Electronic Posters: Cardiovascular

Wednesday 13:30-15:30 Computer 33

13:30 3640. Triethylenetetramine Treatment in Diabetic Heart Failure: An Animal Trial

Jun Lu^1,2, Beau Pontre³, Stephen Pickup⁴, Bernard SY Choong¹, Mingming Li¹, Hong Xu⁵, Anthony RJ Phillips¹, Garth JS Cooper⁶, Alistair A. Young<sup>7

1</sup>School of Biological Sciences, University of Auckland, Auckland, New Zealand; ²NCIECP, Auckland University of Technology, Auckland, New Zealand; ³Centre for Advance MRI, University of Auckland, Auckland, New Zealand; ⁴Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States; ⁵Chemistry & Chemical Engineering, Shenzhen University, Shenzhen, Guangdong, China; ⁶Department of Pharmacology, Oxford University, Oxford, United Kingdom; ⁷Department of Physiology, University of Auckland, Auckland, New Zealand

End stage diabetes is often associated with heart failure, which is the leading cause of death. We are the first to investigate the heart function in STZ-induced diabetic rats longitudinally with and without triethylenetetramine (TETA) treatment using High Field MRI. Gradient echo cine method was used to determine cardiac function. We found that the cardiac ejection fraction decreased with prolonged diabetic status and oral TETA treatment improves ejection fraction in diabetic rats. The results suggest that TETA treatment is beneficial to diabetic heart failure and warrant further clinical investigation.

14:00 3641. Manganese-Enhanced MRI Combined with Delayed Enhancement MRI Detects Injured Border Zone Myocardium in a Pig Ischemia-Reperfusion Model

Rajesh Dash¹, Jaehoon Chung¹, Yuka Matsuura¹, Fumiaki Ikeno¹, Jennifer Lyons¹, Tomohiko Teramoto¹, Alan C.Y. Yeung¹, Michael V. McConnell^1,2, Todd J. Brinton¹, Phillip Harnish³, Phillip C. Yang<sup>1

1</sup>Division of Cardiovascular Medicine, Stanford University Medical Center, Stanford, CA, United States; ²Department of Electrical Engineering, Stanford University , Stanford, CA, United States; ³Eagle Vision Pharmaceutical Corporation, Exton, PA, United States

Manganese-enhanced MRI (MEMRI) detects Mn²⁺ uptake into viable cells, a distinct mechanism from gadolinium delayed enhancement MRI (DE-MRI). We tested whether combined DE-MRI plus MEMRI would delineate peri-infarct border zone injury in a pig ischemia-reperfusion (IR). Pigs were imaged by cardiac MRI 3 weeks post-IR. 3D DE-MRI scar volume correlated with histopathologic scar volume, but MEMRI scar volume was significantly smaller than DE-MRI scar volume. The border zones of DE-MRI scar, which were also positive by MEMRI, showed decreased SNR compared to remote zone MEMRI SNR. Combined MEMRI and DE-MRI may identify injured border zone myocardium in ischemic cardiomyopathy.

14:30 3642. Diffusion Tensor Shape Measurements of Infarcted Myocardium in Porcine Models Using Three Phase Geometric Analysis

Yin Wu^1,2, Ed Xuekui Wu<sup>2,3

1</sup>Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Shenzhen, Guangdong, China; ²Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Pokfulam, Hong Kong; ³Dept. of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam, Hong Kong

Previous DTI studies on infarcted LV myocardium structure usually investigated diffusivity and diffusion anisotropy. In current study, diffusion tensor shape with a combination of linear, planar and spherical measures are examined and illustrated on a three-phase space in porcine models. Results show that the measurements of tensor shape have significant alteration in infarcted myocardium and are more sensitive to detect subtle change of diffusion properties than conventionally used parameters. Infarct location shows no apparent influence on myocardium structural degradation. This study gives insights into myocardium structural alteration and demonstrates potential application of DTI in detecting infarcted heart remodeling.

15:00 3643. Whole Mount Heart Histology: A New Gold Standard for Myocardial Damage Validation in Experimental Cardiac MRI Studies?

Yuesong Yang¹, Kela Liu¹, Dan Wang¹, Mihaela Pop¹, Jay Detsky¹, Yingli Lu¹, Alexander J. Dick¹, Martin J. Yaffe¹, Graham A. Wright<sup>1

1</sup>Imaging Research, Sunnybrook Health Sciences Centre, University Of Toronto, Toronto, Ontario, Canada

Triphenyltetrazolium chloride (TTC) stain is commonly used for the validation of myocardial damage in experimental cardiac MRI studies using various animal species such as mice, dogs and pigs. However, subtle myocardial damage, border zone or infarct heterogeneity associated with myocardial infarction (MI) is difficult to recognize on TTC stains. In this study, we investigated the feasibility of whole-mount heart histology that preserved the 3D morphology with a digital display at the microscopic level as a new alternative in the validation of myocardial damage in a porcine model of MI in experimental cardiac late-enhancement (LE) MRI studies.