What to know about long COVID and myocarditis

This far into the COVID-19 pandemic, you more than likely know someone who has had COVID-19—or maybe you were diagnosed with it yourself. Most mild to moderate cases will take roughly 2 weeks to resolve. However, you probably don't expect symptoms from COVID-19 to last several weeks—or even months.

Long-COVID is when the symptoms of COVID-19 just linger. Some of these symptoms are heart-related, which can include chest pain, shortness of breath, palpitations and dizziness.

The trouble is, it can be tricky to tell if the symptoms are from COVID or if they're from a heart problem like myocarditis (inflammation of the heart muscle).

Your heart muscle is responsible for how your heart contracts when pumping blood. When you have myocarditis, your heart enlarges and gets weaker. The inflammation can also cause scar tissue and make your heart work even harder to pump blood and oxygen around your body.

Charles Wade, MD, a cardiologist with Lankenau Heart Institute, who treated thousands of COVID patients while serving in the U.S. Navy Medical Corps prior to joining Main Line Health in July of 2022, says he's seen long-COVID affect the heart of many of his patients.

Dr. Wade discusses which symptoms and tests may point to myocarditis, how to know if it's COVID-related and other information long-COVID patients should know.

What's the connection between long-COVID and myocarditis?

COVID-19 is primarily a respiratory disease, meaning it affects your lungs. But because it's a virus, it can also damage any of your organs.

When the virus spreads to your heart it can cause many different heart health issues, one of which is myocarditis.

"Myocarditis is a disease that makes the tissue of your heart muscle inflamed," says Dr. Wade.

For some people, the heart problems might not appear until long after they've recovered from COVID. Usually, long-COVID of the heart shows up within the first month of a COVID infection.

What causes COVID myocarditis?

The body's immune system is the suspected culprit for COVID myocarditis.

"We think it's due to the body's own immune system ramping up," says Dr. Wade. "The body sees the COVID, gets fired up and causes a big inflammatory response."

The symptoms—chest pain and palpitations—are caused by the body's own inflammatory response, adding that the heart tissue starts to change.

Other myocarditis symptoms include:

• Fatigue
• Lightheadedness
• Swollen legs, ankles and feet and hands
• Trouble breathing
• Chest pressure
• Sudden loss of consciousness
• Heart palpitations (pounding or fast-beating heart)

Your cardiologist will run tests to diagnose your symptoms before recommending a treatment.

What tests are used to check for heart damage caused by myocarditis?

If you have long-COVID, and the symptoms seem heart related, you'll need to test for myocarditis.

The first test is usually an electrocardiogram, which captures your heart's electrical activity. Your cardiologist will also want to do a blood test for troponin, which is a specific protein that is only released in your heart muscle when it's damaged. If it's positive for troponin, that's a sign that your heart isn't healthy.

If the troponin test is positive, the next diagnostic test is imaging of the heart. That's when ultrasound waves are used (echocardiogram), or magnetic imaging (cardiac MRI).

"The MRI gives you a little more information because it shows the heart muscle tissue (the myocardium) a little better," says Dr. Wade.

How is heart damage treated?

If it is COVID myocarditis, the treatment depends on the patient. The treatment historically has been supportive care, which helps alleviate symptoms.

Sometimes an anti-inflammatory medication and pain reliever are prescribed for myocarditis patients.

Treatment can include medical devices like implantable cardioverter defibrillators (ICD)—in more severe cases—which can help restart the heart from bad heart rhythms.

The majority of patients with myocarditis see their symptoms clear up after a few days or weeks.

Is heart damage caused by COVID permanent?

For some patients with long-COVID of the heart, the inflammation will clear up. It's the heart palpitations and changes in the heartbeat that tend to remain.

"What I've started to see a lot of in my practice, as we get deeper into the pandemic, are people who have residual symptoms related to COVID—things that never go away," says Dr. Wade. "A lot of people post-COVID have higher heart rates, not for a week, but months to years."

Although the inflammation tends to go away for most, Dr. Wade says he looks for a scar on the heart. If there is a scar, he says that means the inflammation has caused permanent damage to the heart.

"When there's no scar, then we know that the inflammation has gone away and the person has essentially recovered," says Dr. Wade.

What to do if you think you have myocarditis from long-COVID?

One way to tell if you've developed a heart problem after COVID is if you feel chest pain that's unrelated to breathing. When this happens, you should seek medical attention. You should also watch for symptoms like fluid retention—you might begin to notice that your legs or stomach start to swell.

"Those are all signs that you want to go to the hospital," says Dr. Wade. "Long-COVID of the heart symptoms generally start during initial infection and are continuous."

If you're someone with pre-existing health conditions like heart disease and diabetes, you're more likely to have myocarditis if you've had COVID. This heart condition, although rare, primarily affects young men.

The good news, though, is that most myocarditis patients survive and live long lives after treatment.

How to keep your heart healthy after COVID

After having COVID, you should slowly resume exercise and other strenuous physical activities.

"You don't want to go out and sprint on the first day," says Dr. Wade. "If you have COVID myocarditis, or inflammation of the heart, then you only want to resume exercise under the supervision of a physician."

If your COVID isn't related to your heart, then during recovery you'll just want to focus on your breathing and not doing too much too soon.

It's important to take steps to keep your heart healthy in general, like eating a well-balanced diet.

"Going to the doctor and doing all of your routine preventative care, and taking care of your chronic conditions can help you to survive COVID if you get it, along with practicing weight management, and eating healthy," says Dr. Wade.

Next steps:

Schedule an appointment with Charles Wade, MD
Treating long-haul COVID patients one unique symptom at a time at Bryn Mawr Rehab
What COVID-19 is doing to your heart