It is hard to find a group not been adversely affected by COVID-19 and all its variants in the last two years. One such group that has seen lingering and sometimes fatal effects of COVID-19 infection is athletes — everyone from professional players and student-athletes to semiprofessional athletes and people who simply enjoy exercising. Discussed here are the impacts on the heart after COVID-19, specifically myocarditis.

How does the virus affect the heart?

When someone contracts a coronavirus infection, the interplay of the virus’s spike protein and angiotensin-converting enzyme (ACE2) are literally the key to infection. ACE2 is present in the cells of the body, in particular the heart, and helps regulate blood pressure, wound healing and inflammation. When ACE2 is dysregulated, inflammation increases and alveoli cell death speeds up. Alveoli are the tiny filaments in the lungs that exchange oxygen and carbon dioxide with blood.

“When COVID-19 attacks that ACE2, which protects the heart, it downregulates that protection. That leads to a whole cycle of inflammatory catecholamine-, adrenaline-driven issues, decrease in oxygen,” said Mostafa O. El-Refai, M.D., interventional cardiologist with Norton Heart & Vascular Institute. “Respiratory issues and stress on the body in general can lead to a multitude of potential cardiac issues such as heart failure, blood clots, dysrhythmia, fast heart rates, slow heart rates.”

Myocarditis in post-COVID-19 patients

Inflammation is a serious condition in any part of the body, but one of the most dangerous places it occurs is the heart. Myocarditis is inflammation of the tissues and lining of the heart. Chronic or untreated myocarditis can lead to a weakening of the heart muscle, inflammation of the pericardium, arrhythmias, stroke, heart attack and, in rare cases, sudden cardiac death.

At the beginning of the worldwide pandemic, research on myocarditis and COVID-19 fueled fears of long-term heart damage, potential death and other serious complications. As time has gone on, however, those fears have been dismantled by data.

“If a patient presents with symptoms, we do need to take those seriously,” Dr. El-Refai said. “Chest pain, shortness of breath, swelling in the legs and heart palpitations are all worth closer investigation.”

Tests may include:

• Blood tests that look for inflammatory markers present in the blood — like C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR), which measures how quickly red blood cells drop to the bottom of a test tube
• Physical tests such as echocardiogram ultrasounds or electrocardiogram (EKG), which evaluate the heart’s electrical output for irregularities

If myocarditis is present and acute, treatments include:

• Steroid therapy uses drugs such as colchicine, or intravenous immunoglobulin (IVIG) or IL-6 inhibitors if someone is very sick.
• In extremely rare cases, extracorporeal membrane oxygenation (ECMO) may be used. This is often referred to as a heart-lung machine.

“Over the long term, if a physician sees someone who actually had a hospitalization and was found to have serious myocarditis, it leads to a very long period of hiatus from sports: three to six months of only low-intensity activity. If you push your heart when it’s inflamed, it just gets more inflamed and then it scars over and then it weakens. So, the heart of myocarditis is rest until you are better,” Dr. El-Refai said. “And how do we know you’re better, repeat echo[cardiogram].

“If your heart muscle was weak at the time that you initially presented with myocarditis, you can’t start doing any type of intense activity unless it gets strong again. Your inflammatory markers should get better, the CRP, ESR. Your markers of heart damage like troponin and BNP [B-type natriuretic peptide] should be better.”

Getting back in the game

“It’s never zero to 60,” Dr. El-Refai said. “We want a gradual return to play after the athlete has been cleared with some of the tests mentioned previously.”

Other tests might include a cardiac MRI. There is no set number of days to wait for returning to play, rather that decision is made based on a combination of test results, symptoms and their severity.

After a very severe bout of myocarditis, those rules shift a little. Returning to the game can come after a series of careful examinations including stress testing, scans and bloodwork.

“The bottom line is that we look at the big picture, and we use the data we can gather to make decisions that have the patient’s health in mind for both now and in the future,” Dr. El-Refai said.