Imaging of Post-Infarct Inflammation

Longitudinal 18F-FDG PET imaging in a rat model of autoimmune myocarditis

“…Hence, given these drawbacks of 18 F-FDG, other more leukocyte-specific tracers (e.g. 68 Ga-Pentixafor or 18 F-GE180), might be subject of future studies for investigating the inflammatory cascade in myocarditis 7 . Moreover, the small sample size in the CD34/CD44 assessment of the present study limits its statistical power.…”

“…However, functional imaging modalities offer several key advantages in non-invasive inflammatory imaging, e.g. direct interrogation of infiltrating immune cells on a subcellular level 7 . Consequently, the combination of PET and MRI could provide incremental information about myocardial injury and inflammatory activity: in a small cohort of ten patients, simultaneous PET/MRI using 18 F-FDG was feasible to diagnose both cardiac sarcoidosis and myocarditis 36 .…”

“…Recently, the potential of the novel PET probe 11 C-methionine for the assessment of myocardial infiltration in the same autoimmune myocarditis rat model had been investigated: Apart from the longer half-life of 18 F-labelled (110 min) compared to carbon-11 tracers (20.4 min), 18 F-FDG demonstrated a lower uptake in both the liver and the thymus 13 . However, inflammatory PET imaging with 18 F-FDG suffers from several limitations: first, physiological 18 F-FDG uptake in the heart has to be suppressed and common clinical protocols might not work equally for healthy and impaired myocardium 7 . To address these issues, rats were placed on prolonged fasting.…”

“…2-Deoxy-2- 18 F-fluoro-D-glucose ( 18 F-FDG) positron emission tomography (PET) has emerged as a tool for imaging of inflammatory cardiovascular diseases such as myocardial infarction or atherosclerosis 7 . Activated leucocytes, especially macrophages, are known to express high levels of glucose transporters, which result in rapid accumulation of 18 F-FDG at the site of inflammation 8 , 9 .…”

Anti-inflammatory effect of biologic therapy in patients with psoriatic disease: A prospective cohort FDG PET study

“…While FDG PET imaging targets activated macrophages, it is still a non-specific probe that can accumulate in other metabolically active tissues which can therefore introduce interfering background signal. 36 , 37 Imaging of the ascending aorta requires strict dietary preparation to suppress FDG-myocardium uptake (with a high-fat, low-carbohydrate diet prior to PET imaging), given the significant background myocardial FDG uptake which can make it more difficult to differentiate vascular inflammation from background uptake. 38 , 39 FDG PET imaging is also affected by glucose levels, so particular caution in imaging patients with diabetes and hyperglycemia must be employed.…”