Myocarditis is inflammation of the heart muscle. Pericarditis is inflammation of the outer lining of the heart.
Myocarditis and pericarditis are most commonly caused by a virus.
Symptoms:
Chest pain (common)
Shortness of breath
Arrhythmias (rhythm disturbances of the heart) (less common): e.g. Palpitations (rapid heartbeat, fluttering, or pounding heart)
Lightheadedness/fainting
Ankle swelling (edema)
Myocarditis and pericarditis should be suspected in a young person with no other cardiovascular risks who presents with cardiovascular symptoms.
The first test usually an electrocardiogram (EKG) which tests the electrical activity of the heart and a blood test (usually Troponin and other cardiac enzymes) to look for signs of cardiac injury. If these are abnormal, an echocardiogram should be performed. Sometime, a cardiac MRI or even a heart biopsy may be needed in severe cases.
Observation:
It has been reported that myocarditis and pericarditis may occur following vaccines including mRNA COVID-19 vaccines (i.e., Pfizer-BioNTech, Moderna). However, the rate is very low.
It is better to get the vaccine than not to get the vaccine. The reason is that the actual infection is always worse than the possible consequence of the vaccine.
Who is at higher risk:
Confirmed cases have occurred:
- Mostly in male adolescents and young adults age 16 years or older
- More often after getting the second dose than after the first dose of one of these two mRNA COVID-19 vaccines (i.e., Pfizer-BioNTech, Moderna)
- Typically, within several days after COVID-19 vaccination
How common?
The risk of that happening is only 1 in 100,000 vaccines. In contrast, the risk of actually getting myocarditis or pericarditis from the virus itself is about 1-2%. A much higher number. The known and potential benefits of COVID-19 vaccination outweigh the known and potential risks, including the possible risk of myocarditis or pericarditis. Therefore, we strongly recommend that everyone get the vaccine and minimize their risk. According to the CDC, getting vaccinated is the best way to help protect yourself and your family from COVID-19.
What causes these complications?
The cause of this is not yet known. It is likely related to an immune reaction to the components of the vaccine which is also what is needed to protect people from the virus itself.
Outcome:
Myocarditis and pericarditis are rare complications and most people get better quickly with just supportive care. Patients can usually return to their normal daily activities after their symptoms improve.
Take Home Message
People should be mindful of chest pain. If somebody develops chest pain, shortness of breath, dizziness, or palpitations days to weeks after the vaccine should seek medical advice from a primary care provider or a cardiologist.
