What is infective endocarditis?
Infective endocarditis is a rare condition where the inner lining of the heart – most commonly one of the heart valves – becomes infected. It affects about 1,500 people a year in the UK. Most of these people already have some form of abnormality in the structure of the heart.
Infective endocarditis is a serious condition, which can be life-threatening if it’s not treated quickly. Nowadays, if the condition is diagnosed early, most people recover well with antibiotic treatment, although the infection may cause some damage to the heart valves. If this happens, you may need to have surgery to repair or replace the valve.
Who is most at risk of developing endocarditis?
The people who are most at risk of endocarditis are those who have:
· a leaking or stiff heart valve
· a heart valve replacement
· hypertrophic cardiomyopathy
· most types of congenital heart disease – including conditions where the
heart disease has been treated or repaired with surgery (but
there some exceptions to this – see People who are not at risk, below).
· Intravenous drug users are also at risk.
· People who have already had infective endocarditis have a greater risk
of getting it again.
People who are not at risk
People with particular types of congenital heart disease – atrial septal defect (on its own), repaired ventricular septal defect and repaired patent ductus arteriosus – are not at risk of getting endocarditis.
People who have a pacemaker or ICD (internal cardioverter defibrillator), or who have had bypass surgery or a stent to treat angina are not at an increased risk of developing endocarditis.
Endocarditis in people who have entirely normal hearts is extremely rare.
What causes infective endocarditis?
It is caused by a bacterium – or, in some rare cases, another type of infective organism that is in the bloodstream – and which settles onto the abnormal structure or defect in the heart. Although it is not possible to prevent all bacteria from getting into the bloodstream, there are some things you can do to reduce the risk of getting endocarditis:
• Maintain good oral hygiene (teeth and gums) and have regular check-ups
with your dentist.
• Avoid body piercing or tattooing.
• Don’t inject recreational drugs.
Advice for people who are at risk of endocarditis
Up until very recently, people at risk of endocarditis were advised to take antibiotics before having dental treatment and some other forms of treatment. The National Institute for Health and Clinical Excellence (NICE) is the organisation that provides advice on promoting good health and preventing and treating illnesses. It recently looked at all the latest relevant research and concluded that it is very unlikely that there is any overall benefit from taking antibiotics before having dental treatment or certain other procedures. In other words, taking antibiotics before having dental treatment or other tests will not reduce your risk of developing endocarditis. Bacterial resistance to antibiotics is also increasing, making them less effective.
What are the symptoms of infective endocarditis?
One of the reasons why infective endocarditis is so dangerous is that the early symptoms are often very subtle and non-specific. If you are at high risk of getting endocarditis and you have flu-like symptoms with a high temperature that lasts for longer than a week, you should see your GP. Make sure that your GP knows that you are at increased risk of getting endocarditis.
If you know that you are at increased risk of developing infective endocarditis, you should carry an endocarditis warning card to show to your GP and to any other health professionals who may need to give you treatment. You can get one from the British Heart Foundation by calling either the Heart HelpLine on 0300 330 3311 (local rate number) or our Orderline on 0870 600 6566. Please note that these cards are currently being updated in line with the new advice and will be available late 2008.
How is it diagnosed?
Infective endocarditis is diagnosed by looking for clinical signs of the disease – such as a high temperature, or a new or changing heart murmur – and taking blood tests, called blood cultures, to find out if there are bacteria in the bloodstream. Echocardiograms are useful, both to help to confirm a diagnosis, and to assess the heart as treatment progresses.
What is the treatment for infective endocarditis?
If you develop infective endocarditis, you will need to go into hospital to have intravenous antibiotics (antibiotics given through a vein). How long you have to stay in hospital for this treatment will depend on how severe your infection is and on the type of antibiotics needed to treat the infection. You will then need to take antibiotic tablets at home for a further four to six weeks.
If the infection does not respond well to the antibiotics, or if a valve becomes badly damaged as a result of the infection, you may need to have surgery.
For more information
Visit the National Institute for Health and Clinical Excellence (NICE) website: www.nice.org.uk Reference CG64
March 2008