title: Molecular magnetic resonance imaging of atrial clots in a swine model.
abstract: BACKGROUND
  The detection and differentiation of intracardiac masses is still challenging and may include neoplasms and thrombi. The aim of this study was the investigation of a targeted, fibrin-specific contrast agent (EP-2104R) for molecular targeted magnetic resonance imaging (MRI) of left atrial clots.
  
  
  RESULTS
  Chronic human thrombi were surgically implanted in the left atrial appendage of 5 swine. Molecular MRI was performed with a navigator-gated, free-breathing, cardiac-triggered 3D inversion-recovery, black-blood, gradient-echo sequence before and after systemic administration of 4 micromol/kg EP-2104R. MR images were analyzed by 2 investigators, and the contrast-to-noise ratio was calculated. Location of clots was confirmed by autopsy, and the gadolinium concentration in the clots was assessed. Before contrast agent administration, thrombi were not visible on black-blood MR images. After contrast administration, all atrial clots (n=5) were selectively visualized as white spots with a high contrast-to-noise ratio (clot/blood, 29.7+/-8.0). The gadolinium concentration in the clots averaged 74+/-45 micromol/L.
  
  
  CONCLUSIONS
  The fibrin-specific MR contrast agent EP-2104R allows for selective and high-contrast visualization of left atrial clots by means of molecular targeted MRI.
authors: Department of Diagnostic Radiology, Aachen Technical University, Aachen, Germany. spuenti@rad.rwth-aachen.de
authors: Elmar
authors: E
authors: Spuentrup
authors: Bernd
authors: B
authors: Fausten
authors: Sylvia
authors: S
authors: Kinzel
authors: Andrea J
authors: AJ
authors: Wiethoff
authors: Rene M
authors: RM
authors: Botnar
authors: Philip B
authors: PB
authors: Graham
authors: Stephan
authors: S
authors: Haller
authors: Marcus
authors: M
authors: Katoh
authors: Edward C
authors: EC
authors: Parsons
authors: Warren J
authors: WJ
authors: Manning
authors: Thomas
authors: T
authors: Busch
authors: Rolf W
authors: RW
authors: Günther
authors: Arno
authors: A
authors: Buecker
mesh_terms: D000818:Animals; D006325:Heart Atria; D006331:Heart Diseases / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D023421:Models, Animal; D013552:Swine; D013927:Thrombosis / Q000175:diagnosis*