Electronic Posters: Cardiovascular

Wednesday 13:30-15:30 Computer 34

13:30 3656. Highly Accelerated Single Breath-Hold Myocardial T₂^* Mapping Using Susceptibility Weighted Fast Spin-Echo Imaging

Fabian Hezel¹, Gabriele Krombach², Sebastian Kozerke³, Thoralf Niendorf<sup>1,4

1</sup>Berlin Ultrahigh Field Facility, Max-Delbrueck Center for Molecular Medicine, Berlin, Germany; ²Department of Diagnostic Radiology, University Hospital, RWTH Aachen, Aachen, Germany; ³Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland; ⁴Experimental and Clinical Research Center (ECRC), Charité Campus Buch, Humboldt-University, Berlin, Germany

Myocardial T2* mapping is proven value for the assessment of myocardial iron content and tissue oxygenation. This study examines the feasibility of highly accelerated fast-spin echo based T2* mapping. Acceleration is accomplished by (i) inner volume imaging, (ii) regional saturation slab based blood suppression,(iii) partial Fourier and (iv) k-t BLAST. A four-fold acceleration is feasible without compromising image quality and the accuracy of calculated T2* values.

14:00 3657. Contrast Optimization for LGE Imaging of Left Atrium

Sathya Vijayakumar¹, Eugene G. Kholmovski¹, Nassir F. Marrouche<sup>2

1</sup>UCAIR, Department of Radiology, University of Utah, Salt Lake City, UT, United States; ²Department of Cardiology, University of Utah, Salt Lake City, UT, United States

While imaging the left atrial wall to assess procedure outcome of RF ablation therapy in the heart, it is necessary to have optimal contrast between scar and blood and scar and normal myocardium. In this work, we present a technique to get optimal contrast between scar and both blood and myocardium using phase sensitive reconstruction and an appropriate choice of inversion time TI.

14:30 3658. Reducing Motion Sensitivity in Free Breathing DWI of the Heart with Localized Principal Component Analysis

Stanislas Rapacchi¹, Pierre Croisille, ^1,2, Vinay Pai³, Denis Grenier¹, Magalie Viallon⁴, Peter Kellman³, Nathan Mewton, ^1,2, Han Wen<sup>3

1</sup>CREATIS, Université Lyon 1, INSA Lyon, Villeurbanne, France; ²Hopital Cardiologique et Pneumologique L. Pradel, Lyon, France, France; ³LCE/NHLBI/NIH, United States; ⁴Hopital Cantonal Universitaire de Genève, Switzerland

Free breathing in vivo cardiac Diffusion Weighted Imaging (DWI) is highly sensitive to physiologic motion. To cope with this issue, we designed a DWI protocol which repeats image acquisition multiple times with incremental trigger delays to cover a large time window in diastole. After registration, a localized Principal Component Analysis (PCA) is employed to reduce inter images myocardium deformation, thus improving final image quality. Then temporal Maximal Intensity Projection (tMIP) (3) is used to find the diffusion weighted intensity for each pixel. We present the benefits of our method and preliminary results in healthy and diseased volunteers.

15:00 3659. Delineating Myocardial Edema and Hemorrhage Using T2, T2*, and Diastolic Wall Thickness Post Acute Myocardial Infarction at 2 Early Time Intervals

Mohammad Imran Zia¹, Nilesh R. Ghugre¹, Gideon A. Paul¹, Jeffrey A. Stainsby¹, Venkat Ramanan¹, Kim A. Connelly¹, Graham A. Wright¹, Alexander J. Dick<sup>1

1</sup>Sunnybrook Health Sciences Centre, Toronto, ON, Canada

Our goal was to demonstrate myocardial edema using T2 spiral and diastolic wall thickness (DWT) and myocardial hemorrhage using T2* in patients post acute myocardial infarction (AMI) at 48 hours and 3 weeks. Assessing the presence and evolution of edema and myocardial hemorrhage early post AMI demonstrates distinct patterns. If myocardial hemorrhage is present, then early scans are affected by the competing effects of T2*, counteracting an increased T2 signal. This may be important in accurately quantifying AAR and identifying those patients most likely to suffer deleterious left ventricular remodeling.