title: Cardiac magnetic resonance angiography using blood-pool contrast agents: comparison of citrate-coated very small superparamagnetic iron oxide particles with gadofosveset trisodium in pigs.
abstract: OBJECTIVE
  To compare citrate-coated very small superparamagnetic iron oxide particles (VSOP) with gadofosveset trisodium as blood pool contrast agents for cardiac magnetic resonance angiography (CMRA) in pigs.
  
  
  METHODS
  Animal experiments were approved by the responsible authority. 10 CMRA-like examinations were performed at 1.5 T after administration of VSOP (0.06  mmol Fe/kg; 5 examinations) and gadofosveset trisodium (0.03  mmol Gd/kg; 5 examinations). The CMRA protocol included ECG-gated inversion-recovery-prepared T1-weighted gradient echo imaging (IR-GRE; one slice) and ECG-gated inversion recovery prepared steady state free precession imaging (IR SSFP; one slice) before and 1, 3, 5, 10, 15, 20, 25, 30, 40, 50, and 60  min after injection. At each time point, three different inversion times (TI; 200  msec, 300  msec, and 400  msec) were applied. Contrast-to-noise ratios (CNR) between blood and myocardium were calculated and compared using mixed linear models.
  
  
  RESULTS
  No significant differences of CNR were found between IR-GRE and IR SSFP. At 3 and 5  min after contrast agent administration, VSOP showed a significantly higher CNR than gadofosveset trisodium when TI of 200  msec and 300 msec were applied (TI of 200  msec at 3 min: 8.2 ± 0.7 vs. 5.4 ± 0.7; TI of 200  msec at 5 min: 7.9 ± 0.7 vs. 3.5 ± 0.8; TI of 300  msec at 3  min: 11.7 ± 0.7 vs. 8.8 ± 0.8; TI of 300  msec at 5  min: 11.4 ± 0.7 vs. 8.0 ± 0.8; p < 0.05). Moreover, significant differences in favor of VSOP were found for all time points from 10 to 40  min irrespective of TI (p < 0.05).
  
  
  CONCLUSIONS
  VSOP has superior blood-pool properties compared to gadofosveset trisodium resulting in prolonged improvement of CNR on CMRA.
authors.affiliation: Institut für Radiologie, Charité-Universitätsmedizin Berlin.
authors.forename: J
authors.initials: J
authors.lastname: Schnorr
authors.forename: M
authors.initials: M
authors.lastname: Taupitz
authors.forename: E A
authors.initials: EA
authors.lastname: Schellenberger
authors.forename: C
authors.initials: C
authors.lastname: Warmuth
authors.forename: U L
authors.initials: UL
authors.lastname: Fahlenkamp
authors.forename: S
authors.initials: S
authors.lastname: Wagner
authors.forename: N
authors.initials: N
authors.lastname: Kaufels
authors.forename: M
authors.initials: M
authors.lastname: Wagner
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000008:administration & dosage*; D017023:Coronary Angiography / Q000379:methods*; D052203:Ferrosoferric Oxide; D005682:Gadolinium; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D009942:Organometallic Compounds; D012680:Sensitivity and Specificity; D013552:Swine
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C427127:superparamagnetic blood pool agent; D005682:Gadolinium; D052203:Ferrosoferric Oxide; C109932:gadofosveset trisodium