Electronic poster


Tuesday 13:30-15:30 Computer 29



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Tuesday 13:30-15:30 Computer 29

13:30 3572. Measuring the Myocardial Angular Information Through the Radial Tagging

Abbas Nasiraei Moghaddam1, J. Paul Finn1

1Radiology, UCLA, Los Angeles, CA, United States

The angular information of the left ventricle, including the twist, shear and circumferential strain, are of fundamental importance to quantify the regional or global myocardial function . Radial tagging facilitates the measurement of this information . In particular when the density of radial taglines are sufficiently high, it was theoretically shown that the circumferential strain can be measured directly from the K-Space data . In this study we present the application of the circumferential encoding method on the actual cardiac MR images which are tightly tagged in the radial direction using our newly developed sequence. We also show the transmural differences in rotational motion of the left ventricle using these images.



14:00 3573. High Spatio-Temporal Fidelity Nongated Cardiac MRI with a 3 Second Patient-Adaptive Scan

Behzad Sharif1, John Andrew Derbyshire2, Yoram Bresler1

1Electrical and Computer Engineering, Coordinated Science Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, United States; 2Translational Medicine Branch, NHLBI, National Institutes of Health, Bethesda, MD, United States

Patient-Adaptive Reconstruction and Acquisition Dynamic Imaging with Sensitivity Encoding (PARADISE), is a highly accelerated non-gated dynamic imaging scheme that enables artifact-free imaging while providing performance guarantees on achievable SNR and spatio-temporal resolution. In addition to parallel imaging, the method gains acceleration from a sparse physiologically-driven spectral support model (in x-y-f space); hence it is doubly accelerated and adaptive. In this work, we present a modification of the PARADISE method that enables high spatio-temporal fidelity nongated 2D cine imaging with short scan times (3 seconds per slice). The method uses prospective adjustments to the x-y-f-space support to accommodate short scan times.



14:30 3574. Prolonged Right Ventricular Post-Systolic Isovolumic Period in Pulmonary Arterial Hypertension: A Reflection of Diastolic Dysfunction?

Gert Jan Mauritz1, J. Tim Marcus1, Nico Westerhof1, Pieter E. Postmus1, Anton Vonk Noordegraaf1

1VU University Medical Center, Amsterdam, Netherlands

In PAH a prolonged time interval between pulmonary valve closure and tricuspid valve opening is observed. This period is assumed to measure a prolonged right ventricular (RV) relaxation, and to reflect diastolic dysfunction. In this study it was shown that this period is the consequence of a prolonged contraction of the RV free wall which continues after pulmonary valve closure causing a post-systolic contraction. In contrast the RV isovolumic relaxation period is not increased. Therefore, in clinical practice the isovolumic period between pulmonary valve closure and tricuspid valve opening is not a real measure of diastolic dysfunction in PAH patients.



15:00 3575. The Impact of Myosin Heavy Chain Isoforms on Contractile Behavior of the Heart

Yong Chen1,2, Julian E. Stelzer3, Xin Yu1,2

1Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States; 2Case Center for Imaging Research, Case Western Reserve University, Cleveland, OH, United States; 3Department of Physiology and Biophysics, Case Western Reserve University

In the present study, we evaluated the impact of shift in myosin heavy chain (MHC) isoforms on in vivo ventricular function in thyroid-deficient rats. Our results show that increased expression of β-MHC not only reduced the magnitude of peak systolic strain and torsion, but also altered the timing when the myocardium reached peak systole, leading to deteriorated cardiac function in hypothyroid rat hearts.



Wednesday 13:30-15:30 Computer 29

13:30 3576. Increased Left Ventricular Torsion in Hypertrophic Cardiomyopathy Mutation Carriers with Normal Wall Thickness

Iris Rüssel1, Wessel Brouwer1, Tjeerd Germans1, Paul Knaapen1, J Tim Marcus1, Jolanda van der Velden1, Marco Götte1, Albert van Rossum1

1VU University Medical Center, Amsterdam, Netherlands

Hypertrophic cardiomyopathy (HCM) is caused by mutations in mainly sarcomeric genes. Increased left ventricular (LV) torsion has been observed in patients with manifest hypertrophy, but abnormalities in myocardial contractility might already be present in HCM mutation carriers with normal wall thickness. Therefore, LV torsion and endocardial circumferential strain were studied in HCM mutation carriers using MRI tagging. Increased LV torsion and torsion to endocardial circumferential strain-ratio were found in carriers with respect to controls. The observed difference might be due to HCM-related endocardial myocardial dysfunction.



14:00 3577. Reconstruction of Line Tagged Cardiac Images by Compressed Sensing Algorithm Using Contourlet Transform from Appropriate K-Space Sampling

Sung-Min Gho1, Narae Choi1, Dong-Hyun Kim1,2

1Electrical and Electronic Engineering, Yonsei University, Shinchon-Dong, Seoul, Korea, Republic of; 2Radiology, Yonsei University, Shinchon-Dong, Seoul, Korea, Republic of

RF tagging in cardiac imaging can be used to analyze the heart wall motion. There is always a push towards higher spatial and/or temporal resolution to enable more accurate quantification. This work is on combining line tagged cardiac imaging with the compressed sensing (CS) algorithm and exploiting the distinct k-space feature of tagged images.



14:30 3578. Characterization of Vortex Flow in the Left Ventricle by Phase Contrast Magnetic Resonance Imaging

Samuel Ting1, Paaladinesh Thavendiranathan1, Helene Houle2, Gianni Pedrizzetti3, Subha V. Raman1, Mani Vannan1, Orlando Simonetti1

1The Ohio State University, Columbus, OH, United States; 2Siemens Medical Solutions, Mountain View, CA, United States; 3University of Trieste, Trieste, Italy

Characterization of vortex formation and flow within the heart may be used as tool for diagnosing and understanding pathophysiological conditions of the heart. We present preliminary results demonstrating that phase contrast magnetic resonance imaging may be used to quantitatively evaluate and characterize formation of vortices within blood flow in the left ventricle of the heart.



15:00 3579. Quantitative Assessment of Atrioventricular Plane Displacement in Normals and Diastolic Heart Failure-A Cine MRI Study.

Reena Anand1, Sohae Chung1, Sharath Bhagavatula, Leon Axel1

1Radiology, NYU Langone Medical Center, New York, NY, United States

In conventional cine MRI, it is observed that the atrioventricular (AV) plane of the heart descends towards the apex during systole and moves back towards the atrium during the diastole. The displacement of the AV plane through the cardiac cycle is an expression of the systolic and diastolic performance of the heart, so that it can be used to detect early diastolic dysfunction. In this study, we have investigated the potential of MRI measurement of left AV plane displacement as a means to assess diastolic dysfunction.



Thursday 13:30-15:30 Computer 29

13:30 3580. Combination of Through-Plane Tissue Phase Mapping and SPAMM for 3D Cardiac Motion Assessment

Anja Lutz1, Axel Bornstedt1, Robert Manzke2, Gerd Ulrich Nienhaus3, Volker Rasche1

1University Hospital of Ulm, Ulm, BW, Germany; 2Philips Research Europe, Hamburg; 3Institute of Technology, University of Karlsruhe, Germany

Cardiac motion assessment can be performed by tagged imaging combined with HARP analysis and with tissue phase mapping (TPM). The tagging approach enables fast assessment of the in-plane motion component, where TPM can be applied for full assessment of the motion vector in 3D but requires at least fourfold measurement time. In this contribution tagging is combined with TPM for 3D + time motion assessment. There is no information loss of the through plane motion, when tag lines are applied. The combination can be used to reduce imaging time for motion encoding in 3D.



14:00 3581. MRI Compatible Treadmill

Eric L. Foster1, Mihaela Jekic1,2, Jacob A. Bender1,2, John W. Arnold3, Subha V. Raman1,4, Orlando P. Simonetti1,5

1Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, United States; 2Biomedical Engineering, The Ohio State University; 3Agricultural Technical Institute, The Ohio State University; 4Internal Medicine, The Ohio State University; 5Internal Medicine and Radiology, The Ohio State University

Treadmill exercise testing in conjunction with MRI may offer improved diagnosis of heart disease compared to current modalities; however, traditional treadmills can not operate safely within the MR environment. An MR compatible treadmill was developed using hydraulic drive and elevation systems and fiber-optic data transmission, allowing the treadmill to be positioned immediately adjacent to the MR examination table. The treadmill successfully passed MR safety and compatibility tests. Six healthy volunteers were exercised to peak cardiovascular stress and transferred to the MR table. Real time cine imaging was completed within 38±6.4 s, meeting the AHA guideline of imaging within 60 s.



14:30 3582. Early Diastolic Strain-Velocity Temporal Relationship Assessment Using SPAMM-PAVE

Ziheng Zhang1, Donald P. Dione1, Peter B. Brown1, Erik M. Shapiro1, Chengqing Wu2, Robert Todd Constable1, Albert J. Sinusas1, Smita Sampath1

1Yale University School of Medicine, New Haven, CT, United States; 2Yale University School of Public Health, New Haven, CT, United States

A novel MR imaging technique, spatial modulation of magnetization with polarity alternated velocity encoding (SPAMM-PAVE), is presented to investigate the left ventricular early diastolic strain-velocity relationships. This technique provides simultaneous measurements of 1-D myocardial displacement and chamber blood velocity with a high temporal resolution of 14 ms, sensitive to early diastolic events undetectable by current state-of-the-art methods. The reliability of the measurement is demonstrated by an intra-subject study of a normal volunteer. The interplay of regional volumetric changes in the left ventricle in response to filling patterns is investigated through comparing the regional strain and blood inflow velocity curves in 8 normal volunteer studies.



15:00 3583. 4CH TX/RX Surface Coil for 7T: Design, Optimization and Application for Cardiac Function Imaging

Matthias Alexander Dieringer1,2, Wolfgang Renz, 1,3, Tomasz Lindel, 1,4, Frank Seifert, 1,4, Tobias Frauenrath1, Helmar Waiczies, 1,4, Florian von Knobelsdorff-Brenkhoff5, Davide Santoro1, Werner Hoffmann4, Bernd Ittermann, 1,4, Jeanette Schulz-Menger2,5, Thoralf Niendorf1,2

1Berlin Ultrahigh Field Facility, Max-Delbrueck-Center for Molecular Medicine, Berlin, Germany; 2Experimental and Clinical Research Center (ECRC), Charité Campus Buch, Humboldt-University, Berlin, Germany; 3Siemens Healthcare, Erlangen, Germany; 4Physikalisch-Technische Bundesanstalt (PTB), Berlin, Germany; 5CMR-Unit Charité Campus Buch, Berlin, Germany

Practical impediments of ultra high field cardiovascular MR (CVMR) can be catalogued in exacerbated magnetic field and radio frequency (RF) inhomogeneities, susceptibility and off-resonance effects, conductive and dielectric effects in tissue, and RF power deposition constraints, which all bear the potential to spoil the benefit of CVMR at 7T. Therefore, a four element cardiac transceive surface coil array was developed. Cardiac imaging provided clinically acceptable signal homogeneity with an excellent blood myocardium contrast. Subtle anatomic structures, such as pericardium, mitral and tricuspid valves and their apparatus, papillary muscles, and trabecles were accurately delineated.



Myocardial Function: Experimental & Human Studies II

Hall B Monday 14:00-16:00 Computer 30

14:00 3584. Left Ventricular Dyssynchrony: Effect of Age, Ejection Fraction, Mass and Cardiovascular Disease

Daniela Foell1, Bernd Jung2, Elfriede Schilli3, Felix Staehle2, Christoph Bode3, Michael Markl2

1Cardiology , University Hospital , Freiburg, Germany; 2Diagnostic Radiology, Medical Physics, University Hospital, Freiburg, Germany; 3Cardiology, University Hospital, Freiburg, Germany

MR tissue phase mapping (TPM) was employed to study the relationships of age, heart rate, left ventricular (LV) ejection fraction (EF), and LV-mass with myocardial dyssynchrony among 95 subjects with normal and pathological cardiac function. Compared to age-matched controls significantly (p<0.01) enhanced myocardial dyssynchrony was found in patients with hypertensive heart disease (n=18) and dilated cardiomyopathy (n=12) with most prominent changes if left bundle branch block was present (n=7). Multiple regressions revealed significant relationships of dyssynchrony with LV-EF, LV-mass, and age. As sensitive markers for LV dysfunction, both radial systolic and long-axis diastolic dyssynchrony were superior to systolic long-axis dyssynchrony.



14:30 3585. MR Assessment of Left Ventricular Strain After Repair of Tetralogy of Fallot

Karen G. Ordovas1, Marcus Carlsson2, Elyse Foster3, Alison Meadows4, Alastair Martin4, Michael Hope4, Loi Do4, Charles Higgins4, Maythem Saeed4

1Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States; 2Clinical Physiology, Lund University, Lund, Sweden; 3Cariology, UCSF, San Francisco, CA, United States; 4Radiology and Biomedical Imaging, UCSF, San Francisco, CA, United States

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15:00 3586. Assessment of Cardiac Function and Infarct Size Following Myocardial Infarction in Mitochondrial Cyclophilin-D Knockout Mice



Anthony N. Price1, Shiang Y. Lim2, Johannes Riegler1, Derek M. Yellon2, Derek J. Hausenloy2, Mark F. Lythgoe1

1Centre for Advanced Biomedical Imaging, Department of Medicine and UCL Institute of Child Health, University College London, London, United Kingdom; 2The Hatter Cardiovascular Institute, University College London Hospital and Medical School, London, United Kingdom

Coronary heart disease (CHD) remains one of the leading causes of morbidity and mortality worldwide. A principal symptom of CHD is myocardial infarction (MI), which leads to a complex process of ventricular remodelling and ultimately heart failure. Novel treatment strategies which are capable of limiting myocardial infarct size, preventing LV remodelling and preserving cardiac function are needed to improve clinical outcomes. The inhibition of mitochondrial cyclophilin-D (CypD), has been reported to reduce infarct size in pre-clinical studies. Here we present the first MRI assessment of cardiac function and infarct size in CypD-/- mice at 48 hours following myocardial infarction.



15:30 3587. Healthy Ageing in Females Is Associated with Altered Cardiac Energetics Related to Both Systolic and Diastolic Function: A Comparison of MRS, Cardiac Tagging and Cine Imaging

Kieren Grant Hollingsworth1, David Emerys Jones2, Julia Lindsay Newton3, Bernard D. Keavney4, Guy A. MacGowan5, Andrew Mark Blamire1

1Newcastle Magnetic Resonance Centre, Newcastle University, Newcastle upon Tyne, Tyne and Wear, United Kingdom; 2Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, Tyne and Wear, United Kingdom; 3Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne, Tyne and Wear, United Kingdom; 4Institute of Human Genetics, Newcastle University, Newcastle upon Tyne, Tyne and Wear, United Kingdom; 5Cardiology, Freeman Hospital, Newcastle upon Tyne, Tyne and Wear, United Kingdom

It is unclear whether there are relationships between cardiac energetics and age-related decline of systolic and diastolic function. 25 healthy females with no previous history of cardiac disease were recruited, covering the age range 18-65. Phosphorus spectroscopy, cine imaging and cardiac tagging were carried out. PCr/ATP ratio was found to decline significantly with age, most strongly in the over 60 group. E/A ratio, peak circumferential strain and torsion recoil rates declined with age, with the first two significantly associated with the PCr/ATP ratio. This suggests that both systolic and diastolic function are associated with energetic changes in ageing.



Tuesday 13:30-15:30 Computer 30

13:30 3588. γ-Sarcoglycan Deficiency Reduces Cardiac Function and T2 in Old Mice

Sean Charles Forbes1, Sean Germain2, Nathan Bryant3, Glenn A. Walter3

1Department of Physical Therapy, University of Florida, Gainesville, FL, United States; 2Department of Pediatrics, University of Florida, United States; 3Department of Physiology and Functional Genomics, University of Florida, United States

Limb Girdle muscular dystrophy Type 2C is characterized by a deficiency in γ-sarcoglycan, a protein associated with the dystrophin-glycoprotein complex on the cell membrane. In this study, the effects of a lack of γ-sarcoglycan (Sgsg-/-) and dystrophin (mdx) on cardiac function and myocardium T2 in old mice were examined. The findings indicate that Sgsg-/- and mdx have a reduced left ventricular ejection fraction compared to age-matched controls, with no differences in Sgsg-/- and mdx. Also, a shorter T2 was observed in the myocardium of Sgsg-/- compared to controls, suggesting an increased prevalence of fibrosis in Sgsg-/-.



14:00 3589. Development and Validation of 3 Tesla Functional Cardiac Magnetic Resonance Imaging in Preterm and Term Newborns

Alan Groves1, Gaia Chiesa2, Giuliana Durighel2, Stephen Goldring2, Julie Fitzpatrick2, Sergio Uribe3, Reza Razavi4, Jo Hajnal2, A David Edwards2

1Institute of Clinical Sciences, Imperial College , London, United Kingdom; 2Institute of Clinical Sciences, Imperial College, London, United Kingdom; 3Division of Imaging Sciences, King's College , London, United Kingdom; 4Division of Imaging Sciences, King's College, London, United Kingdom

The ability to reliably monitor and support the circulation in preterm and term newborns may have a key role in optimising outcome in this population. Cardiac magnetic resonance (CMR) imaging has the potential to significantly advance understanding of cardiac function in sick preterm and term infants. In this work we describe optimisation of cine and phase contrast CMR imaging in newborn infants; assess repeatability of CMR methods and compare this to existing echocardiographic methods; and describe preliminary normative values for cardiac output and systemic flow volume in stable preterm and term infants.



14:30 3590. The Effect of K-Space Trajectory on Strain-Encoded Cardiac MRI

Elsayed H. Ibrahim1, Wolfgang Rehwald2, Sven Zuehlsdorff2, Richard D. White1

1University of Florida, College of Medicine, Jacksonville, FL, United States; 2Siemens AG Healthcare Sector, Cardiovscular MR R&D, Chicago, IL, United States

Strain encoding (SENC) is a newly-developed MRI technique for measuring myocardial strain in the through-plane direction. It requires simple post-processing and gives resolution on the pixel level. With conventional SENC sequence, two separate scans are required to obtain the strain images. Such approach increases scan time and could result in image misregistration in post-processing. Non-Cartesian k-space trajectories are becoming more popular because they allow for large undersampling with acceptable image quality. In this work, SENC was combined with radial k-space acquisition using interleaved SENC tunings and radial undersampling. Scan time was reduced to one breath-hold with comparable image quality.



15:00 3591. High Resolution, Functional Real-Time Cardiac MR Imaging Using a Combination of Compressed Sensing and Parallel Imaging

Tobias Wech1, Marcel Gutberlet1, Daniel Stäb1, Dietbert Hahn1, Herbert Köstler1

1Institute of Radiology, University of Wuerzburg, Wuerzburg, Bavaria, Germany

To achieve a sufficient temporal and spatial resolution in functional cardiac MRI, real time acquisition has to be accelerated by a factor of 8 – 10 compared to Fourier MRI. In this work, a combination of compressed sensing and parallel imaging has been implemented, tested in a simulation using undersampled data of a segmented cine acquisition and finally applied to in-vivo data sampled in real time. The reconstructions for the real time acquisition and for the simulated data result in high resolution images with an excellent SNR and do not show any visible artefacts.



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