Affecting several thousand Americans each year, myocarditis is a disease marked by inflammation of the heart muscle (myocardium). The real numbers are hard to know because myocarditis often produces no symptoms.
A wide range of infections and other problems can lead to myocarditis, which often develops in people who are otherwise healthy. Prevention or prompt treatment of infections is one of the best ways to prevent myocarditis.
It’s dramatic when someone has a heart attack on television or in the movies. But in real life, symptoms can be more subtle and difficult to identify. And because heart attack and angina symptoms are so similar, it may be hard to tell what's going on.
But knowing the differences -- and the reasons behind them -- can result in seeking treatment sooner, and living longer.
Viral infection is the most common cause of myocarditis.
When you have an infection, your body produces cells to fight infection. These cells also release chemicals. If the disease-fighting cells enter your heart, they can release chemicals that can damage your heart muscle. Your heart may become thick, swollen, and weak. Seeking immediate medical care for infections can help prevent complications.
These are some of the types of infections that can cause myocarditis.
Fungal and parasitic infections can also cause myocarditis.
Other causes of myocarditis include certain chemicals or allergic reactions to medications or toxins such as alcohol, drugs, lead, spider bites, wasp stings, or snakebites and chemotherapy and radiation therapy. Having an autoimmune disease such as lupus or rheumatoid arthritis that causes inflammation throughout your body may also lead to myocarditis.
Signs and Symptoms of Myocarditis
Myocarditis often has no symptoms. In fact, most people recover and never even know they had it.
If you do have symptoms, they may include one or more of these:
Shortness of breath during exercise at first, then at night while lying down
Abnormal heartbeat, which causes fainting in rare cases
An often sharp or stabbing chest pain or pressure, which may spread to neck and shoulders