Introduction

Endocarditis is a rare and potentially fatal infection of the inner lining of the heart (the endocardium). It's most commonly caused by bacteria entering the blood and travelling to the heart.

Although the heart is usually well protected against infection,it may be easier for bacteria to bypassthe immune system in people who have:

• aprosthetic (artificial) heart valve valve replacement surgery is increasingly being used when people experience narrowing of one of their heart valves
• Congenital heart where a person is born with heart defects
• hypertrophic cardiomyopathy where the heart muscle cells have enlarged and the walls of the heart chambers thicken
• damaged heart valves because of infection or heart disease

People who inject drugs are also more likely to develop endocarditis.

You'll need to be admitted to hospital for this.

Around one in five people also need surgery to repair or replace a damaged heart valve or drain away any abscesses that develop.

Endocarditis is a serious illness, especially if complications develop. Even with the highest standard of medical care the risk of dying is around one in five. Early diagnosis and treatment is vital to improve the outlook for the condition.

Who's affected?

Endocarditis is a rare condition in England, even in those with a higher risk. It's estimated to affect around one in every 3,000 people every year.

Endocarditis is more common in older people, with half of all cases developing in people aged over 50. However, cases of endocarditis have been recorded in children, particularly those born with congenital heart disease. Twice as many men are affected as women.

Although it may sound strange, rates of endocarditis are increasing because of advances in medical care. This is due to an increasing number of people being treated with valve replacement surgery or surgery to repair congenital heart disease.

Bacteria

Bacteria are tiny, single-celled organisms that live in the body. Some can cause illness and disease and others are good for you.

Brain

The brain controls thought, memory and emotion. It sends messages to the body controlling movement, speech and senses.

Heart valves

Heart valves are four sets of flaps that control the direction that blood pumps around the heart.

Inflammation

Inflammation is the body's response to infection, irritation or injury. It causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Kidneys

Kidneys are a pair of bean-shaped organs located at the back of the abdomen. They remove waste and extra fluid from the blood and pass them out of the body as urine.

Lungs

Lungs are a pair of organs in the chest that control breathing. They remove carbon dioxide from the blood and replace it with oxygen.

Tissue

Body tissue is made up of groups of cells that perform a specific job, such as protecting the body against infection, producing movement or storing fat.