Infective endocarditis (IE) is an uncommon disorder that carries a significant morbidity and mortality. Despite advances in diagnostic techniques as well as antimicrobial and surgical treatment, escalating antibiotic resistance in IE pathogens and new patterns of disease ensure that the management of IE remains a challenge.

Since 1955, both national and international guidelines have evolved to aid the prophylaxis, diagnosis and treatment of this important disease. However, the nature of IE ensures that the evidence base from which these guidelines have traditionally been derived is limited to case–control cohort studies, animal data and expert consensus opinion. For both practical and ethical reasons, no large, well-designed, randomised controlled trial has been conducted on either prophylaxis or treatment of IE. Despite the absence of a strong evidence base, antibiotic prophylaxis before a range of dental and other surgical procedures in susceptible populations is universally practised in the developed world.

Recently, the European Society of Cardiology (ESC),¹ British Cardiac Society/Royal College of Physician (BCS/RCP)² and American Heart Association (AHA)³ have all released new guidelines on the diagnosis and treatment of IE, with the ESC and BCS/RCP also including guidance on IE prophylaxis. Revised guidelines on the subject of IE prophylaxis alone have also been published by the Société Française de Cardiologie (SFC).^4,5 (Excerpts from the four guidelines on prophylaxis of IE have been summarised as webtables 1–4; to view these tables visit the Heart website— http://heart.bmj.com/supplemental.) The guidelines demonstrate concordance on a wide majority of issues, with some key exceptions. A discussion of the evidence behind these exceptions contributes to the consensus-building process important for guideline implementation.

Shifting patterns of disease have prompted this international guideline review process. Recent epidemiological trends include a rise in the incidence of staphylococcal skin flora observed as the culprit pathogen, both …