According to a focused guideline update specific to patients with valvular heart disease, the ACC and the AHA no longer recommend antimicrobial prophylaxis in most situations.

According to a focused guideline update specific to patients with valvular heart disease, the American College of Cardiology and the American Heart Association no longer recommend antimicrobial prophylaxis in most situations. The guideline update is published in the Journal of the American College of Cardiology for August 19.

Writing Group Chair Dr. Rick A. Nishimura and co-authors note, "Since 1955, the AHA has made recommendations for prevention of infective endocarditis with antimicrobial prophylaxis before specific dental, gastrointestinal (GI), and genitourinary (GU) procedures in patients at risk for its development."

Based on review of clinical and trial data released since 2005, the multidisciplinary team of experts concluded that only a very small number of cases of infective endocarditis are prevented by antibiotic prophylaxis for dental, GI tract, or GU procedures, and that the risk of adverse effects from antibiotic treatment usually exceeds the benefits.

More important than antibiotic prophylaxis, they say, "Maintenance of optimal oral health and hygiene may reduce the incidence of bacteremia from daily activities."

They suggest that endocarditis prophylaxis is reasonable for patients with the highest risk who undergo dental procedures that involve manipulation of gingival tissue or the periapical region of teeth or perforation of the oral mucosa.

Such high risk patients include those with prosthetic cardiac valves or prosthetic materials used for cardiac valve repair, those with previous infective endocarditis, specific patients with coronary heart disease, and cardiac transplant recipients with cardiac valvulopathy.

Antibiotic therapy is also considered reasonable in high-risk patients with infections of the GI or GU tract, to prevent wound infection or sepsis.

The authors do not recommend prophylaxis solely on the basis of an increased risk of infective endocarditis, nor for patients who undergo a GU or GI tract procedure.

Antibiotic prophylaxis is no longer indicated in patients with aortic or mitral stenosis, in adolescents and young adults with congenital valvular heart disease, or in patients with symptomatic or asymptomatic mitral valve prolapse.

The committee notes that these abrupt changes in the AHA guidelines "may cause consternation among patients," and they advise clinicians "to discuss the rationale for these new changes with their patients, including the lack of scientific evidence to demonstrate a proven benefit for infective endocarditis prophylaxis."

They also "understand" that clinicians may want to continue administering prophylaxis for patients with bicuspid aortic valve or coarctation of the aorta, severe mitral valve prolapse, or hypertrophic obstructive cardiomyopathy.

The new guideline update is endorsed by the Society of Cardiovascular Anesthesiologists, the Society for Cardiovascular Angiography and Interventions, and the Society of Thoracic Surgeons.

J Am Coll Cardiol 2008