Electronic Posters: Cardiovascular

Wednesday 13:30-15:30 Computer 31

13:30 3608. Improved Myocardial Mechanics as Assessed by MRI Generated Pressure-Volume Loops Following AAV6-Mediated βARKct Gene Delivery.

James J. Pilla¹, Jabaris D. Swain, Michael G. Katz, Anthony Fargnoli, Marina Sumaroka, Catherine Tomasulo, Mihail Petrov, Rose Nolen-Walston, JanLee Jensen, Hansell Stedman, Walter J. Koch², Joseph Rabinowitz², Charles R. Bridges

¹University of Pennsylvania, Philadelphia, PA, United States; ²Thomas Jefferson University

Genetic modulation of ventricular function and remodeling may offer a novel therapeutic strategy for patients with acute ischemic left ventricular (LV) dysfunction. We hypothesize that âARKct gene therapy will amplify the cardiac response to a beta-adrenergic agonist resulting in improved function and efficiency as measured by MRI. MRI generated PV loops demonstrated that âARKct expression improves global LV systolic performance and efficiency relative to controls. These results in a normal ovine subject, using a novel, cardiac-specific gene delivery platform (MCARDTM) are predictive of long term efficacy in a clinically relevant large animal HF model.

14:00 3609. Comparison of Magnetic Resonance Imaging and Doppler Echocardiography for the Evaluation of Diastolic Function in Patients with Hypertrophic Cardiomyopathy

Yeon Hyeon Choe¹, Eun Young Kim<sup>2

1</sup>Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea, Republic of; ²Radiology, Samsung Medical Center, Seoul, Korea, Republic of

Diastolic function parameters (mitral inflow velocities, deceleration time, E/A ratio) using phase contrast MRI showed good correlation with that of echocardiography in patients with hypertrophic cardiomyopathy. Analysis of pulmonary vein flow velocity was feasible on MRI and give additional information on diastolic function analysis.

14:30 3610. Evaluation of Patients with Systemic Sclerosis Prior to Hematopoietic Stem-Cell Transplantation Using Cardiac Magnetic Resonance Imaging

Amir H. Davarpanah¹, Aya Kino¹, Kirsi Taimen¹, Philip Hodnet¹, Cormac Farrelly¹, Jeremy Collins¹, Sanjiv Shah², Karin Dill¹, Richard Burt³, James Carr<sup>1

1</sup>Department of Radiology, Cardiovascular Imaging, Northwestern University, chicago, IL, United States; ²Department of Cardiology, Northwestern University, chicago, IL, United States; ³Department of Immunotherapy, Northwestern University, chicago, IL, United States

Using time to peak systole (TPS) from volumetric assessment of right ventricle, may have an important role in detecting both the presence and severity of pulmonary hypertension (PH); It may apply to patients with systemic sclerosis overall, in whom early detection of PH is of significant clinical importance.

15:00 3611. An Optimal Physiologic Model for Study of Murine Cardiac Function Under Inhalational Anesthesia

Christakis Constantinides¹, Richard Mean¹, Laurence W. Hedlund<sup>2

1</sup>Mechanical and Manufacturing Engineering, University of Cyprus, Nicosia, Cyprus; ²Radiology, Duke University Medical Center, Durham, NC, United States

While cardiac mechanical functional studies initially focused on large mammals and the human, the mouse emerged as the preferred animal species for research in recent years. Albeit evidence supports that bioenergetically and hemodynamically the mouse scales linearly with larger mammals and humans, important physiological questions still remain for the appropriateness of this model for extrapolation of conclusions to man. Since the complete characterization of the mouse and human genomes in 2002 and 2003 respectively, there has been a plethora of transgenic mouse studies targeting the cardiovascular system. Equally important were non-invasive imaging studies of such animals for phenotypic and genotypic screening, often conducted under inhalational anesthesia. Anesthetics, however, are known to cause severe cardio-depression with adverse physiological effects on hormonal release, centrally to the heart and peripherally to the vasculature, at the cellular level, affecting calcium entry through L-type Ca2+ channels, the calcium binding sensitivity of the contractile proteins to calcium, and on conduction and excitability. The objective of this study was to determine the isoflurane dose in normal mice for optimal physiological status (respiration, cardiac function, and metabolism) for a period of 1-2 hours post-induction, facilitating migration of such work to the non-invasive imaging platform of MRI, with tremendous potential for future basic science towards the phenotypic screening of transgenic mice and translational research.