Myocarditis in children

Myocarditis in children is a disease characterized by the defeat of the inflammatory heart muscle caused by the infection, parasitic or protozoal invasion, chemical and physical factors directly or mediated through immune mechanisms, as well as arising from allergic, autoimmune diseases and heart transplantation.

Myocarditis can be an independent disease or a component of various diseases (for example, systemic vasculitis, connective tissue disease, infective endocarditis, etc.). In children, myocarditis is often accompanied by pericarditis (myopericarditis).

ICD10 code

• 101.2. Acute rheumatic myocarditis.
• 109.0. Rheumatic myocarditis.
• 140. Acute myocarditis.
  • 140.0. Infectious myocarditis.
  • 140.1. Isolated myocarditis.
  • 140.8. Other types of acute myocarditis.
  • 140.9. Acute myocarditis, unspecified.
• 141.0. Myocarditis in bacterial diseases classified elsewhere.
• 141.1. Myocarditis in viral diseases classified elsewhere.
• 141.2. Myocarditis in infectious and parasitic diseases classified elsewhere.
• 141.8. Myocarditis in other diseases classified elsewhere.
• 142. Cardiomyopathy.
• 151.4. Myocarditis, unspecified.

198.1. The defeat of the cardiovascular system in other infectious and parasitic diseases classified elsewhere. It should be noted that the International Statistical Classification of Diseases (ICD-10). Adopted in 1995, there is a rubric "acute myocarditis", although the concept of "chronic myocarditis" is absent. Therefore, if the inflammatory disease of the myocardium is not acute (prolonged or chronic), but relatively favorable character, it can be referred to the rubric "myocarditis - 141.1; 141.0; 141; 141.2; 141.8; 151.4. This implies that the disease is secondary. If the inflammation of the cardiac muscle has an unfavorable course, characterized by progressive heart failure, cardiomegaly, it should be classified under the heading "cardiomyopathy".

Epidemiology of myocarditis in children

Given the variety of clinical picture of myocarditis, its frequency in the general population remains unknown. Pathomorphological data indicate that according to the results of 1420 autopsies of children aged 8 days to 16 years, myocarditis was detected in 6.8% of cases, while 4,7% of cases were found at 3,712 autopsies of adults. According to R. Friedman, among sudden-onset children aged 1 to 17 years, myocarditis was diagnosed in 17% of cases. According to the results of pathoanatomical studies presented by Okuni, out of 47 suddenly deceased schoolchildren, 21% had chronic myocarditis. In the period of epidemics, the frequency of myocarditis significantly increases. So, during the epidemic of 1990-1996. With the toxic form of diphtheria, its frequency reached 40-60%, and among the causes of death, myocarditis accounted for 15-60% of cases. Most often in children, myocarditis is found during epidemics caused by the Coxsackie virus, they are characterized by a high mortality rate (up to 50%) in newborns and children of the first years of life.

Recently, there has been an increase in the incidence of myocarditis, which is associated with improved diagnostics, as well as an increase in the number of allergic reactions, changes in the reactivity of the organism, immunization, growth and prevalence of respiratory viral infections, the appearance of previously unknown diseases affecting the myocardium, the evolution of most diseases.

[1], [2]

Causes of myocarditis

The causes of myocarditis in children are diverse. It develops in pathological conditions that are accompanied by hypersensitivity, for example, in acute rheumatic fever, or due to exposure to radiation, chemicals, drugs, physical effects. Myocarditis often accompanies systemic diseases of connective tissue, vasculitis, bronchial asthma. Separately, burn and transplant myocarditis have been identified.

What causes myocarditis in children?

[3], [4], [5], [6], [7], [8]

Symptoms of myocarditis in children

Myocarditis, as an inflammatory disease of the myocardium, in most patients of childhood runs without significant cardiac symptoms, and often asymptomatic, usually benign or subclinical. On the other hand, in the syndrome of sudden infant death as a cause of death on autopsy, acute myocarditis is often diagnosed. It should be noted that children rarely make active complaints, more often parents notice a violation of the state of health of the child.

Symptoms of myocarditis

Diagnosis of myocarditis

All patients with suspected myocarditis should conduct the following studies:

• collection of anamnesis of life, family history, history of the disease;
• physical examination;
• laboratory research;
• instrumental research.

The diagnostic search necessarily includes a thorough analysis of the history of the disease, focusing on the relationship of cardiac symptoms with previous episodes of viral, bacterial infections and vague fever, allergic reactions, and vaccinations. However, it is not uncommon in pediatric practice to encounter cases of myocarditis, where there is no definite binding of heart disease to specific etiological causes.

Diagnosis of myocarditis

[9], [10], [11], [12], [13], [14]

Treatment of myocarditis in children

The management of patients with myocarditis depends on the nature of the course of the disease. Acute viral myocarditis often proceeds favorably and ends with recovery without any treatment. Patients with acute clinically expressed myocarditis are hospitalized.

Chronic myocarditis in 30-50% of children acquires a recurrent course, leading to the progression of chronic heart failure. In this case, it is necessary to conduct a consistent multi-stage complex of treatment and recovery measures first in the hospital, and then in a sanatorium or polyclinic. The stationary stage of treatment of patients with chronic myocarditis is from 6 to 8 weeks and includes non-drug (general measures) and drug treatment, sanation of foci of chronic infection, and initial physical rehabilitation.

The main directions of drug treatment are determined by the main links in the pathogenesis of myocarditis: infectious-caused inflammation, inadequate immune response, death of cardiomyocytes (due to necrosis and progressive dystrophy, myocarditis cardiosclerosis), metabolic disturbance of cardiomyocytes. It should be borne in mind that in children myocarditis often occurs against a background of chronic focal infection, which becomes an unfavorable background (intoxication and sensitization of the body), which contributes to the development and progression of myocarditis.

Treatment of myocarditis

Prognosis for myocarditis in children

Acute myocarditis in children mostly proceeds favorably and end with recovery even without treatment, although cases of lethal outcomes are known.

The appearance of symptoms of severe heart failure in acute myocarditis in children is not considered evidence of an unfavorable outcome or transition to the chronic phase. In most cases, laboratory and instrumental indicators are normalized within a month.

Asymptomatic myocarditis usually ends in complete recovery. However, in some patients, mainly after a long latent period, the development of chronic myocarditis with transformation into dilated cardiomyopathy is possible.