What is heart inflammation?

Pericarditis can be caused by a variety of things. Sometimes the cause of pericarditis isn’t clear, but sometimes it is caused by:

• Viral or bacterial infections. Tuberculosis is one of the most common bacterial causes, but in Australia, the most common cause is a virus.
• Cardiac events. Including myocardial infarction (heart attack).
• Other health conditions. Conditions that can cause pericarditis include chronic kidney failure, systemic autoimmune disease, rheumatoid arthritis and cancers (specifically lung, breast and blood).
• Heart operations or procedures. For example, ablation for atrial fibrillation can cause pericarditis.
• Vaccines. Some vaccines have been shown to increase the risk of pericarditis, although this is rare.
• Idiopathic, is what we call pericarditis when we don’t know what the cause is.

Every person’s body will reach differently to these causes – so if they may cause pericarditis in some people, but not in everyone.

The symptoms you experience can differ depending on the cause of your pericarditis. Pericarditis can be recurrent, which means that it returns after a period of having no symptoms. Symptoms can include:

• Chest pain – is the most common symptom and is often described as a sharp pain behind the breastbone which is worse when lying down and improves when sitting up or leaning forward.
• Fever – can include sweating and chills.
• Heart palpitations – or an irregular heartbeat.
• Aches and pains – often in your neck, shoulders or arms.
• Nausea
• Asymptomatic – sometimes people with pericarditis don’t have any symptoms.
• Swelling in your legs, ankles and feet; shortness of breath; or faintness are symptoms of cardiac tamponade, a serious complication of pericarditis.
• Importantly, a lot of the symptoms of pericarditis are similar to those you might experience with a heart attack. If you have any of these symptoms, it could be a heart attack. Call Triple Zero (000) right away. Remember that every minute counts for someone having a heart attack.

To diagnose pericarditis, your healthcare professional might use:

• Physical examination – listening to your heart with a stethoscope can amplify the sound the layers of the pericardium rubbing together (pericardial rub).
• Electrocardiogram (ECG) – people with pericarditis will have a unique pattern in the electrical signals in their heart which can be seen with an ECG.
• Echocardiogram – this can show your healthcare provider if there is a thickening of your pericardium, or a build-up of fluid (pericardial effusion).
• Chest X-ray – can show the size of your pericardium and also help eliminate other causes for chest pain.
• Blood test – can show markers of inflammation.

The treatment for pericarditis will depend on the cause, but might include:

• Non-steroidal anti-inflammatory medicines – these help to reduce pain and inflammation.
• Colchicine – a different type of medicine to reduce inflammation.
• Corticosteroids – most commonly prednisone, help to reduce inflammation. You may be prescribed these if you have recurrent pericarditis, or your pericarditis is not responding to other medicines.
• Surgery – excess fluid can be removed from the pericardium using a needle (pericardiocentesis) or some of the pericardium can be removed (pericardiectomy).

Most cases of pericarditis are mild and will resolve themselves without requiring treatment. However, in about 5% of cases, the fluid build-up becomes large enough to interfere with your heart’s functioning. This is called cardiac tamponade and is a medical emergency, medical treatment should be sought immediately.

Myocarditis can be caused by a variety of things, including:

• Viral, bacterial or parasitic infections. Viral infections are the most common cause in Australia, including influenza (the ‘flu’), adenovirus (common cold), COVID-19 and gastroenteritis (tummy bug).
• Other health conditions. Conditions that can cause myocarditis include autoimmune disease, and inflammatory bowel disease.
• Drug reactions. This can include both medicines that have been prescribed to you, and recreational drugs like alcohol and cocaine.
• Reactions to other substances. This can include carbon monoxide, spider bites or bee stings.
• Vaccines. Some vaccines have been shown to increase the risk of myocarditis, although this is rare.
• Idiopathic, is what we call myocarditis when we don’t know what the cause is.

Symptoms of myocarditis can include:

• Chest pain – is the most common symptom and is often described as a sharp pain behind the breastbone which is worse when lying down and improves when sitting up or leaning forward.
• Swelling – most often in your legs, ankles and feet.
• Heart palpitations – or an irregular heartbeat.
• Shortness of breath – can be worse when lying down and you might not be able to do exercises or activities you normally find easy.
• Light-headedness – or tiredness, sometimes also loss of consciousness.
• Asymptomatic – sometimes people with myocarditis don’t have any symptoms.

To diagnose myocarditis, your healthcare professional might use:

• Blood tests – can show markers of inflammation.
• Electrocardiogram (ECG) – can show your healthcare provider if there are changes happening in the electric signals in your heart.
• Echocardiogram – this can show your healthcare provider if there is a thickening of your pericardium, or a build-up of fluid (pericardial effusion).
• Magnetic resonance imaging (MRI) – this can show your healthcare provider if there is a thickening of your heart muscle, or any changes to the heart’s shape or size.
• Biopsy – in some cases a biopsy can be used to confirm the diagnosis.

Treatments for myocarditis can include:

• Non-steroidal anti-inflammatory medicines – these help to reduce pain and inflammation.
• Colchicine – a different type of medicine to reduce inflammation.
• Corticosteroids – another different type of anti-inflammatory medicine.
• Heart medicines – such as beta-blockers, can help to limit the amount of work your heart needs to do while it is recovering.
• Ventricular assist devices (VADs) – if damage has occurred to the heart a VAD might be used to help the heart keep pumping blood effectively.

Most cases of myocarditis are mild and will resolve themselves without requiring treatment. However, more serious cases can lead to permanent damage to the heart in the form of cardiomyopathy.

Endocarditis is caused by either:

• Bacterial infections. This is the cause of over 80% of endocarditis cases. These infections can originate in other parts of the body, such as in your gums or urinary tract infections, or infections that are in the heart tissues themselves.
• Fungal infections. These are much less common.

Symptoms of endocarditis can include:

• Fever – can include sweating and chills.
• Pain – in the chest or stomach, and sometimes near the site of the infected device. Also, sometimes joint and back pain.
• Heart murmur – you can’t always feel a heart murmur, but people who can describe it like palpitations or ‘fluttering’ in their chest.
• Cough – and sometimes shortness of breath.
• Fatigue – which includes general tiredness.
• Rashes – or skin discolouration on fingers and toes.

To diagnose endocarditis, your healthcare professional might use:

• Blood cultures – these can show if any, and which, bacteria are present in your body that may be causing endocarditis.
• Echocardiogram – these can show areas in your heart where clumps of bacteria and blood have accumulated (called vegetations).
• Computed tomography (CT) – can also show vegetations, as well as any damage to the heart tissue.
• Single-photon emission computed tomography (SPECT) – this technique combines CT scanning with a label that attaches to white blood cells to make them show up on the scan. This highlights areas of infection in the heart (where white blood cells are moving to fight the infection).

Treatments for endocarditis include:

• Antibiotics – to treat the infection.
• Surgery – can be to remove the infected tissue (e.g. valve or implanted cardiac device) and/or to fix valves that have become damaged.

The prognosis for endocarditis varies significantly depending on the cause of the condition, and the timeliness of treatment. It can leave permanent damage in the heart’s valves, or lead to heart failure.

Endocarditis is a medical emergency, and medical treatment should be sought immediately.

• Buoninfante A, Andeweg A, Genov G, et al. Myocarditis associated with COVID-19 vaccination. npj Vaccines 2024;9:122.
• Cremer PC, Klein AL, Imazio M. Diagnosis, risk stratification, and treatment of pericarditis: a review. JAMA. 2024;332(13):1090–1100.
• Falconer JL, Rajani R, Androshchuk V, et al. Exploring links between oral health and infective endocarditis. Front Oral Health. 2024;5:1426903.
• Mulliken JS, Bainbridge ED. Infective endocarditis. Med Clin North Am. 2025;109(3):667–681.
• Pawsat DE, Lee JY. Inflammatory disorders of the heart: pericarditis, myocarditis, and endocarditis. Emerg Med Clin North Am. 1998;16(3):665–681.
• Sattar Y, Shafiq A, Sharma S, e al. What are the early warning signs of myocarditis during the pathway of care? Expert Rev Cardiovasc Ther. 2024;22(10):553–563. 
• Thilakaratne D, Bista R, Zenker M, et al. Myocarditis: diagnostic modalities and treatment options. Cureus. 2025;17(3):e79949.