Inflammation can affect different parts of the heart. When it only affects the muscle of the heart, it is called myocarditis.
When it also affects the lining around the heart (pericardium), it is called myopericarditis. Myopericarditis is more common in teenagers than young children.
Myocarditis may cause these signs and symptoms:
Chest pain
Shortness of breath
Nausea, which is less common but can happen occasionally
Methods for diagnosing myocarditis can include:
A medical history
Physical exam
Blood samples for laboratory work to test for certain signs (inflammatory markers) of specific infections
Chest x-rays
An MRI of the heart, typically used to make a final diagnosis
Myocarditis usually is caused by a viral infection, including flu viruses, cold viruses, parvoviruses (called fifth disease) and COVID-19. These viral infections cause an immune response that leads to inflammation in the heart. This may be the same reason that mild myocarditis can be a very rare side effect of some COVID-19 vaccines.
Myocarditis can also be caused by:
A bacterial infection, including infections caused by staph bacteria, strep bacteria and the bacterium that causes Lyme disease
Fungi, including one found in bird droppings
Allergic or toxic reaction to a medication, including some antibiotics and illegal drugs
Exposure to radiation or some chemicals, such as carbon monoxide
Some diseases, such as lupus
Occasionally, myocarditis isn’t caused by any of these issues and there is no clear reason why a child has the condition.
Mild myocarditis can get better on its own or with medication. Children may need to rest and avoid sports for three to six months while they recover from the infection that caused the inflammation. It’s important to diagnose and treat myocarditis early. Children with mild myocarditis typically recover completely.
For more severe myocarditis, the heart can take a while to heal. We may use heart medicines like beta blockers or ACE inhibitors. Doctors may also use IVIG (intravenous immune globulin) or steroids. Some children may need to spend time in the ICU and may need help from a mechanical ventilator to temporarily support their heart and lungs.
In the most severe cases, a child may need a heart transplant. The pediatric cardiology care team at Children’s Health can provide complete care, from early diagnosis to the most advanced treatments.