What is myocarditis

Myocarditis is actually a very common disease in life. But if we have not come into contact with patients with myocarditis, it is difficult to know the impact of this disease on us. So, what is myocarditis? To put it simply, there are some inflammatory lesions in our myocardium, which lead to symptoms such as arrhythmia. In fact, there are already very complete treatment options for myocarditis.

Myocarditis refers to a disease characterized by localized or diffuse inflammatory lesions of the myocardium. According to the established Dallas criteria, the histological evidence of myocardial infiltration is myocardial inflammatory cell infiltration accompanied by degeneration and necrosis of adjacent myocardial cells. In 1991, Lieberman divided myocarditis into fulminant myocarditis, acute myocarditis, chronic active myocarditis and chronic persistent myocarditis based on the histological changes and clinical manifestations of myocardial biopsy. The clinical manifestations of myocarditis are diverse, ranging from no symptoms to severe arrhythmias, acute heart failure, cardiogenic shock and even death. Endomyocardial biopsy is the "gold standard" for the diagnosis of myocarditis. The treatment of myocarditis is mainly symptomatic and supportive, mainly for active treatment of shock, heart failure, arrhythmia and other comprehensive treatments, especially for the treatment of patients with fulminant myocarditis.

Myocarditis is often caused by common viral infection or immune response after viral infection. The causes include infectious and non-infectious. Infectious agents include bacteria, fungi, protozoa, parasites, spirochetes, rickettsiae, and viruses. Non-infectious factors include the following: (1) immune-mediated diseases (allergens, alloantigens, autoantigens); (2) toxicity (drugs, heavy metals, biological toxic substances, physical damage, etc.). The most common cause is viral infection, and other factors are less common.

The clinical manifestations of myocarditis vary, mainly depending on the extent and severity of the lesions. A few cases may be completely asymptomatic. Mild cases may present with non-specific symptoms such as fever, cough, and diarrhea. Severe cases may present with serious arrhythmias, heart failure, cardiogenic shock, and even death. Therefore, the possibility of diagnosing myocarditis based on clinical symptoms alone is low. According to the clinical manifestations, myocarditis is divided into mild, subclinical, latent progressive, acute dilated cardiomyopathy, atrioventricular block, myocardial infarction-like and sudden death types.