The mean age of the patient at diagnosis was 15.3?±?1.0 (range: 14–17) years, and all patients were male. Seven patients presented with myocarditis symptoms after their second vaccine dose, one patient presented with pericarditis symptoms after his first dose, and the other patient presented with myocarditis symptoms after his booster dose. The median time at presenting to the hospital was 3 (range: 2–22) days. Seven (77.7%) patients had abnormal electrocardiography (ECG) findings, and the most prevalent finding was diffuse ST-segment elevation. Initial cardiac MRI results were abnormal in all patients, where 8 (88.8%) patients had late gadolinium enhancement, and 5 (55.5%) had myocardial edoema. Three patients showed local left ventricular wall-motion abnormalities. In their follow-up MRIs 3–6?months later, myocardial edoema was present in 2 (28.5%) patients, while late gadolinium enhancement was present in all patients (7/7, 100%, 2 patients did not have control MRI time). Hypokinetic segments were still present in one of the 3 patients. No negative cardiac events were observed in the short-term follow-up of any patient.

  • 77.7% abnormal ECG findings (ST-elevation most common).
  • LGE on 88.8% of MRIs.
  • 55.5% myocardial edoema (excess fluid).
  • 100% LGE present at 3-6 month follow up.

The infection fatality rate of COVID-19 for those aged 0-19 documented by Pezzullo et al was 0.0003% while the risk of myocarditis from mRNA vaccination was found to be 1/2000-1/3000

https://www.tandfonline.com/doi/abs/10.1080/23744235.2022.2157478?