Electronic Posters: Cardiovascular

Thursday 13:30-15:30 Computer 33

13:30 3644. Comparison of Scar Morphology by 3D Multi-Contrast Late Enhancement MRI, 3D DW-MRI and Histology in a Pig Model of Chronic Infarct

Mihaela Pop¹, Venkat Ramanan, Yuesong Yang, Nilesh Ghugre, Beiping Qiang, Elliot R. McVeigh², Alexander J. Dick³, Graham A. Wright

¹Medical Biophysics, Sunnybrook Research Institute, University of Toronto, Toronto, ON, Canada; ²Biomedical Engineering, Johns Hopkins University, United States; ³Cardiology, Sunnybrook Research Institute

Accurate assessment of the scar extent and tissue remodeling during healing is very important. To better understand the scar morphology associated with chronic infarct in a porcine model, we have developed and tested (ex vivo) a 3D pulse sequence based on multi-contrast late enhancement (MCLE) and a non-contrast 3D diffusion-weighted DW sequence, and compare the results against histopathology. We have found that 3D MCLE identifies fine heterogeneity of scar, and compares well the classification of pathology to that from apparent diffusion coeficient maps using DW-MRI.

14:00 3645. Respiratory Self-Gated 2D Cine Balanced SSFP Myocardial Edema Imaging: Preliminary Study in Canines

Swati Gupta¹, Xiangzhi Zhou², Xiaoming Bi³, Saurabh Shah³, Sven Zuehlsdorff³, Andrew Larson², Debiao Li², Rohan Dharmakumar<sup>2

1</sup>Department of Biomedical Engineeering, Northwestern University, Chicago, IL, United States; ²Department of Radiology, Northwestern University, Chicago, IL, United States; ³Siemens Medical Solutions, Chicago, IL, United States

Myocardial edema imaging with bSSFP approaches have been recently demonstrated. In this work, we investigated the utility of respiratory self-gated (RSG) 2D cine bSSFP for acquiring free-breathing myocardial edema images using a canine model subjected to ischemia-reperfusion injury. Early results show that RSG bSSFP imaging is capable of generating edema contrast similar to breath-held bSSFP imaging.

14:30 3646. Repair of Cardiac Damage Using Intrapericardial Drug Delivery by Means of MR-Trackable Alginate Beads

Yamin Yang¹, Marco L.H. Gruwel², Patricia Gervai³, Jiankang Sun³, Olga Jilkina¹, Eugene Gussakovsky¹, Valery Kupriyanov<sup>1

1</sup>Cardiac, NRC-CNRC Institute for Biodiagnostics, Winnipeg, MB, Canada; ²MRTechnology, NRC-CNRC Institute for Biodiagnostics, Winnipeg, MB, Canada; ³MRRD, NRC-CNRC Institute for Biodiagnostics, Winnipeg, MB, Canada

Re-establishment of a vascular network is an important step in the repair of damaged myocardium. For this purpose vascular growth factors were applied at the site of injury. To prolong action of these peptides, growth factors were incorporated in alginate beads. However, visualization of the beads is not an easy task.

15:00 3647. Comprehensive and Serial Evaluation of Myocardial Structure, Function and Perfusion in Reperfused Infarct

Maythem Saeed¹, Alastair J. Martin¹, Loi Do¹, David Saloner¹, Mark Wilson<sup>1

1</sup>Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, Ca, United States

MR imaging was used to 1) assess the changes in LV volumes, ejection fraction, LV mass, regional wall thickness, and 3D wall strain as well as myocardial structure, edema, microvascular obstruction and intramyocardial haemorrhage in reperfused infarct in a single imaging session, to ensure image co-registration and 2) compare LV changes over 10 weeks. MR imaging provides comprehensive and serial characterization of evolved infarct. Myocardial edema, microvascular obstruction and hemorrhage are transient features of reperfusion injury. Based on the MR pulse sequences used it appears five weeks is enough time to arrest fibrosis, but not LV dilation, in reperfused infarct.