The heart muscle can sometimes be affected by inflammation. An inflamed heart muscle is called myocarditis. Here we talk about this condition in a little more detail.
What is myocarditis?
The word ‘myo’ means muscle and ‘carditis’ means ‘inflammation of the heart’. In simple terms, it means inflammation of the heart muscle.
The heart muscle is made of 3 layers – the outer epicardium, the middle myocardium and the inner endocardium.
Inflammation of this middle layer is called myocarditis.
The condition can cause a variety of different symptoms that we have discussed later. An early diagnosis and treatment can ensure a good recovery. If left untreated, the heart muscle can become weak.
What are the causes of myocarditis?
There are many causes, but it is often difficult to pin point the cause. Some of the common causes include –
1. Viral infections – The virus that causes the common cold (adenovirus) is a common cause. Other viruses that cause gastrointestinal infections and german measles can sometimes cause it. The HIV virus (that causes AIDS) is also a recognised cause. There have been cases where the swine flu virus has caused myocarditis.
2. Bacterial infections – Infections caused by streptococcus and staphylococcus (types of bacteria) can cause myocarditis.
3. Fungal infections – This is a rare cause, and organisms such as candida have been implicated.
4. Parasitic infections – This is a rare cause in India, and can be due to the parasites called trypanosoma and toxoplasma (spread by insects).
5. Drugs – Certain drugs such as penicillin can cause an allergic reaction leading to the development of myocarditis.
6. Other rare causes include conditions such as lupus and Wegener’s granulomatosis.
Below are the common symptoms patients may experience –
- Breathing difficulty when at rest and during physical activity
- Chest pain
- Rapid heart beat (which can sometimes be irregular)
- Body ache
Not all these symptoms occur at once. However, if you do experience them, make sure you see your doctor as soon as possible.
On clinical examination, there may be fluid on the lungs and the heart beat may be high. A low blood pressure may be noted.
Diagnosis of myocarditis
If a clinical diagnosis of myocarditis is made, then your doctor will arrange a few tests that will not only help confirm the diagnosis, but also help determine if the heart muscle has been damaged. Below are certain tests that may be conducted.
1. Blood tests – Specific blood tests that detect any damage to the heart muscle may be performed. These include a troponin and creatine kinase level, along with a white blood cell count and hemoglobin. Other tests looking for rare conditions may be performed if needed.
2. ECG – An ECG can help determine if there is a fault with the conduction of electricity in the heart muscle. Any irregular rhythms can be detected as well.
If the ECG is normal and the doctor suspects you may have an abnormal rhythm, then a holter recording may be performed.
3. Chest X-ray – This test can detect the presence of fluid on the lung and the size of the heart.
4. Echocardiogram – This is an invaluable test in determining the function of the heart muscle. It also helps examine the structure of the heart valves and if there are any problems with the way the heart muscle contracts and relaxes.
5. MRI scan – An MRI scan can study the structure of the heart muscle in great detail. Inflammation of the heart muscle can be seen very clearly in this study.
6. Endomyocardial biopsy – This is a specialised test where a catheter (small tube) is placed into the heart and a piece of heart tissue is removed. This is sent to a pathologist to be examined under a microscope. Specific changes can be seen that can help confirm the diagnosis.