title: The correlation of 3D DT-MRI fiber disruption with structural and mechanical degeneration in porcine myocardium.
abstract: Evaluation of structural parameters following a myocardial infarction (MI) is important to assess left ventricular function and remodeling. In this study, we assessed the capability of 3D diffusion tensor magnetic resonance imaging (DT-MRI) to assess tissue degeneration shortly after an MI using a porcine model of infarction. Two days after an induced infarction, hearts were explanted and immediately scanned by a 3T MRI scanner with a diffusion tensor imaging protocol. 3D fiber tracks and clustering models were generated from the diffusion-weighted imaging data. We found in a normal explanted heart that DT-MRI fibers showed a multilayered helical structure, with fiber architecture and fiber density reflecting the integrity of muscle fibers. For infarcted heart explants, we observed either a lack of fibers or disruption of fibers in the infarcted regions. Contours of the disrupted DT-MRI fibers were found to be consistent with the infarcted regions. Both histological and mechanical analysis of the infarcted hearts suggested DT-MRI fiber disruption correlated with altered microstructure and tissue mechanics. The ability of 3D DT-MRI to accurately distinguish viable myocardium from dead myocardium only 2 days post infarct without the use of radioisotopes or ionotropic agents makes it a promising approach to evaluate cardiac damage early post-MI.
authors.affiliation: Department of Computer Science and Engineering, Mississippi State University, Mississippi State, MS, USA.
authors.forename: Song
authors.initials: S
authors.lastname: Zhang
authors.forename: J Allen
authors.initials: JA
authors.lastname: Crow
authors.forename: Xiaoyong
authors.initials: X
authors.lastname: Yang
authors.forename: Joseph
authors.initials: J
authors.lastname: Chen
authors.forename: Ali
authors.initials: A
authors.lastname: Borazjani
authors.forename: Katie B
authors.initials: KB
authors.lastname: Mullins
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Robert C
authors.initials: RC
authors.lastname: Cooper
authors.forename: Ronald M
authors.initials: RM
authors.lastname: McLaughlin
authors.forename: Jun
authors.initials: J
authors.lastname: Liao
mesh_terms: D000818:Animals; D056324:Diffusion Tensor Imaging / Q000379:methods*; D004195:Disease Models, Animal; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D009206:Myocardium; D011859:Radiography; D013552:Swine