In medicine (cardiology), myocarditis is inflammation of heart muscle (myocardium). It resembles a heart attack but coronary arteries are not blocked.
Myocarditis is most often due to infection by common viruses, such as parvovirus B19, less commonly non-viral pathogens such as Borrelia burgdorferi (Lyme disease) or Trypanosoma cruzi, or as a hypersensitivity response to drugs.
The consequences of myocarditis thus also vary widely. It can cause a mild disease without any symptoms that resolves itself, or it may cause chest pain, heart failure, or sudden death. An acute myocardial infarction-like syndrome with normal coronary arteries has a good prognosis. Heart failure, even with dilated left ventricle, may have a good prognosis. Ventricular arrhythmias and high-degree heart block have a poor prognosis. Loss of right ventricular function is a strong predictor of death.
Let's talk about singns and symptoms
The signs and symptoms associated with myocarditis are varied, and relate either to the actual inflammation of the myocardium, or the weakness of the heart muscle that is secondary to the inflammation. Signs and symptoms of myocarditis include:
- Chest pain (often described as "stabbing" in character)
- Congestive heart failure (leading to edema, breathlessness and hepatic congestion)
- Palpitations (due to arrhythmias)
- Sudden death (in young adults, myocarditis causes up to 20% of all cases of sudden death)
- Fever (especially when infectious, e.g. in rheumatic fever)
