title: Heterogeneity of myocardial iron distribution in response to chelation therapy in patients with transfusion-dependent anemias.
abstract: The purpose of this study is to examine the effect of different iron chelation regimens on the distribution of myocardial iron in patients with transfusion-dependent anemias. Institutional review board approval was obtained. Patients treated with iron chelation therapy who had undergone baseline and 1-year follow-up cardiac T2* MR studies in a four-year period were identified retrospectively. One hundred and eight patients (44 % male, mean age 31.6 ± 9.7 years) were included. The interventricular septum on three short-axis slices (basal, mid and apical) was divided into anterior and inferior regions of interest for T2* analysis. Cardiac iron concentration (CIC) was calculated from T2* values. Statistical analysis included analysis of variance and paired t-test, using Bonferroni adjustment in all pairwise comparisons. At baseline, T2* measurements varied significantly across all six regions (p < 0.001): lowest in the mid anteroseptum (mean 22.3 ± 10.1 ms) and highest in the apical inferoseptum (mean 26.2 ± 12.8 ms). At follow-up, T2* and CIC values improved significantly in all segments [mean change of 3.78 ms (95 % CI (2.93, 4.62), p < 0.001) and 0.23 mg/g (95 % CI (0.16, 0.29), p < 0.001), respectively]. Change in T2* values varied significantly between segments (p < 0.001) with greatest improvement in the apical inferoseptum [4.26 ms, 95 % CI (2.42, 6.11)] and least improvement in the basal anteroseptum [2.95 ms, 95 % CI (1.37, 4.54)]. The largest improvement in T2* values was noted in patients treated with deferiprone [4.96 ms, 95 % CI (2.34, 7.58)]. There was a statistically significant difference in improvement in CIC values between chelation regimens (p = 0.016). This is the first study to report heterogeneity in response to iron chelating drugs with variable segmental changes in T2* values.
authors.affiliation: Division of Cardiothoracic Imaging, Department of Medical Imaging, University Health Network, Toronto General Hospital, University of Toronto, 585 University Ave., Toronto, ON, M5G 2N2, Canada.
authors.forename: Kate
authors.initials: K
authors.lastname: Hanneman
authors.forename: Vikram M
authors.initials: VM
authors.lastname: Raju
authors.forename: Hadas
authors.initials: H
authors.lastname: Moshonov
authors.forename: Richard
authors.initials: R
authors.lastname: Ward
authors.forename: Bernd J
authors.initials: BJ
authors.lastname: Wintersperger
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Crean
authors.forename: Heather
authors.initials: H
authors.lastname: Ross
authors.forename: Elsie T
authors.initials: ET
authors.lastname: Nguyen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000740:Anemia / Q000097:blood / Q000150:complications / Q000628:therapy*; D001803:Blood Transfusion; D005260:Female; D006801:Humans; D007501:Iron / Q000378:metabolism*; D007502:Iron Chelating Agents / Q000627:therapeutic use*; D019190:Iron Overload / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors; D065227:Transfusion Reaction; D016896:Treatment Outcome; D054088:Ventricular Septum / Q000187:drug effects / Q000378:metabolism; D055815:Young Adult
chemical_list: D007502:Iron Chelating Agents; D007501:Iron