Medical expert of the article
New publications
Viral myocarditis
Last reviewed: 12.07.2025
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Viral myocarditis is a pathological condition of viral genesis with damage to the myocardium (heart muscle). A large number of viruses can cause myocarditis, but it is worth paying attention to infection with Coxsackie viruses A and B, influenza, hepatitis, herpes and ECHO viruses.
Myocarditis of viral origin is most often observed during the flu epidemic. The pathogenesis of the disease is based on the damage of the myocardium by viruses, infection with which occurs 2-3 weeks before the development of myocarditis. The nature of the damage is infectious-allergic, which determines the clinical picture of the disease.
Myocarditis is detected only in some cases, as it sometimes passes without typical manifestations and is masked as a respiratory pathology. Viral myocarditis does not require specific treatment, as it can heal on its own, but changes in the ECG and EchoCG persist for several months.
Causes of viral myocarditis
In most cases, the causes of viral myocarditis are Coxsackie, hepatitis, herpes, rubella, adenoviruses, polio, influenza and ECHO viruses.
The most common causative agent of myocarditis is the Coxsackie virus, which belongs to the group of enteroviruses (RNA-containing). Seasonality is typical for damage to the heart muscle by this virus, in particular, the summer and autumn periods.
In addition, Coxsackie is the cause of acute myopericarditis. The virus has a high tropism for the myocardium. Thanks to modern diagnostic methods, it becomes possible to detect the pathogen in the cells of the myocardium, pericardium and heart valves.
The prevalence of myocardial infarction caused by Coxsackie reaches 50 percent of all cases of viral heart disease. The disease is observed at any age, but the most likely development of myocardial infarction is in young and middle age.
The causes of viral myocarditis in the form of the Coxsackie virus can provoke pathology after 50 years in people suffering from ischemic damage to blood vessels.
Men most often suffer from myocarditis and myopericarditis. In women, most cases of the disease occur during pregnancy and lactation. If myocarditis develops during pregnancy, the likelihood of infection of the fetus increases, which can cause stillbirth. As a result, myocarditis can be observed in newborns during the first six months of life.
[ Symptoms of viral myocarditis
Clinical symptoms of viral myocarditis caused by the Coxsackie B virus are characterized by an increase in body temperature, signs of inflammation of the gastric and intestinal mucosa, such as moderate pain in the epigastric region, nausea, vomiting, and intestinal dysfunction in the form of diarrhea.
When myocarditis symptoms are added, there are interruptions in the heart's work, pain and a feeling of lack of air. However, in most cases, pleurodynia (pain syndrome when moving the chest, which occurs as a result of damage to the pleural sheets) is added.
As the pathology progresses, the spleen may increase in size, lymphadenopathy and orchitis may develop. At the age of up to 20 years, an acute onset and the addition of pleurisy or pericarditis is observed, but, characteristically, the disease ends quickly and with complete recovery. At the age of over 40 years, the pathology has a more gradual onset with a predominance of cardiac symptoms (pain, shortness of breath, palpitations), which is sometimes mistaken for angina due to coronary heart disease.
Symptoms of viral myocarditis may also include signs of upper respiratory tract dysfunction, heart failure, pain in the muscles, joints and chest.
If the cause of myocarditis is the flu virus, which usually occurs during an epidemic, then the signs of myocarditis develop within a week or two after infection. The flu virus A affects the myocardium in 9.7% of all cases, and flu B – 6.6%.
Symptoms in this case include tachycardia, irregular heartbeat, pain, shortness of breath, and signs of heart failure. In most cases, the pericardium is affected.
Myocarditis can develop as a result of infection with the polio virus. Due to the fact that the pathology is a severe disease, myocarditis can be registered after death. Myocardial damage is focal with clinical signs of cardiac, vascular and respiratory failure, which are observed against the background of bulbar paralysis.
In addition, there is a possibility of myocarditis in the presence of viral hepatitis. In this case, symptoms of damage to the heart muscle are noted for a week to 3 weeks.
Viral myocarditis in children
Acute myocardial damage is more common in children. The most severe course is in newborns and younger children. Statistics show that boys suffer from myocarditis more often than girls.
The main factor in the development of severe myocarditis is considered to be an insufficient level of immunity, which can be caused by frequent respiratory diseases, concomitant diseases, including chronic ones, excessive physical and psycho-emotional stress, as well as poor nutrition, daily routine and insufficient sleep.
In addition, viral myocarditis in children can be severe if there is a genetic predisposition in the form of an inadequate immune response to the virus.
It is customary to distinguish acute myocarditis - up to 1.5 months, subacute - up to 2.5 years and chronic. In addition, babies can suffer from mild, moderate and severe myocarditis.
Symptoms of heart muscle damage are observed against the background of infection of the body with some virus. At first, the general condition of the baby worsens, hyperthermia increases, the skin turns pale, lethargy and decreased motor activity appear.
In infancy, the baby sucks the breast weakly or refuses it altogether. In older age, children complain of pain in the whole body (joints, muscles, abdomen, heart), a feeling of lack of air (shortness of breath) and interruptions in the work of the heart.
If viral myocarditis is detected in children, then an objective examination by a doctor reveals an increase in the size of the heart. When listening to the work, an irregular heart rhythm is noted (extrasystoles appear - an unscheduled contraction), the pulse is rapid.
In addition, a systolic murmur may be heard, which is clearly audible at the apex. It is associated with insufficiency of the mitral valve, located between the left atrium and ventricle of the heart.
In severe myocardial damage, heart failure is observed, which is more common in infancy. In most cases, myocarditis ends in recovery, but in some cases, persistent rhythm disturbances are possible due to the development of cardiosclerosis.
Where does it hurt?
Diagnosis of viral myocarditis
In order to make a correct diagnosis, it is necessary to know all the details of the onset of the disease, as well as find a connection with a previous viral pathology.
Diagnosis of viral myocarditis with suspected Coxsackie virus consists of the presence of typical clinical features of gastroenteritis before the appearance of cardiac symptoms, as well as confirmation by laboratory diagnostic methods.
They consist of studying paired sera, where it is necessary to detect a fourfold increase in the antibody titer in the blood, detecting the virus or its antigen in feces using electron microscopy, as well as in other biological fluids.
In addition, immunoelectroosmophoresis, detection of Coxsackie RNA in the blood and in the myocardium using biopsy and the PCR method are widely used.
An ECG examination reveals pathological Q, ST and T changes on the cardiogram. Ventricular extrasystoles and AV conduction disturbances are quite common. It is also worth highlighting the appearance of persistent diffuse changes in the work of the left ventricle.
The diagnosis of viral myocarditis in influenza is based on an ECG study, when the cardiogram, in addition to periodic changes in T and ST, reveals increased heart rate, rhythm and conduction disturbances with the appearance of AV blocks.
The cardiogram for myocarditis caused by the poliomyelitis pathogen is characterized by non-specific changes - an increase in PR, QT, the appearance of extrasystoles, tachycardia up to atrial fibrillation.
In addition to instrumental diagnostic methods, a clinical blood test is used to identify the inflammatory process in the body and the heart muscle in particular. General indicators such as accelerated ESR, increased levels of leukocytes and neutrophils indicate the presence of an inflammatory focus in the body. An increase in sarcoplasmic enzymes - LDH and CPK - indicates myocardial damage.
What do need to examine?
How to examine?
Who to contact?
Treatment of viral myocarditis
Regardless of the cause of the heart muscle damage, the treatment of viral myocarditis is largely symptomatic. However, in each case, therapy should be selected individually, taking into account the severity of the pathology and concomitant diseases.
In the presence of the Coxsackie virus, it is necessary to avoid the use of drugs that have a direct effect on the blood coagulation system, such as anticoagulants. Of course, there is a high probability of intracardiac thrombus formation, but in this case it is necessary to prevent cardiac tamponade. It can be caused by the appearance of hemorrhagic exudate in the pericardial cavity.
Treatment of viral myocarditis in influenza type A is based on the use of rimantadine, which should be taken for a week, starting no later than 2 days after the first symptoms of influenza infection. There are suggestions that ribavirin is effective in cases of infection with the B virus, but this has no evidence base.
In poliomyelitis, respiratory function must be monitored. Given that the pathogenesis involves the development of bulbar paralysis, further damage to the respiratory and vascular center is possible, which threatens the patient's life.
Prevention of viral myocarditis
In some cases, damage to the heart muscle occurs without clinical symptoms, but typical cardiac manifestations are more often observed.
Prevention of viral myocarditis involves timely immunization of the population against viruses such as polio, influenza and other pathogens.
However, vaccination does not provide 100% protection against infection. During an epidemic, it is necessary to use personal protective equipment and avoid contact with infected people who have clinical symptoms of the disease.
Non-specific prevention of viral myocarditis consists of increasing the body's immune defense through walks in the fresh air, hardening, sports, taking vitamins, a healthy balanced diet, and sufficient sleep.
In addition, one should not be exposed to stressful situations and control the activity of chronic pathology. By increasing immunity, the body becomes more resistant to viral pathogens, which reduces the risk of developing viral myocarditis.
If infection does occur, it is necessary to begin pathogenetic treatment in a timely manner to avoid prolonged circulation of the pathogen through the bloodstream and damage to the heart muscle.
Prognosis of viral myocarditis
Most often, myocarditis ends in recovery, but there are cases when persistent changes remain on the cardiogram. The disease lasts for several weeks, but if serious complications develop, such as dilated cardiomyopathy, the risk of death increases.
The prognosis for viral myocarditis when infected with the Coxsackie virus is quite favorable, but it sometimes takes several months to restore the normal picture of the cardiogram. In the absence of full treatment, changes in the ECG can be persistent, which threatens a person's life.
In the presence of the influenza B virus in the body, myocarditis with severe consequences is observed. Among them, it is necessary to focus on hemorrhagic syndrome with hemorrhage into the lung tissue and the development of edema, thromboembolic complications, as a result of which a fatal outcome is possible.
To avoid the occurrence of serious conditions, it is necessary to use preventive methods and consult a doctor in a timely manner. As for damage to the heart muscle in the presence of viral hepatitis, it is necessary to remember that there is a high risk of developing congestive heart failure. As a result, a fatal outcome is possible.
Viral myocarditis affects people of all ages, but without adequate treatment it can have serious complications that threaten life. To avoid this, it is recommended to promptly consult a doctor if you have an infectious disease, as well as periodically examine the heart using ECG and EchoCG, which will allow you to identify pathology at an early stage.