Management of infectious endocarditis from the perspective of the Infectious Diseases specialist – a 2023 update

An increase in the number and the complexity of cardiac surgery has brought on a rise in the proportion of healthcare-associated Infectious Endocarditis (IE), and as a result, today S. aureus is the most common causative pathogen for this condition. Clinical suspicion for IE should be raised in front of a patient with predisposing risk factors, a new heart murmur and/or vasculitic/embolic events. The Duke Criteria have been long used to diagnose IE. However, they underwent several changes in order to improve their sensitivity in the diagnosis of Q-fever IE and to decrease the size of the possible IE group. Our primary goal is to enhance the knowledge regarding the diagnosis and treatment of infective endocarditis. In acute IE, prior to beginning antibiotic therapy, at least three sets of blood cultures must be taken, ideally from three distinct sites, as determining the etiologic agent is of highest importance. The diagnosis of IE cannot be made based just on a single positive blood culture. To diagnose subacute IE, three to five sets of blood cultures must be drawn over the course of 24 hours. Transthoracic echocardiography (TTE) remains the preferred investigation when the diagnosis of IE is suspected. Transesophageal echocardiography (TOE) is recommended when TTE is unremarkable but the suspicion is still high. A whole-body CT scan, an MRI, a cardiac CT, PET-CT, or radiolabeled leucocyte single-photon emission computed tomography may be helpful when TTE and TOE are inconclusive. Recommended empirical therapy for Native Valve Endocarditis (NVE) and late Prosthetic Valve Endocarditis (PVE) consists of IV Amoxicillin, Oxacillin and Gentamicin administered until blood culture results are available. If a patient is allergic to penicillin, IV Vancomycin and Gentamicin should be given. The recommended empirical antibiotic regimen for early PVE includes IV Vancomycin, Gentamicin, and Rifampin. Once the results of blood cultures are available, the treatment will depend on the isolated organism, its sensitivity to antibiotics, and whether it is an NVE or a PVE.