81 - Prosthetic Valve Endocarditis

Abstract

Prosthetic valve endocarditis (PVE) is an uncommon but potentially life-threatening infection that involves a valve prosthesis or annuloplasty ring. Early-onset (illness onset within 1 year) PVE is usually caused by microorganisms acquired perioperatively, such as Staphylococcus aureus and coagulase-negative staphylococci (CoNS). Nosocomial gram-negative pathogens, enterococci, and fungi may rarely cause early-onset PVE. Late-onset PVE is usually caused by organisms that are part of endogenous microbiota such as viridans-group streptococci and enterococci. S. aureus and CoNS are now common pathogens of late-onset PVE, owing in part to an increase in frequency of health care–associated exposure in the late period. Modified Duke criteria have been validated clinically to evaluate patients for diagnosing PVE. Blood cultures are critical; the identification of microbial pathogens and drug susceptibility testing are crucial to selection of appropriate pathogen-directed antibiotic therapy. Transesophageal echocardiography (TEE) is the preferred imaging modality to support a diagnosis and to identify complications that may warrant surgical intervention. Parenteral antimicrobial therapy specifically targeting the identified pathogen for a minimum of 6 weeks is recommended. Early surgical intervention should be considered in complicated PVE with perivalvular extension, severe heart failure, severe valve dysfunction/dehiscence, multiple emboli, antimicrobial unresponsive infection, and PVE due to multidrug-resistant organisms or fungi. Perioperative antibiotic prophylaxis, strict infection control measures, good surgical technique, and limiting the use of central venous catheters are important in preventing early-onset PVE. Antibiotic prophylaxis is recommended for any dental procedure that involves manipulation of the gingival or periapical region of teeth or perforation of oral mucosa.