Clinical Considerations: Myocarditis and Pericarditis after Receipt of COVID-19 Vaccines Among Adolescents and Young Adults
Cases of myocarditis and pericarditis have rarely been observed following receipt of COVID-19 vaccines used in the United States. Evidence from multiple monitoring systems in the United States and around the globe support a causal association between mRNA COVID-19 vaccines (i.e., Moderna or Pfizer-BioNTech) and myocarditis and pericarditis.
Myocarditis is inflammation of the heart muscle, and pericarditis is inflammation of the lining outside the heart; myopericarditis is present when both myocarditis and pericarditis occur at the same time. In these conditions, inflammation occurs in response to an infection or some other trigger. CDC has published case definitions for myocarditis and pericarditis. The severity of cases of myocarditis and pericarditis can vary. CDC has published studies with clinical information about myocarditis and pericarditis after COVID-19 vaccination.
Cases of myocarditis and pericarditis have occurred most frequently in adolescent and young adult males within 7 days after receiving the second dose of an mRNA COVID-19 vaccine; however, cases have also been observed after dose 1 and booster doses.
Data from the clinical trials of the Novavax COVID-19 Vaccine and global vaccine safety monitoring systems suggest an increased risk of myocarditis and pericarditis following Novavax vaccination. Data from post-authorization monitoring of Janssen COVID-19 Vaccine (Johnson & Johnson) suggest a possible increased risk of myocarditis and pericarditis following Janssen vaccination.
Information on the clinical trials for the Novavax COVID-19 vaccine can be found here: U.S. clinical trial results show Novavax vaccine is safe and prevents COVID-19 | National Institutes of Health (NIH)
Information on the safety monitoring of the Janssen COVID-19 vaccine can be found here: Safety Monitoring of the Janssen (Johnson & Johnson) COVID-19 Vaccine — United States, March–April 2021 | MMWR (cdc.gov)
Guidance for Clinicians
- Report all cases of myocarditis and pericarditis post-COVID-19 vaccination to the Vaccine Adverse Event Reporting System (VAERS).
- Consider myocarditis and pericarditis in persons with acute chest pain, shortness of breath, or palpitations, particularly in adolescents and young adults. Younger children who have myocarditis or pericarditis may have non-specific symptoms such as irritability, vomiting, poor feeding, tachypnea (fast breathing), or lethargy.
- Ask about prior COVID-19 vaccination if you identify these symptoms, as well as relevant questions about medical, travel, and social history.
- For initial evaluation, consider an electrocardiogram (ECG), troponin level, and inflammatory markers such as C-reactive protein and erythrocyte sedimentation rate. In the setting of normal ECG, troponin, and inflammatory markers, myocarditis or pericarditis are unlikely.
- For suspected cases, consider consultation with cardiology specialists for assistance with cardiac evaluation and management. Evaluation and management may vary depending on the patient age, clinical presentation, potential causes, or practice preference of the provider.
- For follow-up of patients with myocarditis, consult the guidance from the American Heart Association and American College of Cardiology.
- It is important to evaluate patients to rule out other potential causes of myocarditis and pericarditis. Consider consultation with infectious disease and/or rheumatology specialists to assist in this evaluation.
- Where available, evaluate for potential causes of myocarditis and pericarditis, particularly acute COVID-19 illness, current SARS-CoV-2 infection (such as PCR testing), or prior SARS-CoV-2 infection (such as, detection of SARS-CoV-2 antibodies), as well as other viral causes (such as, enterovirus PCR and comprehensive respiratory viral pathogen testing).
- CDC recommends everyone ages 6 months and older get vaccinated as soon as possible to protect against COVID-19 and its potentially severe complications.
- If myocarditis or pericarditis is diagnosed after a COVID-19 vaccine dose, before giving additional doses, please refer to the latest guidance in the COVID-19 and myocarditis and pericarditis section of the Interim Clinical Considerations for Use of COVID-19 Vaccines web page.
- NIH materials on myocarditis and pericarditis
- Frequently asked questions about VAERS reporting for COVID-19 vaccines
- How to report an adverse event to VAERS