title: Integrated 18F-FDG PET/MR imaging in the assessment of cardiac masses: a pilot study.
abstract: The objective of the present study was to evaluate whether integrated (18)F-FDG PET/MR imaging could improve the diagnostic workup in patients with cardiac masses.
  
  
  METHODS
  Twenty patients were prospectively assessed using integrated cardiac (18)F-FDG PET/MR imaging: 16 patients with cardiac masses of unknown identity and 4 patients with cardiac sarcoma after surgical therapy. All scans were obtained on an integrated 3-T PET/MR device. The MR protocol consisted of half Fourier acquisition single-shot turbo spin-echo sequence, cine, and T2-weighted images as well as T1-weighted images before and after injection of gadobutrol. PET data were acquired simultaneously with the MR scan after injection of 199 ± 58 MBq of (18)F-FDG. Patients were prepared with a high-fat, low-carbohydrate diet in a period of 24 h before the examination, and 50 IU/kg of unfractionated heparin were administered intravenously 15 min before (18)F-FDG injection.
  
  
  RESULTS
  Cardiac masses were diagnosed as follows: metastases, 3; direct tumor infiltration via pulmonary vein, 1; local relapse of primary sarcoma after surgery, 2; Burkitt lymphoma, 1; scar/patch tissue after surgery of primary sarcoma, 2; myxoma, 4; fibroelastoma, 1; caseous calcification of mitral annulus, 3; and thrombus, 3. The maximum standardized uptake value (SUVmax) in malignant lesions was significantly higher than in nonmalignant cases (13.2 ± 6.2 vs. 2.3 ± 1.2, P = 0.0004). When a threshold of 5.2 or greater was used, SUVmax was found to yield 100% sensitivity and 92% specificity for the differentiation between malignant and nonmalignant cases. T2-weighted hyperintensity and contrast enhancement both yielded 100% sensitivity but a weak specificity of 54% and 46%, respectively. Morphologic tumor features as assessed by cine MR imaging yielded 86% sensitivity and 92% specificity. Consent interpretation using all available MR features yielded 100% sensitivity and 92% specificity. A Boolean 'AND' combination of an SUVmax of 5.2 or greater with consent MR image interpretation improved sensitivity and specificity to 100%.
  
  
  CONCLUSIONS
  In selected patients, (18)F-FDG PET/MR imaging can improve the noninvasive diagnosis and follow-up of cardiac masses.
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany felix.nensa@uk-essen.de.
authors.forename: Felix
authors.initials: F
authors.lastname: Nensa
authors.affiliation: Clinic for Cardiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: Ercan
authors.initials: E
authors.lastname: Tezgah
authors.affiliation: Clinic for Nuclear Medicine, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: Thorsten D
authors.initials: TD
authors.lastname: Poeppel
authors.affiliation: Department of Cardiology and Angiology, Contilia Heart and Vascular Center, Elisabeth Hospital Essen, Essen, Germany.
authors.forename: Christoph J
authors.initials: CJ
authors.lastname: Jensen
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: Juliane
authors.initials: J
authors.lastname: Schelhorn
authors.affiliation: Department of Medicine (Cancer Research), West German Tumor Center, University Hospital of University Duisburg-Essen, Essen, Germany; and.
authors.forename: Jens
authors.initials: J
authors.lastname: Köhler
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Dusseldorf, University of Dusseldorf, Dusseldorf, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Heusch
authors.affiliation: Department of Cardiology and Angiology, Contilia Heart and Vascular Center, Elisabeth Hospital Essen, Essen, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Bruder
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Schlosser
authors.affiliation: Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Nassenstein
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D019788:Fluorodeoxyglucose F18; D005583:Fourier Analysis; D006321:Heart / Q000000981:diagnostic imaging*; D006338:Heart Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D006493:Heparin / Q000627:therapeutic use; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009362:Neoplasm Metastasis; D010865:Pilot Projects; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D012372:ROC Curve; D055815:Young Adult
chemical_list: D019788:Fluorodeoxyglucose F18; D006493:Heparin
keywords: 18F-FDG; PET/MRI; cardiac malignancy; cardiac tumor