The Evolution of Antibiotic Prophylaxis for "Infective Endocarditis".

Dr. Zayed | Published : 17, April 2025.

Infective endocarditis (IE) is a life-threatening infection of the endocardial surface of the heart, predominantly involving native or prosthetic valves. Although rare, its potential for severe morbidity and mortality necessitates a preventive strategy in high-risk individuals. Historically, widespread antibiotic prophylaxis (AP) was recommended for various dental, gastrointestinal (GI), genitourinary (GU), pregnancy and respiratory procedures by AHA back in 1955. However, over decades, growing concerns about antimicrobial resistance, adverse drug reactions, and limited evidence supporting efficacy led to significant revisions of Antibiotic prophylaxis guidelines.

Modern guidelines by the American Heart Association (AHA) and European Society of Cardiology (ESC) emphasize a narrowed approach, recommending AP only for individuals at highest risk of adverse outcomes from IE. These include:

  • Patients with prosthetic cardiac valves (mechanical, bioprosthetic, or transcatheter-implanted)

  • Individuals with a history of prior infective endocarditis

  • Patients with unrepaired cyanotic congenital heart disease (CHD), or repaired CHD with residual shunts or defects adjacent to prosthetic material

  • Cardiac transplant recipients with valvulopathy, such as valvular regurgitation from structural valve disease

Antibiotic prophylaxis is now primarily limited to dental procedures that involve manipulation of gingival tissue, the periapical region of teeth, or perforation of the oral mucosa and does not included Teeth Braces. This stems from the strong association between oral streptococci and IE in susceptible hosts. Conversely GI, GU, and respiratory tract procedures are no longer routinely covered under prophylaxis recommendations unless performed in the presence of active infection or in select high-risk cardiac patients under special conditions, such as manipulation of infected tissue or instrumentation in a septic environment.

Pregnancy, once considered for routine prophylaxis during labor and delivery due to transient bacteremia risk, has now been excluded from AP guidelines. Data indicate that physiological bacteremia during vaginal delivery or cesarean section in otherwise healthy or even moderately at-risk individuals does not pose a significant IE threat to justify antibiotic use.

This evidence-based shift toward precision in prophylaxis reflects a refined understanding of IE pathogenesis, emphasizing host vulnerability over procedural risk alone. The goal is to optimize protection for the truly high-risk cohort while mitigating unnecessary antibiotic exposure to prevent antibiotic resistance, thus preserving microbial ecology and minimizing adverse drug outcomes.

REFERENCES:

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