title: 11C-Pittsburgh B PET imaging in cardiac amyloidosis.
abstract: OBJECTIVE
  This study sought to investigate the efficacy of (11)C-Pittsburgh B (PiB) positron emission tomography (PET)/computed tomography (CT) in the diagnosis of cardiac amyloidosis.
  
  
  BACKGROUND
  The PiB compound has been promising for detection of amyloid deposits in the brain.
  
  
  METHODS
  A total of 22 consecutive patients were enrolled in this prospective pilot study of monoclonal gammopathy patients with suspected cardiac amyloidosis. The study consisted of a series of (11)C-PiB PET/CT, echocardiography, cardiac magnetic resonance, and endomyocardial biopsy within a 1-month period. In addition, 10 normal subjects were recruited to determine the most optimal cut-off value for a positive (11)C-PiB PET/CT scan.
  
  
  RESULTS
  Among the 22 patients, 15 patients were diagnosed as cardiac amyloidosis by endomyocardial biopsy and 5 patients had undergone chemotherapy previously before the (11)C-PiB PET/CT. There were no differences in echocardiographic parameters between patients with versus without cardiac amyloidosis, except for a marginal difference in the left ventricular end-diastolic dimension (median 41.0 mm [range 33.0 to 49.0 mm] vs. 50.0 mm [range 38.0 to 55.0 mm], p = 0.066). (11)C-PiB PET/CT was positive in 13 of 15 biopsy-proven cardiac amyloidosis patients, whereas none of the patients without cardiac amyloidosis demonstrated positive (11)C-PiB PET/CT scan results. The maximal myocardium-to-blood cavity ratio was significantly different between patients with versus without cardiac amyloidosis (median 3.9 [range 1.7 to 19.9] vs. 1.0 [range 0.8 to 1.2], p < 0.001). In association with the significant difference of (11)C-PiB uptake in the myocardium between the chemotherapy naïve versus the previous chemotherapy group (median 10.4 [range 1.7 to 19.9] vs. 2.3 [range 1.7 to 3.8], p = 0.014), all except 1 patient among the 5 previously treated patients had responded to chemotherapy by serum free light chain assay results at the time of (11)C-PiB PET/CT scan.
  
  
  CONCLUSIONS
  (11)C-PiB PET/CT may be valuable for the diagnosis of cardiac amyloidosis noninvasively. Whether (11)C-PiB PET/CT may be a good surrogate marker of active light chain deposition in the myocardium warrants further investigation in a larger number of patients.
authors.affiliation: Cardiovascular Center, Seoul National University Hospital, Seoul, Korea; Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Seung-Pyo
authors.initials: SP
authors.lastname: Lee
authors.affiliation: Department of Nuclear Medicine, Seoul National University Hospital and Seoul National University College of Medicine, Seoul, Korea; Department of Molecular Medicine and Biopharmaceutical Sciences, WCU Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Republic of Korea.
authors.forename: Eun Seong
authors.initials: ES
authors.lastname: Lee
authors.affiliation: Department of Nuclear Medicine, Seoul National University Hospital and Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hongyoon
authors.initials: H
authors.lastname: Choi
authors.affiliation: Department of Nuclear Medicine, Seoul National University Hospital and Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Hyung-Jun
authors.initials: HJ
authors.lastname: Im
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Youngil
authors.initials: Y
authors.lastname: Koh
authors.affiliation: Cardiovascular Center, Seoul National University Hospital, Seoul, Korea; Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Min-Ho
authors.initials: MH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Kwon
authors.affiliation: Department of Nuclear Medicine, Seoul National University Hospital and Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Jin Chul
authors.initials: JC
authors.lastname: Paeng
authors.affiliation: Cardiovascular Center, Seoul National University Hospital, Seoul, Korea; Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Hyung-Kwan
authors.initials: HK
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Seoul National University Hospital and Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Gi Jeong
authors.initials: GJ
authors.lastname: Cheon
authors.affiliation: Cardiovascular Center, Seoul National University Hospital, Seoul, Korea; Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Inho
authors.initials: I
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University, Seoul, Korea.
authors.forename: Sung-Soo
authors.initials: SS
authors.lastname: Yoon
authors.affiliation: Department of Pathology, Seoul National University Hospital and Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Jeong-Wook
authors.initials: JW
authors.lastname: Seo
authors.affiliation: Cardiovascular Center, Seoul National University Hospital, Seoul, Korea; Department of Internal Medicine, Seoul National University College of Medicine, Seoul National University, Seoul, Korea. Electronic address: dwsohn@snu.ac.kr.
authors.forename: Dae-Won
authors.initials: DW
authors.lastname: Sohn
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000686:Amyloidosis / Q000175:diagnosis*; D000814:Aniline Compounds; D052160:Benzothiazoles; D009202:Cardiomyopathies / Q000175:diagnosis*; D004452:Echocardiography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D013844:Thiazoles; D014057:Tomography, X-Ray Computed
chemical_list: C475519:2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole; D000814:Aniline Compounds; D052160:Benzothiazoles; D013844:Thiazoles
keywords: Pittsburgh B compound; cardiac amyloidosis; cardiac magnetic resonance; echocardiography; positron emission tomography