Myocardial Injury and Altered Gene Expression Associated With SARS-CoV-2 Infection or mRNA Vaccination

COVID-19 and myocardial injury: Targeting elevated biomarkers for potential novel therapies

BACKGROUND

The prevalence of COVID-19 as the primary diagnosis among hospitalized patients with myocardial injury has increased during the pandemic and targeting elevated oxidant stress and inflammatory biomarkers may offer a potential role for novel therapies to improve outcomes.

METHODS

At a single VA Medical Center from January 1 through December 31, 2021, troponin assays from patients being evaluated in the Emergency Room for consideration of admission were analyzed and peak levels from each patient were considered abnormal if exceeding the Upper Reference Limit (URL). Among admitted patients with an elevated troponin level, ICD-10 diagnoses were categorized, biomarker elevations were recorded, and independent predictors of death in patients with COVID-19 were determined at a median of 6-months following admission.

RESULTS

Of 998 patients, 399 (40 %) had a negative troponin and were not included in the analysis. Additional patients with an elevated troponin were also excluded, either because they were not admitted (n = 68) or had a final diagnosis of Type 1 MI (n = 117). Of the remaining 414 patients with an elevated peak troponin, COVID-19 was the primary diagnosis in 43 patients (10 %) and was the 4th most common diagnosis of patients admitted with myocardial injury behind congestive heart failure, sepsis, and COPD or pneumonia. At a median of 6-months following admission, 18 (42 %) of the COVID-19 patients had died and independent predictors of death (Odd Ratio: Confidence Intervals) were age (1.18: 1.06‒1.37), Troponin level (Log 10 transformed) (16.54: 2.30‒266.65) and C-Reactive Protein (CRP) (1.30: 1.10‒1.65).

CONCLUSIONS

Newly diagnosed COVID-19 during the pandemic was a common cause of elevated troponin in hospitalized patients without a Type 1 MI. Age, peak troponin level and peak CRP level were independent predictors of poor outcomes and suggest a need to target these cardiac biomarkers, potentially with novel antioxidant or anti-inflammatory therapies.

Incidence and management of the main serious adverse events reported after COVID-19 vaccination

Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2n first appeared in Wuhan, China in 2019. Soon after, it was declared a pandemic by the World Health Organization. The health crisis imposed by a new virus and its rapid spread worldwide prompted the fast development of vaccines. For the first time in human history, two vaccines based on recombinant genetic material technology were approved for human use. These mRNA vaccines were applied in massive immunization programs around the world, followed by other vaccines based on more traditional approaches. Even though all vaccines were tested in clinical trials prior to their general administration, serious adverse events, usually of very low incidence, were mostly identified after application of millions of doses. Establishing a direct correlation (the cause-effect paradigm) between vaccination and the appearance of adverse effects has proven challenging. This review focuses on the main adverse effects observed after vaccination, including anaphylaxis, myocarditis, vaccine-induced thrombotic thrombocytopenia, Guillain-Barré syndrome, and transverse myelitis reported in the context of COVID-19 vaccination. We highlight the symptoms, laboratory tests required for an adequate diagnosis, and briefly outline the recommended treatments for these adverse effects. The aim of this work is to increase awareness among healthcare personnel about the serious adverse events that may arise post-vaccination. Regardless of the ongoing discussion about the safety of COVID-19 vaccination, these adverse effects must be identified promptly and treated effectively to reduce the risk of complications.

Sympathetic remodeling and altered angiotensin-converting enzyme 2 localization occur in patients with cardiac disease but are not exacerbated by severe COVID-19

PURPOSE

Remodeling of sympathetic nerves and ACE2 has been implicated in cardiac pathology, and ACE2 also serves as a receptor for SARS-CoV-2. However, there is limited histological knowledge about the transmural distribution of sympathetic nerves and the cellular localization and distribution of ACE2 in human left ventricles from normal or diseased hearts. Goals of this study were to establish the normal pattern for these parameters and determine changes that occurred in decedents with cardiovascular disease alone compared to those with cardiac pathology and severe COVID-19.

METHODS

We performed immunohistochemical analysis on sections of left ventricular wall from twenty autopsied human hearts consisting of a control group, a cardiovascular disease group, and COVID-19 ARDS, and COVID-19 non-ARDS groups.

RESULTS

Using tyrosine hydroxylase as a noradrenergic marker, we found substantial sympathetic nerve loss in cardiovascular disease samples compared to controls. Additionally, we found heterogeneous nerve loss in both COVID-19 groups. Using an ACE2 antibody, we observed robust transmural staining localized to pericytes in the control group. The cardiovascular disease hearts displayed regional loss of ACE2 in pericytes and regional increases in staining of cardiomyocytes for ACE2. Similar changes were observed in both COVID-19 groups.

CONCLUSIONS

Heterogeneity of sympathetic innervation, which occurs in cardiac disease and is not increased by severe COVID-19, could contribute to arrhythmogenesis. The dominant localization of ACE2 to pericytes suggests that these cells would be the primary target for potential cardiac infection by SARS-CoV-2. Regional changes in ACE2 staining by myocytes and pericytes could have complex effects on cardiac pathophysiology.

SARS-CoV-2 spike receptor-binding domain is internalized and promotes protein ISGylation in human induced pluripotent stem cell-derived cardiomyocytes

Although an increased risk of myocarditis has been observed after vaccination with mRNA encoding severe acute respiratory syndrome coronavirus 2 spike protein, its underlying mechanism has not been elucidated. This study investigated the direct effects of spike receptor-binding domain (S-RBD) on human cardiomyocytes differentiated from induced pluripotent stem cells (iPSC-CMs). Immunostaining experiments using ACE2 wild-type (WT) and knockout (KO) iPSC-CMs treated with purified S-RBD demonstrated that S-RBD was bound to ACE2 and internalized into the subcellular space in the iPSC-CMs, depending on ACE2. Immunostaining combined with live cell imaging using a recombinant S-RBD fused to the superfolder GFP (S-RBD-sfGFP) demonstrated that S-RBD was bound to the cell membrane, co-localized with RAB5A, and then delivered from the endosomes to the lysosomes in iPSC-CMs. Quantitative PCR array analysis followed by single cell RNA sequence analysis clarified that S-RBD-sfGFP treatment significantly upregulated the NF-kβ pathway-related gene (CXCL1) in the differentiated non-cardiomyocytes, while upregulated interferon (IFN)-responsive genes (IFI6, ISG15, and IFITM3) in the matured cardiomyocytes. S-RBD-sfGFP treatment promoted protein ISGylation, an ISG15-mediated post-translational modification in ACE2-WT-iPSC-CMs, which was suppressed in ACE2-KO-iPSC-CMs. Our experimental study demonstrates that S-RBD is internalized through the endolysosomal pathway, which upregulates IFN-responsive genes and promotes ISGylation in the iPSC-CMs.

Sex-specific differences in myocardial injury incidence after COVID-19 mRNA-1273 booster vaccination

AIMS

To explore the incidence and potential mechanisms of oligosymptomatic myocardial injury following COVID-19 mRNA booster vaccination.

METHODS AND RESULTS

Hospital employees scheduled to undergo mRNA-1273 booster vaccination were assessed for mRNA-1273 vaccination-associated myocardial injury, defined as acute dynamic increase in high-sensitivity cardiac troponin T (hs-cTnT) concentration above the sex-specific upper limit of normal on day 3 (48-96 h) after vaccination without evidence of an alternative cause. To explore possible mechanisms, antibodies against interleukin-1 receptor antagonist (IL-1RA), the SARS-CoV-2-nucleoprotein (NP) and -spike (S1) proteins and an array of 14 inflammatory cytokines were quantified. Among 777 participants (median age 37 years, 69.5% women), 40 participants (5.1%; 95% confidence interval [CI] 3.7-7.0%) had elevated hs-cTnT concentration on day 3 and mRNA-1273 vaccine-associated myocardial injury was adjudicated in 22 participants (2.8% [95% CI 1.7-4.3%]). Twenty cases occurred in women (3.7% [95% CI 2.3-5.7%]), two in men (0.8% [95% CI 0.1-3.0%]). Hs-cTnT elevations were mild and only temporary. No patient had electrocardiographic changes, and none developed major adverse cardiac events within 30 days (0% [95% CI 0-0.4%]). In the overall booster cohort, hs-cTnT concentrations (day 3; median 5, interquartile range [IQR] 4-6 ng/L) were significantly higher compared to matched controls (n = 777, median 3 [IQR 3-5] ng/L, p < 0.001). Cases had comparable systemic reactogenicity, concentrations of anti-IL-1RA, anti-NP, anti-S1, and markers quantifying systemic inflammation, but lower concentrations of interferon (IFN)-λ1 (IL-29) and granulocyte-macrophage colony-stimulating factor (GM-CSF) versus persons without vaccine-associated myocardial injury.

CONCLUSION

mRNA-1273 vaccine-associated myocardial injury was more common than previously thought, being mild and transient, and more frequent in women versus men. The possible protective role of IFN-λ1 (IL-29) and GM-CSF warrant further studies.

An extensive β1-adrenergic receptor gene signaling network regulates molecular remodeling in dilated cardiomyopathies

We investigated the extent, biologic characterization, phenotypic specificity, and possible regulation of a β1-adrenergic receptor-linked (β1-AR-linked) gene signaling network (β1-GSN) involved in left ventricular (LV) eccentric pathologic remodeling. A 430-member β1-GSN was identified by mRNA expression in transgenic mice overexpressing human β1-ARs or from literature curation, which exhibited opposite directional behavior in interventricular septum endomyocardial biopsies taken from patients with beta-blocker-treated, reverse remodeled dilated cardiomyopathies. With reverse remodeling, the major biologic categories and percentage of the dominant directional change were as follows: metabolic (19.3%, 81% upregulated); gene regulation (14.9%, 78% upregulated); extracellular matrix/fibrosis (9.1%, 92% downregulated); and cell homeostasis (13.3%, 60% upregulated). Regarding the comparison of β1-GSN categories with expression from 19,243 nonnetwork genes, phenotypic selection for major β1-GSN categories was exhibited for LV end systolic volume (contractility measure), ejection fraction (remodeling index), and pulmonary wedge pressure (wall tension surrogate), beginning at 3 months and persisting to study completion at 12 months. In addition, 121 lncRNAs were identified as possibly involved in cis-acting regulation of β1-GSN members. We conclude that an extensive 430-member gene network downstream from the β1-AR is involved in pathologic ventricular remodeling, with metabolic genes as the most prevalent category.

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.

Interaction of COVID-19 With Common Cardiovascular Disorders

The onset and widespread dissemination of the severe acute respiratory syndrome coronavirus-2 in late 2019 impacted the world in a way not seen since the 1918 H1N1 pandemic, colloquially known as the Spanish Flu. Much like the Spanish Flu, which was observed to disproportionately impact young adults, it became clear in the early days of the coronavirus disease 2019 (COVID-19) pandemic that certain groups appeared to be at higher risk for severe illness once infected. One such group that immediately came to the forefront and garnered international attention was patients with preexisting cardiovascular disease. Here, we examine the available literature describing the interaction of COVID-19 with a myriad of cardiovascular conditions and diseases, paying particular attention to patients diagnosed with arrythmias, heart failure, and coronary artery disease. We further discuss the association of acute COVID-19 with de novo cardiovascular disease, including myocardial infarction due to coronary thrombosis, myocarditis, and new onset arrhythmias. We will evaluate various biochemical theories to explain these findings, including possible mechanisms of direct myocardial injury caused by the severe acute respiratory syndrome coronavirus-2 virus at the cellular level. Finally, we will discuss the strategies employed by numerous groups and governing bodies within the cardiovascular disease community to address the unprecedented challenges posed to the care of our most vulnerable patients, including heart transplant recipients, end-stage heart failure patients, and patients suffering from acute coronary syndromes, during the early days and height of the COVID-19 pandemic.

Fulminant Myocarditis and Cardiogenic Shock Following COVID-19 Infection Versus COVID-19 Vaccination: A Systematic Literature Review

BACKGROUND

Myocarditis, diagnosed by symptoms and troponin elevation, has been well-described with COVID-19 infection, as well as shortly after COVID-19 vaccination. The literature has characterized the outcomes of myocarditis following COVID-19 infection and vaccination, but clinicopathologic, hemodynamic, and pathologic features following fulminant myocarditis have not been well-characterized. We aimed to compare clinical and pathological features of fulminant myocarditis requiring hemodynamic support with vasopressors/inotropes and mechanical circulatory support (MCS), in these two conditions.

METHODS

We analyzed the literature on fulminant myocarditis and cardiogenic shock associated with COVID-19 and COVID-19 vaccination and systematically reviewed all cases and case series where individual patient data were presented. We searched PubMed, EMBASE, and Google Scholar for "COVID", "COVID-19", and "coronavirus" in combination with "vaccine", "fulminant myocarditis", "acute heart failure", and "cardiogenic shock". The Student's t-test was used for continuous variables and the χ2 statistic was used for categorical variables. For non-normal data distributions, the Wilcoxon Rank Sum Test was used for statistical comparisons.

RESULTS

We identified 73 cases and 27 cases of fulminant myocarditis associated with COVID-19 infection (COVID-19 FM) and COVID-19 vaccination (COVID-19 vaccine FM), respectively. Fever, shortness of breath, and chest pain were common presentations, but shortness of breath and pulmonary infiltrates were more often present in COVID-19 FM. Tachycardia, hypotension, leukocytosis, and lactic acidosis were seen in both cohorts, but patients with COVID-19 FM were more tachycardic and hypotensive. Histologically, lymphocytic myocarditis dominated both subsets, with some cases of eosinophilic myocarditis in both cohorts. Cellular necrosis was seen in 44.0% and 47.8% of COVID-19 FM and COVID-19 vaccine FM, respectively. Vasopressors and inotropes were used in 69.9% of COVID-19 FM and in 63.0% of the COVID-19 vaccine FM. Cardiac arrest was observed more in COVID-19 FM (p = 0.008). Venoarterial extracorporeal membrane oxygenation (VA-ECMO) support for cardiogenic shock was also used more commonly in the COVID-19 fulminant myocarditis group (p = 0.0293). Reported mortality was similar (27.7%) and 27.8%, respectively) but was likely worse for COVID-19 FM as the outcome was still unknown in 11% of cases.

CONCLUSIONS

In the first series to retrospectively assess fulminant myocarditis associated with COVID-19 infection versus COVID-19 vaccination, we found that both conditions had a similarly high mortality rate, while COVID-19 FM had a more malignant course with more symptoms on presentation, more profound hemodynamic decompensation (higher heart rate, lower blood pressure), more cardiac arrests, and higher temporary MCS requirements including VA-ECMO. In terms of pathology, there was no difference in most biopsies/autopsies that demonstrated lymphocytic infiltrates and some eosinophilic or mixed infiltrates. There was no predominance of young males in COVID-19 vaccine FM cases, with male patients representing only 40.9% of the cohort.

Immune Response and Molecular Mechanisms of Cardiovascular Adverse Effects of Spike Proteins from SARS-CoV-2 and mRNA Vaccines

The SARS-CoV-2 (severe acute respiratory syndrome coronavirus responsible for the COVID-19 disease) uses the Spike proteins of its envelope for infecting target cells expressing on the membrane the angiotensin converting enzyme 2 (ACE2) enzyme that acts as a receptor. To control the pandemic, genetically engineered vaccines have been designed for inducing neutralizing antibodies against the Spike proteins. These vaccines do not act like traditional protein-based vaccines, as they deliver the message in the form of mRNA or DNA to host cells that then produce and expose the Spike protein on the membrane (from which it can be shed in soluble form) to alert the immune system. Mass vaccination has brought to light various adverse effects associated with these genetically based vaccines, mainly affecting the circulatory and cardiovascular system. ACE2 is present as membrane-bound on several cell types, including the mucosa of the upper respiratory and of the gastrointestinal tracts, the endothelium, the platelets, and in soluble form in the plasma. The ACE2 enzyme converts the vasoconstrictor angiotensin II into peptides with vasodilator properties. Here we review the pathways for immunization and the molecular mechanisms through which the Spike protein, either from SARS-CoV-2 or encoded by the mRNA-based vaccines, interferes with the Renin-Angiotensin-System governed by ACE2, thus altering the homeostasis of the circulation and of the cardiovascular system. Understanding the molecular interactions of the Spike protein with ACE2 and the consequent impact on cardiovascular system homeostasis will direct the diagnosis and therapy of the vaccine-related adverse effects and provide information for development of a personalized vaccination that considers pathophysiological conditions predisposing to such adverse events.

Safety of COVID-19 Vaccines in Patients with Autoimmune Diseases, in Patients with Cardiac Issues, and in the Healthy Population

The coronavirus disease 2019 (COVID-19) has been a challenge for the whole world since the beginning of 2020, and COVID-19 vaccines were considered crucial for disease eradication. Instead of producing classic vaccines, some companies pointed to develop products that mainly function by inducing, into the host, the production of the antigenic protein of SARS-CoV-2 called Spike, injecting an instruction based on RNA or a DNA sequence. Here, we aim to give an overview of the safety profile and the actual known adverse effects of these products in relationship with their mechanism of action. We discuss the use and safety of these products in at-risk people, especially those with autoimmune diseases or with previously reported myocarditis, but also in the general population. We debate the real necessity of administering these products with unclear long-term effects to at-risk people with autoimmune conditions, as well as to healthy people, at the time of omicron variants. This, considering the existence of therapeutic interventions, much more clearly assessed at present compared to the past, and the relatively lower aggressive nature of the new viral variants.