Electronic Posters: Cardiovascular

Myocardial Visibility: Experimental Models

Hall B Monday 14:00-16:00 Computer 33

14:00 3632. Imaging of Inflammation Using VSOP and T2* Mapping in a Mouse Model of Myocardial Infarction

Andrea Protti¹, Alexander Sirker¹, Xuebin Dong¹, Marcelo Andia², Ajay M. Shah¹, Rene Botnar<sup>2

1</sup>Cardiovascular Division, King’s College London BHF Centre of Excellence, London, United Kingdom; ²Division of Imaging Sciences, King’s College London BHF Centre of Excellence, London, United Kingdom

In this work, we sought to investigate the merits of a very small superparamagnetic iron oxide particle (VSOP) for direct imaging of inflammation in a mouse model of MI and to quantify T2* using multi echo gradient echo images. The combined use of a very small iron-oxide particle, VSOP, and the use of short to long TE acquisition to generate T2* mapping allowed the quantitative assessment of VSOP uptake in the infarct zone.

14:30 3633. Studying Indirect Ca²⁺ Alterations Following Myocardial Infarction in a Murine Model Using T₁-Mapping Manganese-Enhanced MRI

Benjamin Waghorn^1,2, Jimei Liu¹, Nathan Yanasak¹, Tom C.-C. Hu<sup>1,2

1</sup>Department of Radiology, Medical College of Georgia, Augusta, GA, United States; ²Nuclear and Radiological Engineering and Medical Physics Programs, Georgia Institute of Technology, Atlanta, GA, United States

Intracellular calcium (Ca²⁺) overloading that occurs during myocardial ischemia-reperfusion is known to exacerbate injuries. This study demonstrates the use of cardiac T₁-mapping manganese-enhanced MRI for identifying and quantifying regional differences in tissue Mn²⁺, and therfore inferred Ca²⁺, handling that occur after a myocardial infarction (MI) in the murine model. Regional alterations in Mn²⁺ efflux were detected, suggesting changes in NCX activity and altered Mn²⁺ content in ischemic tissue, consistent with changes in Ca²⁺ handling post-MI. This technique could potentially be developed to provide and indirect in vivo assessment of Ca²⁺ handling alterations.

15:00 3634. MR Tagging on Healthy and MI Mice Model, an EF Vs Strain Study

Andrea Protti¹, Alexander Sirker¹, Ajay M. Shah¹, Rene Botnar<sup>2

1</sup>Cardiovascular Division, King’s College London BHF Centre of Excellence, London, United Kingdom; ²Division of Imaging Sciences, King’s College London BHF Centre of Excellence, London, United Kingdom

In this study we sought to investigate radial and circumferential strain in a mouse model of myocardial infarction (MI) 3 weeks post left anterior diagonal (LAD) coronary artery ligation and healthy control mice using 2D SPAMM technique. Strain was correlated with ejection fraction (EF) and left ventricular (LV) infarct size. MR tagging analysis provided important information on LV regional contraction and allowed assessment of wall motion alterations in MI mice.

15:30 3635. From Men to Mice: Theoretical Considerations for Edema Imaging at Ultra-High Magnetic Fields

Jurgen E. Schneider¹, Steffen Bohl¹, Erica Dall'Armellina¹, Stefan K. Piechnik¹, Matthew D. Robson¹, Stefan Neubauer<sup>1

1</sup>Cardiovascular Medicine, University of Oxford, Oxford, Oxon, United Kingdom

T2-weighted magnetic resonance imaging (T2w-MRI) has been shown to visualize and to quantify edema in the acutely infarcted myocardium of humans and animal models. Based on relaxation time measurements, we quantitatively demonstrate that the achievable T2-contrast between normal and ischemia-reperfusion injured myocardium in mice at 9.4T is only 60% of the contrast in patients with acute myocardial infarction undergoing CMR at 3T.