82 - Infections of Nonvalvular Cardiovascular Devices

Abstract

Nonvalvular cardiovascular devices are increasingly being used in clinical practice. These include cardiovascular implantable electronic devices (CIEDs), mechanical circulatory assist devices, and prosthetic vascular grafts, among others. Despite improvements in device manufacturing and increasing experience of implanting physicians, infection remains a significant issue and is associated with significant morbidity, cost, and mortality. Clinical manifestations of nonvalvular cardiovascular device infections vary, and these patients may present with inflammatory changes limited to the device site or systemic infection, frequently complicated by bloodstream infection. Blood cultures should be obtained before starting any empirical antimicrobial therapy in all patients with suspected cardiovascular device infection. Transesophageal echocardiography is the test of choice for detecting vegetations on CIED leads, whereas computed tomography combined with angiography is the primary imaging modality for vascular graft, particularly intracavitary graft, infections. Nuclear imaging, especially positron emission tomography, is an emerging modality to confirm or exclude CIED, left ventricular assist device, and vascular graft infections. The majority of these nonvalvular cardiovascular device infections are caused by staphylococci that tend to produce microbial biofilms on device surfaces, making it difficult for antibiotics to reach the microbes embedded in this slime layer and exert their microbicidal activity. This frequently necessitates hardware removal, along with prolonged courses of parenteral antimicrobial therapy, to eradicate infection. For patients who are not candidates for device removal, chronic suppressive antimicrobial therapy is frequently prescribed, with variable success rates.