Myocarditis is the inflammation of a heart muscle. This muscle is called the myocardium, and its function is the give mobility to the heart. It contracts to send blood around the body and then relaxes until the heart starts to fill up again.
If the myocardium becomes inflamed, the pumping function is no longer as effective and damage occurs in the cells. Naturally, this is a significant health risk.
It is unsure exactly what percentage of people are affected by this disease. This is because myocarditis does not cause symptoms in many cases.
However, it can occur at any age, even in children.
What is the cause of myocarditis?
In at least 50% of cases, the origin of myocarditis is an infection that comes from viruses, fungi, parasites or bacteria. Frequently, it appears after diarrhea, the cold or the flu.
Other common causes of myocarditis include:
- Allergic reaction to medicines,
- Exposure to certain environmental elements, such as heavy metals,
- Autoimmune processes that cause inflammation.
In addition, some diseases such as rheumatoid arthritis, rheumatic fever and lupus are also associated with myocarditis. Sometimes, it’s impossible to determine the exact cause of the disease.
The processes of myocarditis
The body reacts to the inflammation of the heart muscle by activating the immune system. This sends antibodies to combat the agent that causes inflammation. However, the chemicals produced by those cells can damage the myocardium.
If many cells are damaged, the result is a weakened and inflamed heart. When this process occurs very quickly, heart failure and sudden death may occur.
However, the most common effect is that the heart regenerates by itself. It does this by replacing damaged or dead myocardial cells, leaving scar tissue. This tissue is rigid and therefore does not contribute to the pumping of the heart.
When scar tissue is very extensive, it could cause congestive heart failure or a dilated cardiomyopathy.
Symptoms of the disease
Symptoms of myocarditis are highly variable. In fact, in some cases the disease shows no symptoms.
Either way, it is important to remember that there is both acute myocarditis and chronic myocarditis. Each has its own symptoms.
Acute myocarditis has symptoms similar to heart failure. The most important are:
- Strong and sharp chest pain behind the sternum,
- A bluish discoloration of the skin and mucous membranes, or paleness,
- Shortness of breath,
- Inflammation of the liver and spleen,
- Accumulation of fluid in the legs.
Symptoms of chronic myocarditis are less obvious. In general, sufferers experience a feeling of weakness and decay, fatigue and shortness of breath with minimal effort, changes in appetite, pain in the limbs and weight loss.
Diagnosis and treatment
The diagnosis of myocarditis is problematic, since the symptoms are not very specific and therefore are easily mistaken for other diseases.
Usually, the first thing doctors do is a clinical examination which aims to verify the presence of symptoms and collect information about any recent infections.
If there is suspicion, they may order a chest x-ray to determine whether there is fluid in the lungs. However, the most common procedure is to order an electrocardiogram or an echocardiogram. These allow a detailed examination of the functioning of the heart.
The most accurate method is the endomyocardial biopsy. The results are conclusive, since this test directly shows whether or not the myocardium is inflamed. This test is usually ordered when chronic myocarditis is suspected.
Acute myocarditis goes away by itself in the majority of cases. It recovers by itself, without leaving after-effects. Sometimes, it is complicated and can lead to more serious problems or death. In other cases, it leads to permanent heart failure. It all depends on the state of health of the patient and the factors that caused the disease.