title: The response of FDG uptake to immunosuppressive treatment on FDG PET/CT imaging for cardiac sarcoidosis.
abstract: Immunosuppression is used to treat cardiac sarcoidosis, despite limited data. FDG PET/CT is used for detecting cardiac inflammation in patients with CS, yet there is variability in interpretation of FDG PET/CT. Our aim was to compare quantitative and qualitative interpretation of FDG PET/CT for CS in defining the FDG response to immunosuppression.
  
  
  
  Patients with CS (N = 43 total studies from 17 patients) had serial FDG PET/CT studies before/after immunosuppression. FDG uptake was analyzed qualitatively (visually; FDG-positive segments) and quantitatively (SUVmax; cardiac metabolic volume and activity (CMV, CMA); volume above SUV thresholds 2.7 and 4.1 g/mL). Complete resolution of FDG uptake was common using CMA (10/17), CMV (10/17), but a 2.7 g/mL SUV threshold (13/17) and SUVmax (14/17) were more likely to define partial responses. In six patients imaged after a reduction in immunosuppression, 4/6 had a rebound quantitative FDG uptake.
  
  
  
  Quantitative interpretation of FDG PET/CT in CS can detect changes in FDG uptake in response to immunosuppression. Further studies are needed to see if quantitative changes in FDG uptake are associated with improved outcomes.
authors.affiliation: Section of Cardiovascular Medicine, Department of Internal Medicine, Boston University School of Medicine, Boston, MA, USA.
authors.forename: Azadeh
authors.initials: A
authors.lastname: Ahmadian
authors.affiliation: Department of Internal Medicine, Boston Medical Center and Boston University School of Medicine, Boston, MA, USA.
authors.forename: Sumeet
authors.initials: S
authors.lastname: Pawar
authors.affiliation: Section of Pulmonary, Allergy, Sleep and Critical Care Medicine, Department of Internal Medicine, Boston University School of Medicine, Boston, MA, USA.
authors.forename: Praveen
authors.initials: P
authors.lastname: Govender
authors.affiliation: Section of Pulmonary, Allergy, Sleep and Critical Care Medicine, Department of Internal Medicine, Boston University School of Medicine, Boston, MA, USA.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Berman
authors.affiliation: Section of Cardiovascular Medicine, Department of Internal Medicine, Boston University School of Medicine, Boston, MA, USA.
authors.forename: Frederick L
authors.initials: FL
authors.lastname: Ruberg
authors.affiliation: Section of Cardiovascular Medicine, Department of Internal Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT, 06520, USA. edward.miller@yale.edu.
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Miller
mesh_terms: D009202:Cardiomyopathies / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000378:metabolism*; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics*; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D008297:Male; D008657:Metabolic Clearance Rate / Q000187:drug effects; D008875:Middle Aged; D015588:Observer Variation; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012507:Sarcoidosis / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000378:metabolism*; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D007166:Immunosuppressive Agents; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Glucose; PET/CT imaging; fluorodeoxyglucose (FDG); inflammation; metabolism: PET