Infective endocarditis has always fascinated clinicians, but until 2006 it had rarely caused fisticuffs. In that year, the British Society for Antimicrobial Chemotherapy produced guidelines on the prevention of endocarditis,1 which incensed the British Cardiac Society, apparently causing “dismay among cardiologists and confusion among patients and dentists.”2 The major change was the recommendation to restrict antibiotic prophylaxis to patients judged to be at highest risk. The British Cardiac Society countered by arranging for the National Institute for Health and Clinical Excellence (NICE) to review matters. As a result, NICE has published its own guidelines. Ironically, the draft version received scathing criticism via the British Cardiac Society’s …