A Centers for Disease Control and Prevention (CDC) advisory panel is set to meet Wednesday to discuss reports of myocarditis and pericarditis in some COVID-19 mRNA vaccine recipients. Leading up to the meeting, the agency’s director, Dr. Rochelle Walensky, stressed that it’s a small fraction of recipients, mostly teens and young adults and that the risk for "mild" myocarditis remains "quite rare," but what exactly is it, and what does it mean for those who do develop it? 

Myocarditis, pericarditis and endocarditis are the three main types of heart inflammation, with the diagnosis of each dependent on the location of the swelling. Myocarditis is inflammation of heart muscle, pericarditis is inflammation of the tissue that forms a sac around the heart and endocarditis is inflammation of the inner lining of the heart’s chambers and valves, according to the National Heart, Lung and Blood Institute. 

While the panel on Wednesday will discuss a potential link to mRNA vaccines, the most common causes of the inflammation include viral or bacterial infections and medical conditions that damage the heart and cause inflammation. It is estimated to impact thousands of adults and children around the world, but signs and symptoms may differ depending on where the inflammation occurs. 

CDC DIRECTOR SAYS BENEFITS OF COVID-19 VACCINATION ‘FAR OUTWEIGH’ RISKS OF RARE HEART ISSUES

For myocarditis specifically, symptoms may include shortness of breath, particularly when lying down or after exercise, fatigue, heart palpitations, chest pain or pressure, lightheadedness, swelling in the hands, legs, ankles and feet or a sudden loss of consciousness, according to the Myocarditis Foundation. 

The majority of cases, however, have no symptoms and are not diagnosed. For those who do seek medical treatment, physicians may order an electrocardiogram, an echocardiogram or a chest X-ray. 

The National Heart, Lung and Blood Institute notes that treatment will also depend on whether a patient is diagnosed with inflammation of the lining of the heart or valves, the heart muscle or the tissue surrounding the heart. Once diagnosed, treatment may involve medicines, a procedure or possibly even surgery to treat the condition and potential complications, which could include arrhythmia, irregular heartbeat or even heart failure. 

Seven cases of myocarditis-like symptoms in patients who had received a COVID-19 vaccine that were reported to the CDC were then detailed in a study published in Circulation. In those seven cases, all patients were males under age 40 who required hospitalization. None of the patients reported heart palpitations and none had signs of heart arrhythmias, a course of treatment varied but included beta-blocker and anti-inflammatory medications. All patients were discharged within two to four days after admission, and all symptoms had resolved before then. 

CLICK HERE FOR COMPLETE CORONAVIRUS COVERAGE

The American Heart Association at this time continues to recommend COVID-19 vaccine for all adults and children ages 12 and older, and notes that fewer than 1,000 cases have been reported amidst a backdrop of nearly 312 million doses of COVID-19 vaccines administered.