title: Comparison of Low-Dose Higher-Relaxivity and Standard-Dose Lower-Relaxivity Contrast Media for Delayed-Enhancement MRI: A Blinded Randomized Crossover Study.
abstract: OBJECTIVE
  The gadolinium-based MRI contrast agent gadobenate dimeglumine has nearly twice the MR relaxivity of gadopentetate dimeglumine at 1.5 T. The purpose of this study was to determine whether a lower dose (0.1 mmol/kg) of gadobenate dimeglumine can be used to obtain delayed-enhancement MR images comparable to those obtained with a standard dose (0.2 mmol/kg) of gadopentetate dimeglumine.
  
  
  METHODS
  In this blinded randomized crossover study, 20 patients with known myocardial infarction underwent two separate delayed-enhancement MRI examinations after receiving 0.1 mmol/kg gadobenate dimeglumine and 0.2 mmol/kg gadopentetate dimeglumine (random administration). The conspicuity of lesion enhancement 5, 10, and 20 minutes after contrast administration was quantified as relative enhancement ratio (RER).
  
  
  RESULTS
  With either gadolinium-based contrast agent, damaged myocardium had higher signal intensity than normal remote myocardium (RER > 4) on delayed-enhancement MR images, and the blood RER declined over time after contrast administration. The blood RER was not significantly higher for gadobenate dimeglumine than for gadopentetate dimeglumine at 5 and 10 minutes. Nevertheless, there was a larger reduction in blood RER for gadobenate dimeglumine than for gadopentetate dimeglumine between 5 and 10 minutes and between 10 and 20 minutes. The volumes of enhancement were similar for gadobenate dimeglumine (13.6 ± 8.8 cm(3)) and gadopentetate dimeglumine (13.5 ± 8.9 cm(3)) (p = 0.98). The mean difference in Bland-Altman analysis for delayed-enhancement volume between the agents was 0.1 cm(3).
  
  
  CONCLUSIONS
  Qualitatively and quantitatively, delayed-enhancement MR images of ischemic myocardium obtained with 0.1 mmol/kg gadobenate dimeglumine are comparable to those obtained with 0.2 mmol/kg gadopentetate dimeglumine 5, 10, and 20 minutes after contrast administration.
authors: 1 Department of Diagnostic and Interventional Radiology, CHI St. Luke's Medical Center and the Texas Heart Institute, 6720 Bertner Ave, MC 2-270, Houston, TX 77030.|2 Department of Cardiology, The Texas Heart Institute and CHI St. Luke's Medical Center, Houston, TX.|3 Department of Diagnostic and Interventional Radiology, The Texas Heart Institute and CHI St. Luke's Medical Center, Houston, TX.|4 Department of Medicine, Baylor College of Medicine, Houston, TX.
authors: Benjamin Y C
authors: BY
authors: Cheong
authors: 1 Department of Diagnostic and Interventional Radiology, CHI St. Luke's Medical Center and the Texas Heart Institute, 6720 Bertner Ave, MC 2-270, Houston, TX 77030.
authors: Cihan
authors: C
authors: Duran
authors: 5 Department of Cardiovascular Surgery, The Texas Heart Institute and CHI St. Luke's Medical Center, Houston, TX.|6 Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX.
authors: Ourania A
authors: OA
authors: Preventza
authors: 1 Department of Diagnostic and Interventional Radiology, CHI St. Luke's Medical Center and the Texas Heart Institute, 6720 Bertner Ave, MC 2-270, Houston, TX 77030.|3 Department of Diagnostic and Interventional Radiology, The Texas Heart Institute and CHI St. Luke's Medical Center, Houston, TX.
authors: Raja
authors: R
authors: Muthupillai
mesh_terms: D000368:Aged; D057791:Cardiac Imaging Techniques / Q000379:methods*; D002318:Cardiovascular Diseases / Q000175:diagnosis*; D003287:Contrast Media / Q000008:administration & dosage*; D018592:Cross-Over Studies; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008536:Meglumine / Q000008:administration & dosage / Q000031:analogs & derivatives*; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage*
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C064572:gadobenic acid; D008536:Meglumine; D019786:Gadolinium DTPA
keywords: cardiovascular MRI; crossover studies; delayed enhancement; gadobenate dimeglumine; gadolinium-based contrast agents; gadopentetate dimeglumine; myocardial scar; randomized controlled trial