Electronic Posters: Cardiovascular

Tuesday 13:30-15:30 Computer 36

13:30 3684. Carotid Plaque Imaging with an Eight-Channel Transmit/Receive RF Array at 7 Tesla: First Results in Patients with Atherosclerosis.

Tobias Breyer^1,2, Oliver Kraff^1,2, Stefan Maderwald^1,2, Andreas Bitz^1,2, Stephan Orzada^1,2, Mark E. Ladd^1,2, Elke R. Gizewski^1,2, Harald H. Quick, <sup>23

1</sup>Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Nordrhein-Westfalen, Germany; ²Erwin L. Hahn Institute for Magnetic Resonance Imaging, University of Duisburg-Essen, Essen, Germany; ³Institute of Medical Physics, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany

Atherosclerosis is one leading cause of morbidity. In this study we implemented and adapted a plaque imaging protocol from 1.5 to 7 Tesla with use of a custom-built eight-channel transmit/receive RF array for the first time in human patients with hemodynamically relevant atherosclerosis. This approach allows for MR angiographic imaging without administration of gadolinium contrast comparable to contrast-enhanced MR angiography at lower field strengths. Plaque imaging at 7 Tesla requires different sequences compared to lower field strengths but allows a qualitatively comparable depiction of different intraplaque components, calcifications, vessel wall thickness and the luminal surface compared to lower field strenghts.

14:00 3685. Targeted Multi-Contrast Vessel Wall Imaging of Bilateral Peripheral Artery Disease

Niranjan Balu¹, Jinnan Wang², Xihai Zhao¹, Thomas Hatsukami¹, Chun Yuan<sup>1

1</sup>University of Washington, Seattle, WA, United States; ²Philips Research North America

Assessment of vessel wall involvement in peripheral arteries and veins can significantly improve the management of peripheral arterial disease (PAD) and deep vein thrombosis (DVT). The diffuse and bilateral disease in PAD requires bilateral large coverage. Assessment of lesion composition additionally requires multi-contrast imaging. However scan times for current black-blood MRI techniques can be prohibitively long. To address this issue we demonstrate a targeted high resolution multi-contrast imaging protocol combining bilateral isotropic large coverage 3D black-blood MRI for screening and optimized high-resolution 2D black-blood MRI. One case of DVT was identified out of six subjects scanned and characterized by multi-contrast imaging within a 30 minute scan time.

14:30 3686. Sex Differences of High-Risk Carotid Atherosclerotic Plaque in Asymptomatic Patients with Varying Levels of Stenosis -In Vivo 3.0T MRI Study

Hideki Ota^1,2, Mathew J. Reeves³, David C. Zhu², Arshad Majid⁴, Alonso Collar⁵, Nikunj Chauhan, Chun Yuan⁶, J.Kevin DeMarco<sup>2

1</sup>Diagnostic Radiology, Tohoku University, Sendai, Miyagi, Japan; ²Radiology, Michigan State University, East Lansing, MI, United States; ³Epidemiology, Michigan State University, East Lansing, MI, United States; ⁴Neurology & Ophthalmology, Michigan State University, East Lansing, MI, United States; ⁵Ingham Cardiothoracic & Vascular Surgeons, Lansing, MI, United States; ⁶Radiology, University of Washington, Seattle, WA, United States

The purpose of this study was to evaluate prevalence of complicated, high-risk carotid plaque characteristics in both men and women with a broad range of carotid artery stenosis. A total of 230 arteries (51% men) in 132 patients having 0-99% carotid stenosis were included for the analysis. After adjusting for baseline demographic characteristics as possible confounders, presence of complicated AHA VI plaque, lipid-rich/necrotic core, intraplaque hemorrhage were significantly more common in men than women. Increasing MRA stenosis was also associated with these high-risk plaque features. The present results indicate that the development of atherosclerosis appears different between men and women.

15:00 3687. In Vivo Detection of Vulnerable Atherosclerotic Plaque by Magnetic Resonance Imaging

alkystis phinikaridou¹, Frederick L. Ruberg, Hallock J. Kevin, Ye Qiao², Ning Hua, Jason Viereck, James A. Hamilton

¹physiology and biophysics, boston university, boston, ma, United States; ²Johns Hopkins

We used a rabbit model of controlled atherothrombosis to test whether in vivo MRI can distinguish between plaques that disrupt after pharmacological triggering (vulnerable) and those that do not (stable). In vivo MRI revealed that stable and vulnerable plaques had similar percent of stenosis, but vulnerable plaques more frequently showed: (1) positive remodeling, in which the plaque remains hidden within the vessel wall; and (2) enhanced gadolinium uptake associated with histological features of neovascularization, inflammation, and necrosis. These findings suggest that in vivo MRI may be used for localization of plaques that are prone to disruption prior to acute events.