Endocarditis

What causes endocarditis?

Endocarditis happens when bacteria or fungi enter your bloodstream, attaching to already damaged areas of your heart.

For example, bacteria can often enter the bloodstream through the mouth or skin because of an existing infection in those areas.

Since there are many ways you may develop endocarditis, your doctor might not be able to find the exact cause. However, those most at risk of endocarditis usually have damaged heart valves, artificial heart valves or other heart defects.

Your risk of endocarditis is higher if you:

• have heart valve disease 
• have had a heart valve replacement using an artificial valve
• have had endocarditis before
• have certain types of congenital heart disease
• have a condition called hypertrophic cardiomyopathy
• inject drugs into your veins.

What are the symptoms of endocarditis?

The symptoms of endocarditis can be hard to notice and unclear, developing slowly over weeks or sometimes months. In some cases, however, they can develop suddenly. 

The most common symptoms of endocarditis are:

• flu-like symptoms – these include having a temperature, tiredness, headaches, chills, a cough and sore throat
• poor appetite or unexplained weight loss
• pale skin
• aching muscles and joints
• heart murmurs (an abnormal heart sound). 

Other rarer symptoms you may see or feel include:

• small dark-coloured spots on the skin
• unusual dark lines under your fingernails
• red lumps on the fingers or toes that might be painful.

If you’ve been told you’re at high risk of developing endocarditis and you have flu-like symptoms with a high temperature for more than a week, see your GP immediately.

When to get help

Infective endocarditis can be fatal if left untreated. Therefore, early detection and prompt management are critically important.

You should contact your healthcare provider as soon as possible if you recognise the above symptoms. This is especially important if you’re at higher risk of developing endocarditis, such as having a history of heart valve disease.

How is endocarditis diagnosed?

In the early stages, the infection often looks similar to other illnesses, which can make it hard to diagnose.

The following procedures can help to diagnose endocarditis:

• blood tests to find out what type of bacteria is causing the inflammation
• an echocardiogram (echo) to look for signs of damage in your heart
• an electrocardiogram (ECG) to look for an abnormal heart rhythm
• a chest X-ray to check for fluid build-up in your lungs
• an MRI scan to get clearer views of your heart.

Because endocarditis is a serious infection, doctors might decide to start treatment while they take steps to confirm the diagnosis.

How is endocarditis treated?

In the early stages of infection, you’ll usually need to be admitted to hospital. You’ll be given antibiotics into your vein through a drip. If your symptoms and temperature improve, your doctor might decide to let you go home.
 
To treat the endocarditis after this stage, you will need to:

• continue taking antibiotics – normally for up to six weeks
• have regular appointments with your GP to monitor your progress
• have blood tests to make sure your body is fighting the infection.

In some cases, you may also end up needing surgery to repair any damage caused to your heart, or to drain away collections of pus called abscesses. 

What are the possible complications of endocarditis?

Sometimes, endocarditis can cause damage to your heart which can lead to heart failure. To work out if this might happen, you’ll need to be under the care of a cardiologist so you can be assessed and monitored regularly. Endocarditis can also increase the risk of stroke.

How can you reduce your risk of endocarditis?

You can lower your risk of developing endocarditis by:

• practicing good oral and dental hygiene
• visiting your dentist regularly
• avoiding body piercing or tattooing
• washing your hands regularly and properly to help stop bacteria spreading
• being aware of the symptoms and contacting your doctor if you’re worried.

Should you take antibiotics to prevent endocarditis?

If you’re at risk of endocarditis, you might be wondering whether you sometimes need to take antibiotics as a precaution.

While people at high risk don’t need antibiotics routinely, occasionally they might be prescribed as a safety measure. For instance, when a medical procedure is taking place in your body where there’s a suspected infection that could spread to your heart.

Overuse of antibiotics can increase the chances of the bacteria becoming resistant to them, so they’re only used when necessary. If you’re concerned about this, talk through the risks and benefits of taking antibiotics with your healthcare provider.

Heart Helpline and other support

• Get in touch with our expert cardiac nurses through our Heart Helpline, which is open Monday to Friday, 9am to 5pm.
• Read Tom’s story of developing endocarditis after an aortic valve replacement.
• Read Stuart’s story of adapting to a new normal after he unexpectedly developed endocarditis.
• Utilise The Improving Access to Psychological Therapies (IAPT) services across the country.
• Speak to others with heart conditions by joining a support group or online community.
• Sign up to our Heart Matters magazine and online information packed with health and lifestyle advice.