title: Extracellular volume fraction is more closely associated with altered regional left ventricular velocities than left ventricular ejection fraction in nonischemic cardiomyopathy.
abstract: BACKGROUND
  Nonischemic cardiomyopathy is a common cause of left ventricular (LV) dysfunction and myocardial fibrosis. The purpose of this study was to noninvasively evaluate changes in segmental LV extracellular volume (ECV) fraction, LV velocities, myocardial scar, and wall motion in nonischemic cardiomyopathy patients.
  
  
  RESULTS
  Cardiac MRI including pre- and postcontrast myocardial T1 mapping and velocity quantification (tissue phase mapping) of the LV (basal, midventricular, and apical short axis) was applied in 31 patients with nonischemic cardiomyopathy (50±18 years). Analysis based on the 16-segment American Heart Association model was used to evaluate the segmental distribution of ECV, peak systolic and diastolic myocardial velocities, scar determined by late gadolinium enhancement, and wall motion abnormalities. LV segments with scar or impaired wall motion were significantly associated with elevated ECV (rs =0.26; P<0.001) and reduced peak systolic radial velocities (r=-0.43; P<0.001). Regional myocardial velocities and ECV were similar for patients with reduced (n=12; ECV=0.28±0.06) and preserved left ventricular ejection fraction (n=19; ECV=0.30±0.09). Patients with preserved left ventricular ejection fraction showed significant relationships between increasing ECV and reduced systolic (r=-0.19; r=-0.30) and diastolic (r=0.34; r=0.26) radial and long-axis peak velocities (P<0.001). Even after excluding myocardial segments with late gadolinium enhancement, significant relationships between ECV and segmental LV velocities were maintained indicating the potential of elevated ECV to identify regional diffuse fibrosis not visible by late gadolinium enhancement, which was associated with impaired regional LV function.
  
  
  CONCLUSIONS
  Regionally elevated ECV negatively affected myocardial velocities. The association of elevated regional ECV with reduced myocardial velocities independent of left ventricular ejection fraction suggests a structure-function relationship between altered ECV and segmental myocardial function in nonischemic cardiomyopathy.
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Jeremy
authors.initials: J
authors.lastname: Collins
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Cort
authors.initials: C
authors.lastname: Sommerville
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Patrick
authors.initials: P
authors.lastname: Magrath
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Bruce
authors.initials: B
authors.lastname: Spottiswoode
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Benjamin H
authors.initials: BH
authors.lastname: Freed
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Keith H
authors.initials: KH
authors.lastname: Benzuly
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Robert
authors.initials: R
authors.lastname: Gordon
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Himabindu
authors.initials: H
authors.lastname: Vidula
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Dan C
authors.initials: DC
authors.lastname: Lee
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: Clyde
authors.initials: C
authors.lastname: Yancy
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.).
authors.forename: James
authors.initials: J
authors.lastname: Carr
authors.affiliation: From the Departments of Radiology (J. Collins, C.S., J. Carr, M.M.) and Biomedical Engineering (P.M., M.M.) and Division of Cardiology, Department of Medicine (B.H.F., K.H.B., R.G., H.V., D.C.L., C.Y.), Feinberg School of Medicine, Northwestern University, Chicago, IL; and Siemens Medical Solutions USA, Chicago, IL (B.S.). michael.markl@northwestern.edu.
authors.forename: Michael
authors.initials: M
authors.lastname: Markl
mesh_terms: D000328:Adult; D000368:Aged; D009202:Cardiomyopathies / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D002921:Cicatrix / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D003287:Contrast Media; D005260:Female; D005355:Fibrosis; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D009206:Myocardium / Q000473:pathology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D016277:Ventricular Function, Left; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: cardiomyopathies; fibrosis; magnetic resonance imaging; ventricular function, left