title: Quantification of Myocardial Extracellular Volume Fraction with Cardiac MR Imaging in Thalassemia Major.
abstract: Purpose To quantify myocardial extracellular volume (ECV) by using cardiac magnetic resonance (MR) imaging in thalassemia major and to investigate the relationship between ECV and myocardial iron overload. Materials and Methods With institutional review board approval and informed consent, 30 patients with thalassemia major (mean age ± standard deviation, 34.6 years ± 9.5) and 10 healthy control subjects (mean age, 31.5 years ± 4.4) were prospectively recruited (clinicaltrials.gov identification number NCT02090699). Nineteen patients (63.3%) had prior myocardial iron overload (defined as midseptal T2* < 20 msec on any prior cardiac MR images). Cardiac MR imaging at 1.5 T included cine steady-state free precession for ventricular function, T2* for myocardial iron quantification, and unenhanced and contrast material-enhanced T1 mapping. ECV was calculated with input of the patient's hematocrit level. Peak systolic global longitudinal strain by means of speckle tracking was assessed with same-day transthoracic echocardiography. Statistical analysis included use of the two-sample t test, Fisher exact test, and Spearman correlation. Results Unenhanced T1 values were significantly lower in patients with prior myocardial iron overload than in control subjects (850.3 ± 115.1 vs 1006.3 ± 35.4, P < .001) and correlated strongly with T2* values (r = 0.874, P < .001). Patients with prior myocardial iron overload had higher ECV than did patients without iron overload (31.3% ± 2.8 vs 28.2% ± 3.4, P = .030) and healthy control subjects (27.0% ± 3.1, P = .003). There was no difference in ECV between patients without iron overload and control subjects (P = .647). ECV correlated with lowest historical T2* (r = -0.469, P = .010) but did not correlate significantly with left ventricular ejection fraction (r = -0.216, P = .252) or global longitudinal strain (r = -0.164, P = .423). Conclusion ECV is significantly increased in thalassemia major and is associated with myocardial iron overload. These abnormalities may potentially reflect diffuse interstitial myocardial fibrosis. (©) RSNA, 2015 Online supplemental material is available for this article.
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Kate
authors.initials: K
authors.lastname: Hanneman
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Elsie T
authors.initials: ET
authors.lastname: Nguyen
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Paaladinesh
authors.initials: P
authors.lastname: Thavendiranathan
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Richard
authors.initials: R
authors.lastname: Ward
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Andreas
authors.initials: A
authors.lastname: Greiser
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Jolly
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Jagdish
authors.initials: J
authors.lastname: Butany
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Issac Y
authors.initials: IY
authors.lastname: Yang
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Marshall S
authors.initials: MS
authors.lastname: Sussman
authors.affiliation: Department of Medical Imaging (K.H., E.T.N., P.T., I.Y.Y., M.S.S., B.J.W.) and Division of Cardiology (P.T.), Peter Munk Cardiac Centre, University Health Network, University of Toronto, 585 University Ave, NCSB-1C557, Toronto, ON, Canada M5G 2N2; Division of Hematology, Department of Medicine, Toronto General Hospital, University of Toronto, Toronto, Ontario, Canada (R.W.); Siemens AG Healthcare, Erlangen, Germany (A.G.); Department of Corporate Research, Siemens Corporation, Princeton, NJ (M.P.J.); and Division of Pathology, Department of Laboratory Medicine and Pathobiology, University Health Network, University of Toronto, Toronto, Ontario, Canada (J.B.).
authors.forename: Bernd J
authors.initials: BJ
authors.lastname: Wintersperger
mesh_terms: D000328:Adult; D004452:Echocardiography; D006331:Heart Diseases / Q000000981:diagnostic imaging* / Q000209:etiology; D006801:Humans; D019190:Iron Overload / Q000000981:diagnostic imaging* / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D017086:beta-Thalassemia / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology