Kevin Moulin^1,2,3, Pierre Croisille^4,5, Magalie Viallon^4,5, Ilya A Verzhbinsky⁶, Luigi E Perotti⁷, and Daniel B Ennis^1,2,3
1Department of Radiology, Stanford University, Stanford, CA, United States, ²Department of Radiology, Veterans Administration Health Care System, Palo Alto, CA, United States, ³Cardiovascular Institute, Stanford University, Stanford, CA, United States, ⁴University of Lyon, UJM-Saint-Etienne, INSA, CNRS UMR 5520, INSERM U1206, CREATIS, F-42023, Saint-Etienne, France, ⁵Department of Radiology, University Hospital Saint-Etienne, Saint-Etienne, France, ⁶Medical Scientist Training Program, University of California - San Diego, La Jolla, CA, United States, ⁷Department of Mechanical and Aerospace Engineering, University of Central Florida, Orlando, FL, United States

Despite the importance of myofiber strain (E_ff) to overall heart function, it has remained very difficult to measure E_ff in vivo owing to the challenges of measuring both microstructural and functional cardiac data. We propose a new method that integrates cDTI and a volume of short- and long-axis DENSE slices with 2D displacement encoding to enable the measurement of in vivo Eff in humans. The accuracy of the approach for measuring Eff was evaluated in silico. Finally, in vivo E_ff values were measured and reported for thirty (N=30) healthy volunteers for which an average E_ff=-0.14 was found.

Yin Wu¹, Jie Liu¹, Qi Liu², Hui Liu², Jian Xu², Yuanwei Xu³, Yucheng Chen³, Xin Liu¹, and Hairong Zheng^1
1Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China, ²United Imaging Healthcare America, Houston, TX, United States, ³Cardiology Division, West China Hospital, Sichuan University, Chengdu, China

This study aims to investigate the feasibility of creatine (Cr) CEST imaging in assessing cardiac contractile function impairment. Eleven MI pigs underwent cine, Cr CEST and LGE imaging at 3T. Significant reduction of Cr CEST and function indices (i.e., CS, RS, WT and WM) was shown in infarct myocardium compared to that in the remote region. Cardiac function indices were shown to decrease with Cr CEST signal with moderate correlations (P<0.001). The study demonstrated the intrinsic linkage between creatine metabolic and functional changes in MI heart, suggesting the feasibility of Cr CEST in evaluating cardiac dysfunction at the molecular level.

Hsin-Yu Chen¹, Jeremy W. Gordon¹, Nicholas Dwork¹, Brian T. Chung¹, Andrew Riselli², Robert A. Bok¹, James B. Slater¹, M. Roselle Abraham³, Daniel B. Vigneron¹, and Peder E.Z. Larson^1
1Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States, ²School of Pharmacy, University of California, San Francisco, San Francisco, CA, United States, ³Department of Medicine-Cardiology, University of California, San Francisco, San Francisco, CA, United States

This study explored the safety and feasibility to visualize real-time myocardial Krebs cycle energetics in healthy volunteers using hyperpolarized [2-¹³C]pyruvate MR spectroscopy, and to investigate the response to oral glucose challenge. Identified metabolic products included [2-¹³C]lactate, Krebs cycle-related intermediate [5-¹³C]glutamate, and [1-¹³C]acetylcarnitine, a key player in the “carnitine shuttle” of mitochondrial fatty acid oxidation. Upon oral glucose challenge, the levels of all three products increased, illustrating the metabolic flexibility of human heart to switch between fatty acid and carbohydrates.

Aurelien Bustin^1,2,3, Soumaya Sridi², Solenn Toupin⁴, Jerome Yerly^3,5, Davide Piccini^3,6, Ruud B van Heeswijk³, Pierre Jaïs^1,7, Hubert Cochet^1,2, and Matthias Stuber^1,3,5
1IHU LIRYC, Electrophysiology and Heart Modeling Institute, Université de Bordeaux, INSERM, Centre de recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux, France, ²Department of Cardiovascular Imaging, Hôpital Cardiologique du Haut-Lévêque, CHU de Bordeaux, Bordeaux, France, ³Department of Diagnostic and Interventional Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland, ⁴Siemens Healthcare France, Saint-Denis, France, ⁵Center for Biomedical Imaging (CIBM), Lausanne, Switzerland, ⁶Advanced Clinical Imaging Technology, Siemens Healthcare, Lausanne, Switzerland, ⁷Department of Cardiac Electrophysiology, Hôpital Cardiologique du Haut-Lévêque, CHU de Bordeaux, Bordeaux, France

Magnetic resonance T1 rho mapping may detect myocardial injuries without the need for exogenous contrast agents. However, multiple and differently T1 rho weighted co-registered acquisitions are required, and the lack of robust motion correction limits its clinical translation. This study introduces a novel automated model-based non-rigid motion correction technique for myocardial T1 rho mapping that makes use of the known signal model to drive the motion correction process. The performance, efficiency and clinical feasibility of the developed framework was investigated prospectively in a cohort of 30 patients with a broad range of ischemic and non-ischemic cardiomyopathies.

Brendan L Eck¹, Nicole Seiberlich², Scott D Flamm^1,3, Jesse I Hamilton², Mazen Hanna³, Yash Kumar⁴, Abhilash Suresh³, Angel Lawrence^1,3, W. H. Wilson Tang³, and Deborah Kwon^3
1Imaging Institute, Cleveland Clinic, Cleveland, OH, United States, ²Radiology, University of Michigan, Ann Arbor, MI, United States, ³Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, United States, ⁴Case Western Reserve University, Cleveland, OH, United States

Cardiac amyloidosis is an infiltrative cardiomyopathy characterized by the accumulation of misfolded proteins in the myocardium. Elevated myocardial T₁ and T₂ have been reported as a potential biomarker of disease. Cardiac Magnetic Resonance Fingerprinting (cMRF) has the potential to provide improved tissue characterization for cardiac amyloidosis through simultaneous T₁ and T₂ mapping. Furthermore, signal evolutions obtained by cMRF may enable improved tissue characterization. In this preliminary study of cardiac amyloidosis patients, relaxometric quantities and signal evolution data are analyzed. Myocardial T₁ and T₂ were elevated in patients, and linear discriminant analysis of signal evolution data suggests improved discrimination of disease.

Xianglun Mao¹, Fardad M Serry¹, Sen Ma¹, Zhehao Hu^1,2, Alan C Kwan^1,3, Fei Han⁴, Yibin Xie¹, Debiao Li^1,2, and Anthony G Christodoulou^1,2
1Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States, ²Department of Bioengineering, University of California in Los Angeles, Los Angeles, CA, United States, ³Smidt Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States, ⁴Siemens Medical Solutions Inc., Los Angeles, CA, United States

Conventional cardiovascular MR (CMR) exams are relatively inefficient and demanding for patients because 1) they rely on methods that necessitate breath-holding or intermittent pauses (via gating) to compensate for motion, 2) images are acquired as a series of 2D slices often with large gaps. We propose a single 3D free-breathing acquisition without ECG requirements, providing motion resolved, quantitative T1 and T2 cine mapping with whole-ventricle coverage with high resolution and no slice gaps. The 3D Multitasking framework additionally incorporates a B1+ component, critical for accurate T1 measurement at 3T. This technique is preliminarily validated both in phantoms and healthy volunteers.

Carlos Velasco¹, Gastao Cruz¹, René M. Botnar¹, and Claudia Prieto^1
1School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom

Cardiac Magnetic Resonance Fingerprinting (MRF) has shown promising results for myocardial fibrosis and inflammation characterization. In addition, T_1ρ mapping has shown promising results for detection of focal and diffuse myocardial fibrosis without the need of exogenous contrast agents. However, multiparametric T₁, T₂ and T_1ρ mapping requires sequential acquisitions under several breath-holds, that can lead to non-registered maps and bias due to inter-parameter dependencies. In this work we propose a cardiac MRF acquisition scheme for simultaneous quantification of myocardial T₁, T₂ and T_1ρ in a contrast-free single breath-hold MR scan. The proposed approach has been investigated in phantoms and healthy subjects.

Simone Rumac¹, Christopher W. Roy², Jérôme Yerly^2,3, John Heerfordt^2,4, Davide Piccini^2,4, Matthias Stuber^3,5, and Ruud B. van Heeswijk^2
1Department of Radiology, Department of Radiology, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Laus, Lausanne, Switzerland, ²Department of Radiology, Department of Radiology, Lausanne University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland, Lausanne, Switzerland, ³CIBM Center for BioMedical Imaging, Lausanne, Switzerland, Lausanne, Switzerland, ⁴Advanced Clinical Imaging Technology, Siemens Healthcare AG, Lausanne, Switzerland, Lausanne, Switzerland, ⁵Department of Radiology, Department of Radiology, Lausanne University Hospital (CHUV) and University of Lausanne, Lausanne, Switzerland

Cardiac parametric mapping techniques are gaining traction for the clinical routine assessment of various pathologies. Despite the complex 3D patterns of many myocardial conditions, most current techniques are breath-held single-slice 2D acquisitions. We propose a free-breathing high-resolution isotropic 3D T2 mapping technique for the heart where breathing motion is corrected in k-space before image reconstruction. In 4 healthy volunteers and one patient with myocardial infarction, we found that our technique produced sharp and accurate T2 maps but had slightly lower precision than routine techniques.

Dongyue Si¹, Shuo Chen¹, Daniel A. Herzka², and Haiyan Ding^1
1Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University, Beijing, China, ²National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, United States

Three-dimensional (3D) T₂ mapping techniques enables quantitative detection of edematous tissue with whole heart coverage. However, the intrinsically long scan time limits its clinical application. In this study an accelerated 3D T₂ mapping sequence was developed based on low-rank plus sparsity reconstruction. Both retrospective and prospective experiments were performed to evaluate the accuracy and precision of the proposed method. Achieved image quality was comparable with 4 times acceleration. Homogeneous whole left ventricular T₂ map can be acquired in single breath-hold with resolution of 2×2×5 mm³.

Ruixi Zhou¹, Daniel S. Weller², Yang Yang³, Junyu Wang¹, John P. Mugler⁴, and Michael Salerno^5
1Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, ²Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, United States, ³Biomedical Engineering and Imaging Institute and Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, United States, ⁴Radiology, Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, ⁵Cardiology, Radiology, Biomedical Engineering, University of Virginia, Charlottesville, VA, United States

We propose a technique to acquire accurate B1 and T1 maps in a free-breathing cardiac self-gated continuous Look-Locker, inversion-recovery acquisition. Data are acquired using a single spiral interleaf, rotated by the golden-angle in time. During the first 2 seconds, off-resonance Fermi pulses are applied to generate a Bloch-Siegert shift B1 map, and the later data are acquired with an inversion RF pulse applied every four seconds to create T1* map. The final T1 map is generated with the B1 map and T1* map by using a look-up table to account for slice profile effects yielding more accurate T1 values.