title: Determination of location, size, and transmurality of chronic myocardial infarction without exogenous contrast media by using cardiac magnetic resonance imaging at 3 T.
abstract: BACKGROUND
  Late-gadolinium-enhanced (LGE) cardiac MRI (CMR) is a powerful method for characterizing myocardial infarction (MI), but the requisite gadolinium infusion is estimated to be contraindicated in ≈20% of patients with MI because of end-stage chronic kidney disease. The purpose of this study is to investigate whether T1 CMR obtained without contrast agents at 3 T could be an alternative to LGE CMR for characterizing chronic MIs using a canine model of MI.
  
  
  RESULTS
  Canines (n=29) underwent CMR at 7 days (acute MI [AMI]) and 4 months (chronic MI [CMI]) after MI. Infarct location, size, and transmurality measured by using native T1 maps and LGE images at 1.5 T and 3 T were compared. Resolution of edema between AMI and CMI was examined with T2 maps. T1 maps overestimated infarct size and transmurality relative to LGE images in AMI (P=0.016 and P=0.007, respectively), which was not observed in CMI (P=0.49 and P=0.81, respectively) at 3 T. T1 maps underestimated infarct size and transmurality relative to LGE images in AMI and CMI (P<0.001) at 1.5 T. Relative to the remote territories, T1 of the infarcted myocardium was increased in CMI and AMI (P<0.05), and T2 of the infarcted myocardium was increased in AMI (P<0.001) but not in CMI (P>0.20) at both field strengths. Histology showed extensive replacement fibrosis within the CMI territories. CMI detection sensitivity and specificity of T1 CMR at 3 T were 95% and 97%, respectively.
  
  
  CONCLUSIONS
  Native T1 maps at 3 T can determine the location, size, and transmurality of CMI with high diagnostic accuracy. Patient studies are necessary for clinical translation.
authors.affiliation: From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.).
authors.forename: Avinash
authors.initials: A
authors.lastname: Kali
authors.affiliation: From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.).
authors.forename: Ivan
authors.initials: I
authors.lastname: Cokic
authors.affiliation: From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.).
authors.forename: Richard L Q
authors.initials: RL
authors.lastname: Tang
authors.affiliation: From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.).
authors.forename: Hsin-Jung
authors.initials: HJ
authors.lastname: Yang
authors.affiliation: From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.).
authors.forename: Behzad
authors.initials: B
authors.lastname: Sharif
authors.affiliation: From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.).
authors.forename: Eduardo
authors.initials: E
authors.lastname: Marbán
authors.affiliation: From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.).
authors.forename: Debiao
authors.initials: D
authors.lastname: Li
authors.affiliation: From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.).
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Berman
authors.affiliation: From the Biomedical Imaging Research Institute, Department of Biomedical Sciences (A.K., I.C., R.L.Q.T., H.-J.Y., B.S., D.L., R.D.) and Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA (E.M., D.L., D. S. B., R.D.); Department of Bioengineering (A.K., H.-J.Y.) and Department of Medicine, David Geffen School of Medicine (D. S. B., R.D.), University of California, Los Angeles, CA; and Department of Radiology, Northwestern University, Chicago, IL (A.K., R.L.Q.T., D.L., R.D.). rohandkumar@csmc.edu.
authors.forename: Rohan
authors.initials: R
authors.lastname: Dharmakumar
mesh_terms: D000818:Animals; D002908:Chronic Disease; D003287:Contrast Media; D004195:Disease Models, Animal; D004285:Dogs; D005500:Follow-Up Studies; D019786:Gadolinium DTPA; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000473:pathology; D009206:Myocardium; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA
keywords: fibrosis; myocardial infarction