New guidelines for infective endocarditis prophylaxis

Therapeutic Guidelines has revised the guidelines for the use of antibiotics for prophylaxis against infective endocarditis (seewww.tg.org.au/Prevention_of_endocarditis_update). The major change is that antibiotic prophylaxis is no longer indicated in patients with aortic stenosis, mitral stenosis, or symptomatic or asymptomatic mitral valve prolapse.

The justifications and reasoning behind these changes have been reviewed in the Australian Dental Journal.¹These new guidelines take into consideration the guidelines of the American College of Cardiology/American Heart Association, as well as the British Society for Antimicrobial Chemotherapy and the UK National Institute for Health and Clinical Excellence. The most recent UK guidelines do not recommend antibiotic prophylaxis for any cardiac risk group. Prophylaxis is also not indicated in adolescents and young adults with heart valve disease, apart from indigenous Australians.

The Australian infective endocarditis prophylaxis guidelines differ from the American and UK guidelines in two specific ways:

• The consensus was that, as there is a high incidence of rheumatic heart disease among indigenous Australians and the outcomes of this disease in this population are considered to be significant, indigenous Australians with rheumatic heart disease require prophylaxis.
• Very clear guidelines are given for dental procedures that always require antibiotic prophylaxis for patients with specific cardiac conditions. Further, these guidelines clearly outline dental procedures for which, irrespective of the patient in question, prophylaxis is never required. Finally, dental procedures are outlined where antibiotic prophylaxis should be considered if multiple procedures are being undertaken or the procedure is expected to be prolonged.

Doctors and dentists need to be prepared to discuss the updated guidelines as these changes are bound to concern patients who previously received prophylaxis. The changes may be more of a slow evolution as both patients and clinicians come to appreciate the lack of evidence for a benefit of antibiotic prophylaxis.