunological mechanisms involved.

Vaccination-Associated Myocarditis and Myocardial Injury

SARS-CoV-2 vaccine-associated myocarditis/myocardial injury should be evaluated in the contexts of COVID-19 infection, other types of viral myocarditis, and other vaccine-associated cardiac disorders. COVID-19 vaccine-associated myocardial injury can be caused by an inflammatory immune cell infiltrate, but other etiologies such as microvascular thrombosis are also possible. The clinical diagnosis is typically based on symptoms and cardiac magnetic resonance imaging. Endomyocardial biopsy is confirmatory for myocarditis, but may not show an inflammatory infiltrate because of rapid resolution or a non-inflammatory etiology. Myocarditis associated with SARS-COVID-19 vaccines occurs primarily with mRNA platform vaccines, which are also the most effective. In persons aged >16 or >12 years the myocarditis estimated crude incidences after the first 2 doses of BNT162b2 and mRNA-1273 are approximately 1.9 and 3.5 per 100 000 individuals, respectively. These rates equate to excess incidences above control populations of approximately 1.2 (BNT162b2) and 1.9 (mRNA-1273) per 100 000 persons, which are lower than the myocarditis rate for smallpox but higher than that for influenza vaccines. In the studies that have included mRNA vaccine and SARS-COVID-19 myocarditis measured by the same methodology, the incidence rate was increased by 3.5-fold over control in COVID-19 compared with 1.5-fold for BNT162b2 and 6.2-fold for mRNA-1273. However, mortality and major morbidity are less and recovery is faster with mRNA vaccine-associated myocarditis compared to COVID-19 infection. The reasons for this include vaccine-associated myocarditis having a higher incidence in young adults and adolescents, typically no involvement of other organs in vaccine-associated myocarditis, and based on comparisons to non-COVID viral myocarditis an inherently more benign clinical course.

Delayed presentation of biopsy-proven eosinophilic myocarditis following COVID-19 mRNA vaccine

Myopericarditis associated with COVID-19 mRNA vaccines has been recognized as an uncommon adverse reaction, especially among young, healthy adult males. Eosinophilic myocarditis is a rare form of inflammation reflecting a hypersensitivity reaction following an inciting event commonly caused by drugs including vaccines. Eosinophilic myocarditis, a subtype of myocarditis, is characterized by eosinophilic myocardial infiltrates. It is usually accompanied by systemic eosinophilia in the form of a drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome and is rarely associated with myocyte fibrosis and/or necrosis. In this report, we present a case of biopsy-proven eosinophilic myocarditis in a 24-year-old male patient, likely secondary to COVID-19 mRNA vaccination. To our knowledge, this is the first report to describe delayed eosinophilic myocarditis following the COVID-19 mRNA vaccine. Clinicians should be aware of possible delayed presentation to avoid associated morbidity.

Evaluation of Autoantibody Binding to Cardiac Tissue in Multisystem Inflammatory Syndrome in Children and COVID-19 Vaccination-Induced Myocarditis

Importance

Cardiac dysfunction and myocarditis have emerged as serious complications of multisystem inflammatory syndrome in children (MIS-C) and vaccines against SARS-CoV-2. Understanding the role of autoantibodies in these conditions is essential for guiding MIS-C management and vaccination strategies in children.

Objective

To investigate the presence of anticardiac autoantibodies in MIS-C or COVID-19 vaccine-induced myocarditis.

Design, Setting, and Participants

This diagnostic study included children with acute MIS-C or acute vaccine myocarditis, adults with myocarditis or inflammatory cardiomyopathy, healthy children prior to the COVID-19 pandemic, and healthy COVID-19 vaccinated adults. Participants were recruited into research studies in the US, United Kingdom, and Austria starting January 2021. Immunoglobulin G (IgG), IgM, and IgA anticardiac autoantibodies were identified with immunofluorescence staining of left ventricular myocardial tissue from 2 human donors treated with sera from patients and controls. Secondary antibodies were fluorescein isothiocyanate-conjugated antihuman IgG, IgM, and IgA. Images were taken for detection of specific IgG, IgM, and IgA deposits and measurement of fluorescein isothiocyanate fluorescence intensity. Data were analyzed through March 10, 2023.

Main Outcomes and Measures

IgG, IgM and IgA antibody binding to cardiac tissue.

Results

By cohort, there were a total of 10 children with MIS-C (median [IQR] age, 10 [13-14] years; 6 male), 10 with vaccine myocarditis (median age, 15 [14-16] years; 10 male), 8 adults with myocarditis or inflammatory cardiomyopathy (median age, 55 [46-63] years; 6 male), 10 healthy pediatric controls (median age, 8 [13-14] years; 5 male), and 10 healthy vaccinated adults (all older than 21 years, 5 male). No antibody binding above background was observed in human cardiac tissue treated with sera from pediatric patients with MIS-C or vaccine myocarditis. One of the 8 adult patients with myocarditis or cardiomyopathy had positive IgG staining with raised fluorescence intensity (median [IQR] intensity, 11 060 [10 223-11 858] AU). There were no significant differences in median fluorescence intensity in all other patient cohorts compared with controls for IgG (MIS-C, 6033 [5834-6756] AU; vaccine myocarditis, 6392 [5710-6836] AU; adult myocarditis or inflammatory cardiomyopathy, 5688 [5277-5990] AU; healthy pediatric controls, 6235 [5924-6708] AU; healthy vaccinated adults, 7000 [6423-7739] AU), IgM (MIS-C, 3354 [3110-4043] AU; vaccine myocarditis, 3843 [3288-4748] AU; healthy pediatric controls, 3436 [3313-4237] AU; healthy vaccinated adults, 3543 [2997-4607] AU) and IgA (MIS-C, 3559 [2788-4466] AU; vaccine myocarditis, 4389 [2393-4780] AU; healthy pediatric controls, 3436 [2425-4077] AU; healthy vaccinated adults, 4561 [3164-6309] AU).

Conclusions and Relevance

This etiological diagnostic study found no evidence of antibodies from MIS-C and COVID-19 vaccine myocarditis serum binding cardiac tissue, suggesting that the cardiac pathology in both conditions is unlikely to be driven by direct anticardiac antibody-mediated mechanisms.

Short term outcome of myocarditis and pericarditis following COVID-19 vaccines: a cardiac magnetic resonance imaging study

To evaluate clinical and cardiac magnetic resonance (CMR) short-term follow-up (FU) in patients with vaccine-associated myocarditis, pericarditis or myo-pericarditis (VAMP) following COVID-19 vaccination. We retrospectively analyzed 44 patients (2 women, mean age: 31.7 ± 15.1 years) with clinical and CMR manifestations of VAMP, recruited from 13 large tertiary national centers. Inclusion criteria were troponin raise, interval between the last vaccination dose and onset of symptoms < 25 days and symptoms-to-CMR < 20 days. 29/44 patients underwent a short-term FU-CMR with a median time of 3.3 months. Ventricular volumes and CMR findings of cardiac injury were collected in all exams. Mean interval between the last vaccination dose and the onset of symptoms was 6.2 ± 5.6 days. 30/44 patients received a vaccination with Comirnaty, 12/44 with Spikevax, 1/44 with Vaxzevria and 1/44 with Janssen (18 after the first dose of vaccine, 20 after the second and 6 after the "booster" dose). Chest pain was the most frequent symptom (41/44), followed by fever (29/44), myalgia (17/44), dyspnea (13/44) and palpitations (11/44). At baseline, left ventricular ejection fraction (LV-EF) was reduced in 7 patients; wall motion abnormalities have been detected in 10. Myocardial edema was found in 35 (79.5%) and LGE in 40 (90.9%) patients. Clinical FU revealed symptoms persistence in 8/44 patients. At FU-CMR, LV-EF was reduced only in 2 patients, myocardial edema was present in 8/29 patients and LGE in 26/29. VAMPs appear to have a mild clinical presentation, with self-limiting course and resolution of CMR signs of active inflammation at short-term follow-up in most of the cases.

Comparison of COVID-19 Vaccine-Associated Myocarditis and Viral Myocarditis Pathology

The COVID-19 pandemic has led to significant loss of life and severe disability, justifying the expedited testing and approval of messenger RNA (mRNA) vaccines. While found to be safe and effective, there have been increasing reports of myocarditis after COVID-19 mRNA vaccine administration. The acute events have been severe enough to require admission to the intensive care unit in some, but most patients fully recover with only rare deaths reported. The pathways involved in the development of vaccine-associated myocarditis are highly dependent on the specific vaccine. COVID-19 vaccine-associated myocarditis is believed to be primarily caused by uncontrolled cytokine-mediated inflammation with possible genetic components in the interleukin-6 signaling pathway. There is also a potential autoimmune component via molecular mimicry. Many of these pathways are similar to those seen in viral myocarditis, indicating a common pathophysiology. There is concern for residual cardiac fibrosis and increased risk for the development of cardiomyopathies later in life. This is of particular interest for patients with congenital heart defects who are already at increased risk for fibrotic cardiomyopathies. Though the risk for vaccine-associated myocarditis is important to consider, the risk of viral myocarditis and other injury is far greater with COVID-19 infection. Considering these relative risks, it is still recommended that the general public receive vaccination against COVID-19, and it is particularly important for congenital heart defect patients to receive vaccination for COVID-19.

Reports of New and Recurrent Keratitis following mRNA-based COVID-19 Vaccination

PURPOSE

As ophthalmic side effects of messenger RNA (mRNA)-based COVID-19 vaccination are not well understood, it is crucial to document and report such instances should they occur.

METHODS

In this observational case series, we report nine patients (55.6% male, mean age 58.9) who received either the BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) COVID-19 vaccinations from January to June of 2021, and presented with symptoms of keratitis within 14 days. All patients underwent slit-lamp examination and histories were taken.

RESULTS

Most subjects (66.7%) had a history of corneal inflammatory diseases and resolved under antiviral and/or steroidal treatment. Patients who reported symptoms after their second vaccine dose presented earlier than those who reported symptoms after the first dose (mean 4.4 days vs 10.5 days, respectively).

CONCLUSIONS

The immunological reaction following mRNA-based COVID-19 vaccinations may trigger new-onset or reactivation of keratitis, though causality cannot be proven. Despite its rarity, clinicians should be aware of this possible complication and be prepared to treat.

Remarks on Myocarditis Associated with COVID-19 Infection and Myocarditis Following mRNA COVID-19 Vaccination

COVID-19 virus infection is responsible for one of the worst reported pandemics as of August 2022 [...].

An autopsy case report of aortic dissection complicated with histiolymphocytic pericarditis and aortic inflammation after mRNA COVID-19 vaccination

A male in his 90 s consulted a doctor because he experienced several days of general fatigue and dyspnea. He was diagnosed with heart failure, and diuretic medications taken for 3 days relieved his symptoms. However, he was found dead on the morning of the fourth day after consultation. He had received a third dose of coronavirus disease 2019 (COVID-19) vaccine approximately 2 weeks before death. An autopsy revealed dissection of the ascending aorta and pericardial hemotamponade. The heart showed a white villous surface, and the pericardium was fibrously thick. Microscopic examination revealed pericarditis with predominantly macrophage and lymphocyte infiltration. These histological findings were compatible with those of post-vaccination myocarditis. To the best of our knowledge, histopathologically proven pericarditis after COVID-19 vaccination has not been reported. In the present case, extended inflammation of the aortic adventitia was a possible cause of aortic wall fragility followed by dissection.

Cardiac MRI Findings in COVID-19 Vaccine-Related Myocarditis: A Pooled Analysis of 468 Patients

Understanding the pattern and severity of myocarditis caused by the coronavirus disease 2019 (COVID-19) vaccine is imperative for improving the care of the patients, and cardiac evaluation by MRI plays a key role in this regard. Our systematic review and meta-analysis aimed to summarize cardiac MRI findings in COVID-19 vaccine-related myocarditis. We performed a comprehensive systematic review of literature in PubMed, Scopus, and Google Scholar databases using key terms covering COVID-19 vaccine, myocarditis, and cardiac MRI. Individual-level patient data (IPD) and aggregated-level data (AD) studies were pooled through a two-stage analysis method. For this purpose, all IPD were first gathered into a single data set and reduced to AD, and then this AD (from IPD studies) was pooled with existing AD (from the AD studies) using fixed/random effect models. I² was used to assess the degree of heterogeneity, and the prespecified level of statistical significance (P value for heterogeneity) was <0.1. Based on meta-analysis of 102 studies (n = 468 patients), 79% (95% confidence interval [CI]: 54%-97%) of patients fulfilled Lake Louise criteria (LLC) for diagnosis of myocarditis. Cardiac MRI abnormalities included elevated T2 in 72% (95% CI: 50%-90%), myocardial late gadolinium enhancement (LGE) in 93% (95% CI: 83%-99%; nearly all with a subepicardial and/or midwall pattern), impaired left ventricular ejection fraction (LVEF) (<50%) in 4% (95% CI: 1.0%-9.0%). Moreover, elevated T1 and extracellular volume fraction (ECV) (>30), reported only by some IPD studies, were detected in 74.5% (76/102) and 32% (16/50) of patients, respectively. In conclusion, our findings may suggest that over two-thirds of patients with clinically suspected myocarditis following COVID-19 vaccination meet the LLC. COVID-19 vaccine-associated myocarditis may show a similar pattern compared to other acute myocarditis entities. Notably, preserved LVEF is probably a common finding in these patients. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 3.

An autopsy case report of fulminant myocarditis: Following mRNA COVID-19 vaccination

There have been few case reports on fatal outcomes in patients with acute myocarditis after mRNA coronavirus disease 2019 (COVID-19) vaccination. In most cases of myocarditis after mRNA COVID-19 vaccination, the myocarditis is mild, and the prognosis is good. Here we report an autopsy case of fulminant myocarditis following mRNA COVID-19 vaccination.

Learning objective

The global distribution of the mRNA coronavirus disease 2019 vaccine requires consideration of appropriate treatment for postvaccination myocarditis. Eosinophil-mediated immunological injury to cardiomyocytes can be involved in the cause of fulminant inflammation from the pathological findings of postvaccination myocarditis.

Establishing the Pharmacokinetics of Genetic Vaccines is Essential for Maximising their Safety and Efficacy

In a typical course of drug development, thorough pharmacokinetic (PK) studies are essential for the determination of drug biodistribution, dosage and efficacy without toxicity. For vaccines, however, unless a new formulation component is used, most regulatory agencies rule out the need for studying the biodistribution of the vaccine antigenic material per se, and only dose-immunogenicity studies are performed. This is because traditional vaccines are meant to directly induce immunogenicity by locally recruiting immunocytes that will carry on with the pursuing immunogenic processes. Thus, the clinical outcome from traditional vaccines is determined mainly by an immunological response phase. Yet, the case is significantly different for the emergent genetic vaccines (vectorised DNA or mRNA vaccines), where the clinical outcome is dependent on a combination of two major response phases: a pharmacological phase that involves biodistribution, assimilation, gene translation and epitope(s) presentation, followed by an immunological phase, which is similar to that of traditional vaccines. From a mathematical perspective, processes involved in drug administration are typically subject to inter- and intra-patient statistical distributions like most physiological processes. Therefore, the clinical outcome after administering genetic vaccines obeys a statistical probability distribution combined of the sum of two major response probability distributions, pharmacological and immunological. This implies that the variance coefficient of the summed response probability distributions has a larger value than the variance of each underlying distribution. In other words, due to the multi-phased mode of action of genetic vaccines, their clinical outcome has more variability than that of traditional vaccines. This observation points toward the necessity for regulating genetic vaccines in a similar manner to bio-therapeutics to ensure better efficacy and safety. A structural PK model is provided to predict the sources of variability, biodistribution and dose optimisation.