COVID-19 and myocarditis

• COVID-19 myocarditis is an infection of the heart muscle caused by COVID-19.
• In rare cases, COVID-19 vaccination can cause myocarditis as well. 
• It’s vital to get the appropriate care for myocarditis to avoid complications. 

COVID-19 myocarditis can be a possible consequence of an infection with the coronavirus and may lead to serious health problems. In this article, we’ll discuss how COVID-19 can be linked to myocarditis, how myocarditis can be diagnosed, and which treatment options are available. 

COVID-19 myocarditis is an inflammation of the muscular wall of the heart caused by the coronavirus. In some cases, the inflammation can also reach the fibrous sac surrounding the heart muscle called the pericardium. Depending on the structure which is inflamed, the condition gets a different name: 1

• Myocarditis: an inflammation of the heart muscle
• Pericarditis: an inflammation of the fibrous sac surrounding the heart muscle 
• Myopericarditis: an inflammation of both the heart muscle and the fibrous sac surrounding it 

It should be noted that myocarditis may lead to more serious consequences than pericarditis. The most serious consequences are heart failure and dilated cardiomyopathy, which makes it harder for the heart to pump blood around the body. 2

Myocarditis can occur after COVID-19. This happens because the immune system reacts against the coronavirus and causes inflammation. The inflammation can occur in various places of the body, including the heart muscle. The inflammation of the heart muscle can linger on even after the virus has gone. 

Myocarditis is mainly caused by a virus, such as the coronavirus, the flu, or another viral infection. Other possible causes of myocarditis may be: 

• Bacterial or fungal infections
• Autoimmune diseases such as lupus
• A reaction to drugs or harmful toxins 
• A reaction to certain medicines or vaccines.    

Myocarditis can happen as a side-effect of COVID-19 vaccination in rare cases. This occurs most frequently with adolescents and young adult males within a few days after receiving COVID-19 vaccination with Pfizer-BioNTech or Moderna. It’s more common for myocarditis to present itself after the second vaccination dose. 3

Myocarditis as a result of COVID-19 vaccination is usually mild and improves quickly with the appropriate care. Once your symptoms improve, you can resume most of your daily activities. As myocarditis can severely impact your heart muscle, it’s essential to talk to your cardiologist about when you can restart exercising. 2 3

Although myocarditis and COVID-19 vaccination have been linked, the CDC still recommends vaccination for most people 6 months and older. This is because the known risks and potential consequences of COVID-19 infection outweigh the potential risk of developing pericarditis after COVID-19 vaccination. It’s also important to receive all recommended vaccine doses and keep your vaccination current. If you have concerns about COVID-19 vaccination, you should ask your healthcare provider for advice. 3

Not everyone who gets myocarditis from a COVID-19 infection presents the same symptoms. Usually, the symptoms of myocarditis appear around 2 weeks after the symptoms of COVID-19. Some of the symptoms that you may experience are: 2 4

• Chest pain or a tight feeling in the chest
• Shortness of breath
• Fatigue
• Fever 
• A feeling like your heart is fluttering, racing, or pounding
• An irregular heartbeat
• Feeling light-headed or fainting

To diagnose COVID-19 myocarditis, your physician will first ask you several questions and do a physical examination. After that, there are some tests which can help your physician reach a diagnosis, such as: 4

• Blood tests that check for infections
• An electrocardiogram
• An echocardiogram
• A chest X-ray  

These are standard tests that usually do not cause any discomfort or pain. If your doctor suspects that your myocarditis is linked to an active COVID-19 infection, you’ll also need to get tested for COVID-19. The best way to determine whether you have COVID-19 is through a PCR or antigen test. Both require a swab from the back of the throat or the nose, which can then be analyzed. 5 4

COVID-19 myocarditis can be treated by resting, drinking plenty of fluids, and taking painkillers that help alleviate your symptoms. Your healthcare provider can also give you medication to treat the inflammation. In some cases, myocarditis may require hospitalization. 4

If you have myocarditis, then it’s important not to strain the heart muscle with strenuous exercise, as the heart muscle should rest as much as possible. Your doctor will be able to tell you when you can start exercising again, as this is often different for each case of myocarditis. 

In rare cases, myocarditis can cause damage to the heart muscle, which affects its function. To monitor this, your doctor will check your progress closely. Going to your follow-up appointments is crucial, even if you’re feeling better. If you notice that your symptoms return, it’s important to contact your doctor as soon as possible. 

COVID-19 myocarditis is rare and can be resolved with appropriate care. If you start feeling myocarditis symptoms shortly after COVID-19, then it’s vital to contact your doctor for diagnosis and treatment. 

Q: When does myocarditis present after COVID-19? 
A: Usually, myocarditis symptoms first appear around 2 weeks after the symptoms of COVID-19. 

Q: How long does myocarditis last after COVID-19? 
A: COVID-19 myocarditis usually improves within days to weeks. However, it’s crucial to go to the check-ups your physician recommends, as the inflammation caused by myocarditis can cause damage to the heart muscle. 

Q: How does COVID-19 cause myocarditis? 
A: The infection with the coronavirus causes a reaction from the immune system, which consequently causes inflammation. This inflammation can occur in the heart muscle, which is known as myocarditis.