Cardiovascular implantable electronic device infection: delayed vs standard FDG PET-CT imaging

Abstract

Delayed FDG PET-CT imaging should be considered at least in patients with negative 1-hour scan and founded suspicion of pacing lead infection.

18F-FDG PET/CT now endorsed by guidelines across all types of CIED infection: Evidence limited but growing

“…Contemporary studies have optimized patient preparation through use of dietary carbohydrate restriction, thereby reducing physiological myocardial 18 F-FDG uptake, making it easier to identify pathological uptake. [20][21][22][23][24][25] The current meta-analysis examined a subgroup of studies that utilized appropriate dietary preparation (?/-heparin) and show that the sensitivity of 18 F-FDG PET/CT for detecting CIED infection was substantially increased (to 92%) using this strategy. 15 This development represents a milestone in the advancement of metabolic imaging of cardiovascular infection and has possibly contributed to increasing clinician confidence in reporting on the extent of intracardiac extension of infection.…”

Another potential step to improve prosthetic heart valve endocarditis imaging with 18F-FDG PET/CT

“…Conversely, the late image acquisition assumes a persistent glucose influx in inflammatory activated cells and further clearance of glucose or FDG from the blood pool yielding a higher contrast between activity in infected regions and background. 2 Previous investigations 2,3 have indeed suggested late imaging to add diagnostic value in the identification of infected cardiovascular implants. As the authors point out, the case description reported by Caldarella 2 are in agreement with the one false-positive finding in the current investigation on late imaging.…”

“…cardiac implantable electronic device lead infection may reflect a different inflammatory disease entity for which late image acquisition in fact appear to be more suitable. [3][4][5] As regards the quantification of the FDG uptake, maximal standard unit value (SUV max) and target-to-background ratio (TBR) between standard and late image acquisition unraveled a great variability in the individual measurements resulting in a wide overlap between both groups with PVE and non-PVE. 1 Such finding emphasizes that even uninfected PHVs may have a certain amount of sterile inflammation, reflecting post-surgical tissue response and/or a mild foreign body reaction depending on the post-interventional period.…”

Radionuclide Imaging of Infective Endocarditis: State of Art and Future Perspective

“…However, the use of antimicrobial should be taken into account during imaging interpretation since they might affect the intensity of FDG uptake due to their immunomodulatory effect [7]. Late PET/CT imaging (2-3 h after FDG injection) should be considered in patients when negative 1-h PET/Ct scan in maximizing the contrast between septic foci and background [33].…”