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.

Recurrent ventricular tachycardia in a patient with COVID-19 vaccine-associated myocarditis: a case report.

Background: The development of coronavirus disease 2019 (COVID-19) vaccine-associated myocarditis has been reported. Most of the reported cases are mild, with quick clinical recovery and excellent short-term outcomes. Cases of COVID-19 vaccine-associated myocarditis presenting with sustained ventricular tachycardia (VT) are rare. Case Description: A 46-year-old male patient with no prior cardiac history presented following two episodes of syncope. Two days earlier, he had received his second dose of COVID-19 mRNA vaccine (Pfizer)-first dose was administered three weeks earlier. He had an episode of VT while in the emergency room. His cardiac magnetic resonance imaging (MRI) findings were consistent with myocarditis. He was eventually diagnosed with COVID-19 vaccine-associated myocarditis after all other work up were unremarkable [echocardiogram, coronary angiogram, diagnostic electrophysiology study and later 18F-fluorodeoxyglucose (FDG) metabolism cardiac sarcoid positron emission tomography (PET) study]. An implantable cardiac monitor was implanted to monitor for recurrence of VT. Seven months after initial presentation, he had recurrent VT and he underwent implantation of an implantable cardioverter defibrillator (ICD). He has received appropriate ICD therapies on account of recurrent VT and he is currently maintained on an antiarrhythmic medication. Conclusions: Excellent short-term outcomes have been reported in patients with COVID-19 vaccine associated myocarditis. Our case shows that long-term outcomes may not be benign in everyone, particularly in those who develop myocardial scar.

COVID-19 Vaccine-Induced Acute Perimyocarditis: A Case Report.

Perimyocarditis is the inflammation of the pericardium along with the myocardium. Presentation is similar to acute pericarditis, but it is associated with myocardial damage, leading to an elevation in serum troponin and a left ventricular dysfunction (manifested as an ejection fraction of less than 55 percent). Perimyocarditis is mostly managed like acute myocarditis. Etiology is generally idiopathic and likely secondary to viral infections. Cases of vaccine-associated myocarditis have been infrequently reported in past, most recently with the COVID-19 mRNA vaccine. We present a rare case of a young healthy adolescent male who developed perimyocarditis after the first booster dose of the COVID-19 mRNA vaccine.

Severe Myocarditis in a Female Following mRNA-1273 Vaccine: A Case Report and Review of the Literature.

Myocarditis was recently described as one of the complications secondary to COVID-19 vaccination. We present a 38-year-old lady diagnosed with vaccine-related myocarditis a few days after receiving the mRNA-1273 vaccine. We also summarize what is reported in the literature about the association between COVID-19 vaccination and myocarditis. In conclusion, COVID-19 immunization appears to be associated with significantly fewer adverse outcomes than COVID-19 infection among all age groups.

A case of vaccine-associated myocarditis following pneumococcal immunization leading to acute mitral regurgitation.

Vaccine-associated myocarditis (VAM) is a rare entity but can result in potentially serious sequelae if left untreated. However, the mechanisms of the complications of VAM and its treatment remain unclear. Herein, we report the first case of VAM related to pneumococcal immunization, presenting as a local and systemic inflammatory reaction, in which the patient developed significant secondary mitral regurgitation, resulting in acute heart failure. Finally, the patient recovered completely following corticosteroid treatment. This case highlights the value of cardiac magnetic resonance and the pitfall of endomyocardial biopsy in establishing the definitive diagnosis of VAM and emphasizes the importance of optimal management in understanding the mechanism and instituting the treatment for secondary mitral regurgitation caused by VAM.

Myocarditis Following Coronavirus Disease 2019 mRNA Vaccine: A Case Series and Incidence Rate Determination.

BACKGROUND: Myocarditis following coronavirus disease 2019 (COVID-19) mRNA vaccines (Pfizer-BioNTech and Moderna) has been increasingly reported. Incidence rates in the general population are lacking, with pericarditis rather than myocarditis diagnostic codes being used to estimate background rates. This comparison is critical for balancing the risk of vaccination with the risk of no vaccination. METHODS: A retrospective case series was performed using the Mayo Clinic COVID-19 Vaccine Registry. We measured the incidence rate ratio (IRR) for myocarditis temporally related to COVID-19 mRNA vaccination compared with myocarditis in a comparable population from 2016 through 2020. Clinical characteristics and outcomes of the affected patients were collected. A total of 21 individuals were identified, but ultimately 7 patients met the inclusion criteria for vaccine-associated myocarditis. RESULTS: The overall IRR of COVID-19-related myocarditis was 4.18 (95% confidence interval [CI], 1.63-8.98), which was entirely attributable to an increased IRR among adult males (IRR, 6.69; 95% CI, 2.35-15.52) compared with females (IRR 1.41; 95% CI, .03-8.45). All cases occurred within 2 weeks of a dose of the COVID-19 mRNA vaccine, with the majority occurring within 3 days (range, 1-13) following the second dose (6 of 7 patients, 86%). Overall, cases were mild, and all patients survived. CONCLUSIONS: Myocarditis is a rare adverse event associated with COVID-19 mRNA vaccines. It occurs in adult males with significantly higher incidence than in the background population. Recurrence of myocarditis after a subsequent mRNA vaccine dose is not known at this time.

Follow-up cardiac magnetic resonance in children with vaccine-associated myocarditis.

Myocarditis is a rare complication of the COVID-19 mRNA vaccine. We previously reported a case series of 15 adolescents with vaccine-associated myocarditis, 87% of whom had abnormalities on initial cardiac magnetic resonance (CMR), including late gadolinium enhancement (LGE) in 80%. We performed follow-up CMRs to determine the trajectory of myocardial recovery and better understand the natural history of vaccine-associated myocarditis. Case series of patients age < 19 years admitted to Boston Children's Hospital with acute vaccine-associated myocarditis following the BNT162b2 vaccine who had abnormal CMR at the time of initial presentation, and underwent follow-up testing. CMR assessment included left ventricular (LV) ejection fraction, T2-weighted myocardial imaging, LV global native T1, LV global T2, extracellular volume (ECV), and late gadolinium enhancement (LGE). Ten patients (9 male, median age 15 years) with vaccine-associated myocarditis underwent follow-up CMR at a median of 92 days (range 76-119) after hospital discharge. LGE was persistent in 80% of patients, though improved from prior in all cases. Two patients (20%) had abnormal LV global T1 at presentation, which normalized on follow-up. ECV decreased between acute presentation and follow-up in 6/10 patients; it remained elevated at follow-up in 1 patient and borderline in 3 patients. CONCLUSION: CMR performed ~3 months after admission for COVID-19 vaccine-associated myocarditis showed improvement of LGE in all patients, but persistent in the majority. Follow-up CMR 6-12 months after acute episode should be considered to better understand the long-term cardiac risks. WHAT IS KNOWN: • Myocarditis is a rare side effect of COVID-19 mRNA vaccine. •Late gadolinium enhancement is present on most cardiac magnetic resonance at the time of acute presentation. WHAT IS NEW: •Late gadolinium enhancement improved on all repeat cardiac magnetic resonance at 3-month follow-up. •Most patients still had a small amount of late gadolinium enhancement, the clinical significance of which is yet to be determined.

COVID-19 mRNA Vaccine-Associated Myocarditis.

Coronavirus disease 2019 (COVID-19) has been reported to cause cardiovascular complications including myocarditis, pericardial effusion, pericarditis, and arrhythmias. With the introduction of the vaccine, there have been reports of myocarditis possibly associated with the mRNA COVID-19 vaccine. We report a case of cardiac involvement following the second dose of Pfizer-BioNTech COVID-19 vaccine in a young male. A healthy 24-year-old male presented to the emergency department with complaints of non-radiating mid-sternal chest pain and pressure. He noticed his symptoms started six hours after he received the second dose of Pfizer COVID vaccine. Laboratory tests revealed elevated cardiac troponin I-CtNI levels. Computed tomography angiography of the chest did not show evidence of pulmonary embolism. Given his presentation of acute chest pain associated with elevated troponin levels, a coronary angiogram was performed which revealed normal coronary arteries. He was subsequently treated for acute peri-myocarditis with colchicine, non-steroidal anti-inflammatory drugs (NSAIDs), and beta-blockers for tachycardia and the prevention of arrhythmia. Although rare, clinicians should be aware of the risk for myocarditis and pericarditis, which should be considered in individuals presenting with chest pain within a week after vaccination, especially in the younger population. Although the long-term risk in these patients is uncertain, early diagnosis and treatment are key to minimizing complications.