Myocarditis/Pericarditis after mRNA COVID-19 Vaccines
mRNA vaccines
- A small increased risk of myocarditis and/or pericarditis with Pfizer or Moderna, compared with unvaccinated people.
- The risk – Moderna>Pfizer.
- commonly in males under 40 years of age
- commonly after the second vaccine dose.
- risk in children aged 5-11 years is significantly lower than in adolescents aged 12-17 years.
- No specific precautions are recommended for people with a history of chronic cardiovascular conditions, including coronary artery disease, myocardial infarction, stable heart failure, arrhythmias, rheumatic heart disease (RHD), Kawasaki Disease, congenital heart disease, cardiomyopathy, or cardiac transplant, and in people with implantable cardiac devices.
Symptoms and outcomes
- typically appear within 1-5 days of a COVID-19 vaccine dose
| Myocarditis | Pericarditis | |
|---|---|---|
| Symptoms | Chest pain, pressure or discomfortPalpitationsShortness of breathNon-specific symptoms e.g. fatigue | Chest pain which may be sharp, worse when lying down, and alleviated when sitting up and leaning forwardPain on deep inspiration |
| Signs | May have normal examinationTachycardiaSevere myocarditis: signs of cardiac dysfunction e.g. third heart sound, oedema | Pericardial rub on auscultation |
Assessment of possible myocarditis or pericarditis in a primary care setting
- Initial investigations can be performed in the primary care setting, based on clinical judgement, if:
- the patient is not acutely unwell
- has mild symptoms
- the referring practice can obtain and review all the results of initial investigations within 12 hours.
- Patients with significant clinical suspicion of myocarditis and/or pericarditis should immediately be referred to ED if any of the following apply:
- they are acutely unwell(any age)
- they have suspicious and/or concerning chest pain and are aged ≥ 30 years
- they have abnormal ECG findings
- initial investigations cannot be performed and reviewed within 12 hours
Investigations:
| Investigation | Findings | |
|---|---|---|
| 12- lead ECG | Myocarditis | Pericarditis |
| ST or T-wave abnormalities#, Q waves Premature atrial complexesPremature ventricular complexesCan be normal | Widespread ST elevation (typically concave up)PR depressionSmall QRS (reflecting pericardial effusion) Can be normal or atypical | |
| Troponin | Commonly raised, however absence of elevation* does not exclude myocarditis | May be increased (suggestive of myopericarditis) |
| Inflammatory markers: CRP, ESR | Commonly raised (although nonspecific) | Commonly raised (although nonspecific) |
| Chest X-ray (PA) | Heart size can be normal or enlarged (in children this is defined as cardiothoracic ratio >0.5) | Typically normalRarely, large pericardial effusion can lead to cardiomegaly |
assessment of possible vaccine-induced pericarditis/myocarditis in children and adolescents presenting to the ED
Future vaccine dose recommendations:
- Further doses of COVID-19 vaccine can be given to people
- Clinical diagnosis of Pericarditis but with normal ECG, troponin, and inflammatory makers and symptom-free for at least 6 weeks
- Confirmed Pericarditis and abnormal investigation results, the need and choice of further doses is informed by age and sex (see below)
- Confirmed myocarditis attributed to a COVID-19 vaccine, further doses should be considered on a case-by-case basis, and usually deferred until recovery from symptoms.
- For those ≥18 years, Novavax or AstraZeneca may be suitable.
Approach to revaccination in people with pericarditis attributed to an mRNA COVID-19 vaccine
* SIS = specialist immunisation service;
^ AZ & NVX not licensed for <18yo;
% Risk appears lowers following AZ and risk is not yet known for NVX
Brighton Collaboration Case Definitions for Pericarditis
