Myocarditis Symptoms, Causes and Complications

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Myocarditis is a condition in which the heart muscle is inflamed. The myocardium is the heart wall’s middle layer. If this condition is severe, the body may not get enough blood due to the heart’s pumping action being weakened. This can result in a number of life-threatening complications. Myocarditis symptoms will vary depending on severity.


This condition is typically caused by fungal, bacterial, or viral infections that make their way to the heart. Viral infections include:

  • Coxsackie
  • Hepatitis C
  • HIV
  • Cytomegalovirus
  • Herpes
  • Parvovirus

Fungal infections include:

  • Aspergillus
  • Coccidioides
  • Histoplasma
  • Candida
  • Cryptococcus
  • Schistosomiasis

Bacterial infections include:

  • Chlamydia
  • Streptococcus
  • Mycoplasma
  • Treponema

Other possible causes include:

  • Certain parasites
  • Allergic reactions to toxins or medications, such as cocaine, heavy metals, alcohol, certain chemotherapy drugs, and catecholamines
  • Certain conditions causing body-wide inflammation, such as sarcoidosis or rheumatoid arthritis
  • Exposure to certain chemicals


Myocarditis symptoms vary depending on the severity and cause of this condition. Mild cases may not present with noticeable symptoms. Common symptoms include:

  • Chest pain
  • Shortness of breath, during activity or when resting
  • Fatigue
  • Abnormal or rapid heartbeat
  • Fluid retention resulting in swelling of the feet, ankles, and legs
  • Fainting
  • Low urine output
  • Sign of viral infection, such as body aches, fever, diarrhea, headache, joint pain, or sore throat

Children may experience:

  • Fever
  • Breathing difficulties
  • Grayish or bluish skin discoloration
  • Fainting
  • Rapid breathing


In addition to symptoms, complications may also occur. Complications are most common when this condition is severe due to the heart muscle becoming permanently damaged. This damage may result in:

  • Heart failure: Also referred to as congestive heart failure, this conditions occurs when the hearts' ability to transport blood throughout the body is compromised
  • Heart attack: This condition occurs when the heart does not get enough oxygen due to a blood vessel being blocked, resulting in heart muscle death or permanent damage
  • Irregular heartbeats: Also referred to as arrhythmia, this occurs when the heart is either beating too fast or too slow
  • Blood clots: A blood clot is a clump of blood resulting from blood hardening and becoming solid instead of liquid
  • Stroke: A stroke occurs when any part of the brain is disrupted from blood flow
  • Pericarditis: This s a condition in which the pericardium becomes inflamed
  • Cardiomyopathy: This is a condition that occurs when the heart muscle becomes weakened, or heart muscle structure changes, often due to heart function problems or inadequate heart pumping
  • Sudden death: Also referred to as sudden cardiac death, this condition occurs when heart function stops abruptly


The patient’s overall health and the underlying cause will ultimately determine their prognosis. Prognosis varies widely. Some patients may have permanent heart failure, while other patients recover completely.

Resources (2010). Myocarditis. Retrieved on September 14, 2010 from

MedlinePlus. (2010). Myocarditis. Retrieved on September 14, 2010 from MedlinePlus: