Level 3: Lacking direct evidence
Antibiotic prophylaxis is indicated in patients with certain cardiac conditions who are undergoing bacteremia-producing procedures. However, the American Heart Association (AHA) 2007 guidelines recommend antibiotics for fewer conditions and procedures than the 1997 guidelines (Circulation. 2007;116:1736-1754; full-text available online free of charge at: http://circ.ahajournals.org/, accessed October 12, 2007).
Cardiac patients in whom endocarditis prophylaxis is recommended include those with prosthetic heart valves or a history of infective endocarditis (IE), cardiac-transplant recipients who develop cardiac valvulopathy, and those with certain congenital conditions. Endocarditis prophylaxis is not recommended in patients with mitral valve prolapse, rheumatic heart disease, bicuspid valve disease, calcified aortic stenosis, isolated secundum atrial septal defect, previous coronary artery bypass graft surgery, heart murmurs (physiologic, functional, or innocent), certain congenital heart conditions (e.g., ventricular septal defect, atrial septal defect, hypertrophic cardiomyopathy), previous Kawasaki disease without valvular dysfunction, or previous rheumatic fever without valvular dysfunction or in those who have a cardiac pacemaker (intravascular and epicardial) or implanted defibrillator. Additionally, surgical repair of atrial septal defect, ventricular septal defect, or patent ductus arteriosus (without residual beyond six months) is not an indication for prophylaxis.
Procedures for which prophylaxis is recommended include dental work that requires manipulation of gingival tissue or the periapical region of teeth, perforation of oral mucosa, or invasive respiratory tract procedures with incision or biopsy of the respiratory mucosa (consider alternative regimens if suspected infection due to Staphylococcus aureus).
Prophylaxis is not recommended if used solely for the purpose of IE prevention in genitourinary or GI tract procedures (including diagnostic esophagogastroduodenoscopy or colonoscopy) or procedures on skin, skin structure, or musculoskeletal tissue.
Oral amoxicillin (Amoxil) 2 g (50 mg/kg in children) given 30-60 minutes before a procedure is the antibiotic prophylaxis regimen of choice. IM or IV alternatives if a patient is unable to take oral medication include ampicillin 2 g (50 mg/kg in children), cefazolin 1 g (50 mg/kg in children), or ceftriaxone (Rocephin) 1 g (50 mg/kg in children). Alternatives for patients who are allergic to penicillin include clindamycin (Cleocin) 600 mg (20 mg/kg in children), azithromycin (Zithromax, Zmax) or clarithromycin (Biaxin) 500 mg (15 mg/kg in children), or cephalexin (Biocef, Keflex) 2 g (50 mg/kg in children) or other first- or second-generation cephalosporin. If a patient is allergic to penicillin and unable to take oral medication, clindamycin 600 mg (20 mg/kg in children), cefazolin or ceftriaxone 1 g (50 mg/kg in children), or other first- or second-generation cephalosporin are alternatives. Cephalosporin should be used only in persons with no history of anaphylaxis, angioedema, or urticaria with penicillins.