The muscles in the heart, especially the myocardium, need to contract and relax in a synchronised manner to ensure the steady pumping of blood and its circulation. However, one infection that can affect the proper functioning of the heart is myocarditis which is the inflammation of the myocardium (the heart’s muscles) due to viral, bacterial and fungal infections. Often, viral infections like the common cold and influenza could become severe and trigger inflammation in the heart.
The heart is covered by three layers of muscle. Myocardium is the thick middle layer between the endocardium (inner layer) and the epicardium (outer layer).
Dr Praveen Kahale, cardiology consultant at Kokilaben Dhirubhai Ambani Hospital in Mumbai says that the myocardium has an important function. “This thick layer covers the heart’s walls and enables the heart to contract.”
According to Dr Divya Marina Fernandes, consultant, heart failure specialist and interventional cardiologist at Aster R V Hospital, Bengaluru, an infection can bring down the heart’s pumping capacity which can lead to chest pain, breathlessness, and extreme tiredness.
Myocarditis can either be acute or chronic according to the American Heart Association. The first may be resolved swiftly while the second may last over two weeks. Dr Kahale explains that this condition makes the heart weaker, preventing sufficient blood flow to the rest of the body. This may lead to a stroke or a heart attack.
What causes myocarditis?
According to experts, myocarditis commonly occurs due to viral or fungal infection, drug abuse and sometimes due to autoimmune conditions like rheumatoid arthritis, Church Strauss syndrome or SLE (systemic lupus erythematosus – an autoimmune disease).
Dr Kahale says that there is a high chance of the infection creeping into the lungs and respiratory system. Once the infection sets in, it travels to various parts of the body through the blood.
Myocarditis can either be infective or non-infective. “While infective myocarditis is the most common category, post-pandemic viral infections like covid-19 and coxsackievirus [a group of viruses called enteroviruses in which the common strains are hand, foot and mouth disease and herpangina] have been the common causes of this,” explains Dr Kahale.
Acute and chronic myocarditis
There are two main types of myocarditis – acute and chronic. “Acute myocarditis occurs suddenly and causes complications whereas chronic myocarditis is a long-term process which occurs for over a few months,” Dr Kahale explains.
Some types of non-infective myocarditis are:
- Eosinophilic myocarditis (inflammation caused by a white blood cell called eosinophil, infiltrating the heart muscle)
- Giant cell myocarditis (a rare disease where giant cells – made of inflammatory cells – attack the heart muscle and cause scarring)
- Cardiac sarcoidosis (a rare condition in which the body’s immune response to inflammation leads to scarring in the heart tissue, causing abnormal heart rhythms)
Identifying the symptoms
The condition can be diagnosed with an ECG and an echocardiogram. Sometimes, other indicators such as an increase in cardiac enzymes like troponin can point to myocarditis, Dr Fernandes says.
She explains that a person with this infection experiences symptoms like fever, chest pain, breathlessness, fatigue and even irregular heartbeats. Apart from these, blackouts, dizziness, cardiovascular collapse and cardiac arrest are some of the highly alarming indications of the infection.
Managing the condition
Anyone with myocarditis needs to take certain precautions to prevent their condition from deteriorating:
- Avoid contact with people who have the flu or the common cold
- Maintain high levels of personal hygiene to not contract any diseases
- Limit the intake of salt
- Avoid alcohol and quit tobacco
- Consult the doctor regularly
- Be very cautious while engaging in sports and other physical activities
According to a 2020 article published in the Current Treatment Options in Cardiovascular Medicine, physical exertion is a likely trigger for dangerous arrhythmias and worsens the condition in athletes with myocarditis. For this reason, being cautious while playing sports or abstaining from them altogether is an important aspect of managing the initial stage of the condition.
Medication to manage blood pressure, ventilator support and circulatory support are usually required for people with myocarditis. The duration of recovery usually varies from four to six weeks.