title: Time-resolved three-dimensional contrast-enhanced magnetic resonance angiography in patients who have undergone a Fontan operation or bidirectional cavopulmonary connection: initial experience.
abstract: OBJECTIVE
  To evaluate the usefulness of time-resolved three-dimensional (3D) magnetic resonance angiography (MRA) using diluted contrast agent (CA) in patients who had undergone a Fontan operation or bidirectional cavopulmonary connection (BCPC).
  
  
  METHODS
  Time-resolved 3D MRA (10 dynamic data sets, two seconds per dynamic data set) using parallel imaging and keyhole data sampling was performed on 15 patients (median age=10 years, range=1-20 years) who had undergone a Fontan operation (N=11) or BCPC (N=4). Diluted gadolinium (Gd) contrast agent (CA) was intravenously injected into the arm and/or leg veins. The flow dynamics and morphology of pulmonary circulation, and lung perfusion were assessed.
  
  
  RESULTS
  Preferential or balanced pulmonary blood flow from each systemic vein was visualized on time-resolved 3D MRA in all patients. In addition, occlusion/stenosis of the central thoracic vein (N=4) and pulmonary artery (N=6), systemic venous (N=5) and arterial (N=6) collaterals, and lung perfusion defect (N=4) were identified. Persistent hepatic venous plexus, pulmonary arteriovenous malformation, and axillary arteriovenous fistula were delineated in three patients, respectively.
  
  
  CONCLUSIONS
  Time-resolved 3D MRA with diluted CA is useful for evaluating patients who have undergone a Fontan operation or BCPC because it can reveal the flow dynamics and morphology of pulmonary circulation, and lung perfusion status.
authors.affiliation: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea. hwgoo@amc.seoul.kr
authors.forename: Hyun Woo
authors.initials: HW
authors.lastname: Goo
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Yang
authors.forename: In-Sook
authors.initials: IS
authors.lastname: Park
authors.forename: Jae Kon
authors.initials: JK
authors.lastname: Ko
authors.forename: Young Hwee
authors.initials: YH
authors.lastname: Kim
authors.forename: Dong-Man
authors.initials: DM
authors.lastname: Seo
authors.forename: Tae-Jin
authors.initials: TJ
authors.lastname: Yun
authors.forename: Jeong-Jun
authors.initials: JJ
authors.lastname: Park
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003251:Constriction, Pathologic / Q000175:diagnosis; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D018729:Fontan Procedure; D005682:Gadolinium / Q000008:administration & dosage; D018610:Heart Bypass, Right; D006330:Heart Defects, Congenital / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D021621:Imaging, Three-Dimensional; D007223:Infant; D018810:Magnetic Resonance Angiography / Q000379:methods; D008297:Male; D011652:Pulmonary Circulation / Q000502:physiology*; D011856:Radiographic Image Enhancement; D013909:Thorax / Q000098:blood supply
chemical_list: D003287:Contrast Media; D005682:Gadolinium