Antibiotic Prophylaxis for Bacterial Endocarditis: An Evolving Story With New Paradigms

The American Heart Association (AHA) Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease has recently completed deliberations on the revision of the 1990-1991 guidelines for endocarditis prophylaxis during bacteremia-inducing procedures.¹ It is anticipated that these new recommendations will receive full AHA sanction, publication, and distribution sometime this year. Although the details of specific regimens are beyond the scope of this letter, the major guideline changes will revolve around 4 predominant themes: (1) antibiotic regimens that are principally oral and that are administered only once in the periprocedural period; (2) limiting the number of cardiac conditions for which uniform antibiotic prophylaxis is recommended only to those with the highest documented risk of endocarditis; (3) assigning cases of endocarditis as "procedure related" only if they occur in a reasonable "incubation period" between the procedure and the onset of symptoms attributable to endocarditis (<2-4 weeks)² and only if the etiologic organism