Guidelines for Preventing Infective Endocarditis

For more than 50 years, the standard of care for preventing infective endocarditis (IE) in “at-risk” patients has been to administer antibiotic prophylaxis before gastrointestinal endoscopic procedures. However, little evidence supports this long-standing American Heart Association recommendation. Now, a task force of experts from the Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee from the AHA, along with an international group of experts, reviewed data on the efficacy of prophylaxis to prevent IE in patients who undergo dental, GI, or genitourinary (GU) procedures.

IE results from a complex interaction between a bloodstream pathogen and the target site of endocardial-cell damage. This interaction occurs through formation of a nonbacterial thrombus, followed by bacteremia and adherence of bacteria to the thrombus, and, then, proliferation of bacteria within the vegetation. Early case reports and observational studies pointed to a possible association between release of streptococci and enterococci from dental, GI, or GU procedures and development of IE. However, the task force did not find good evidence to support dental IE prophylaxis in any patients except those at highest risk (characterization of “high-risk” patients was refined and limited to people with prosthetic cardiac valves, previous IE, some forms of congenital heart disease, and cardiac transplants with cardiac valvulopathy). The task force concluded that daily activities (e.g., teeth brushing, defecation) were more likely to cause bacteremia than were dental or endoscopic procedures. Because no credible data exist to support an association between IE and GI or GU procedures, administration of antibiotics solely to prevent IE is not recommended for patients who will undergo endoscopy or colonoscopy. Of note, the authors also stated that no evidence supports antibiotic prophylaxis in patients who have undergone recent coronary-artery bypass surgery or coronary stenting. Use of antibiotics for prevention of prosthetic-joint infection was beyond the scope of this report.