title: Is there an association between clinical presentation and the location and extent of myocardial involvement of cardiac sarcoidosis as assessed by ¹⁸F- fluorodoexyglucose positron emission tomography?
abstract: BACKGROUND
  Positron emission tomography using (18)F-Fluorodeoxyglucose (FDG) is an emerging modality for diagnosis of cardiac sarcoidosis (CS). We compared the location and degree of FDG uptake in CS patients presenting with either advanced atrioventricular block (AVB) or ventricular tachycardia (VT).
  
  
  RESULTS
  We included consecutive patients who presented with either AVB or VT with a diagnosis of CS. A cohort of patients with clinically silent CS was included as controls. FDG activity was quantified as standardized uptake values (SUV) and both the overall mean left ventricular (LV) SUV as well as the Maximum Mean Segmental SUV was recorded for each patient. Receiver operator characteristic (ROC) analysis was performed to identify cutoff SUV values that best identified patients with VT. A total of 27 patients with CS were included (13 females; mean age, 56 ± 8 years; 8 VT, 12 AVB, and 7 controls). Both mean LV SUV and Max SUV in CS patients presenting with VT were significantly higher compared with those with AVB (mean SUV: VT median 5.33, range 4.7-9.35 versus AVB median 2.48, range 0.86-8.59, P=0.016; max SUV: VT median 11.07, range 9.24-14.4 versus AVB median 5.63, range 3.42-15.71, P=0.005) and compared with controls. There was no significant difference in SUV values between AVB patients and controls. ROC analysis for identification of patients with VT showed AUCs of 0.93 and 0.895 for a mean LV SUV of >3.42 and a max SUV >8.56, respectively (P<0.001).
  
  
  CONCLUSIONS
  CS patients with VT displayed significantly higher FDG uptake when compared with those with AVB and asymptomatic controls. Further prospective studies are required to evaluate this finding.
authors.affiliation: Arrhythmia Service, Cardiac Research and Methods Center, and the National Cardiac PET Centre, Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute; and the Division of Nuclear Medicine, Department of Medicine, The Ottawa Hospital and University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Brian A
authors.initials: BA
authors.lastname: Mc Ardle
authors.forename: David H
authors.initials: DH
authors.lastname: Birnie
authors.forename: Ran
authors.initials: R
authors.lastname: Klein
authors.forename: Rob A
authors.initials: RA
authors.lastname: de Kemp
authors.forename: Eugene
authors.initials: E
authors.lastname: Leung
authors.forename: Jennifer
authors.initials: J
authors.lastname: Renaud
authors.forename: Jean
authors.initials: J
authors.lastname: DaSilva
authors.forename: George A
authors.initials: GA
authors.lastname: Wells
authors.forename: Rob S
authors.initials: RS
authors.lastname: Beanlands
authors.forename: Pablo B
authors.initials: PB
authors.lastname: Nery
mesh_terms: D000328:Adult; D000368:Aged; D019540:Area Under Curve; D054537:Atrioventricular Block / Q000000981:diagnostic imaging / Q000209:etiology; D009202:Cardiomyopathies / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016022:Case-Control Studies; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D064847:Multimodal Imaging; D055420:Perfusion Imaging; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D012372:ROC Curve; D019275:Radiopharmaceuticals; D012042:Registries; D012507:Sarcoidosis / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D013318:Stroke Volume; D017180:Tachycardia, Ventricular / Q000000981:diagnostic imaging / Q000209:etiology; D014057:Tomography, X-Ray Computed; D016277:Ventricular Function, Left
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: fluorodeoxyglucose F18; positron emission tomography; sarcoidosis