Pictorial Essay of [18F]FDG PET/CT in the Evaluation of Suspected Infection of Cardiac Devices and Infective Endocarditis: Patient Preparation, Pathophysiologic Findings, and Interpretation.

In addition to the standard viability assessment, cardiac [18F]FDG PET/CT is used in cases of infection, inflammation, innervation, and infiltrative pathologies. Unlike for myocardial viability assessment, these conditions require a specific patient preparation protocol aimed at suppressing physiologic myocardial glucose uptake. Despite adequate patient preparation, various patterns of [18F]FDG uptake are noted in the myocardium, which correlate with the cardiac physiology as reflected by the clinical, echocardiographic, and anatomic findings. Surgical manipulation with implantation of various prosthetic devices for conditions such as congenital heart disease, valvular pathologies, conduction abnormalities, and ischemic heart diseases make diagnostic imaging challenging because of the complex anatomy and presence of highly attenuating material. The high sensitivity of [18F]FDG PET/CT to detect physiologic alterations-such as in cases of infection, inflammation, or infiltration, despite the altered anatomy or presence of highly attenuating material-makes [18F]FDG PET/CT an essential tool for early and accurate diagnosis. This illustrative communication aims to highlight the different patterns of [18F]FDG uptake in various pathophysiologic conditions of the heart and in infection of prosthetic cardiac devices.