El-Sayed H Ibrahim¹, Luba Frank¹, Sherry-Ann Brown¹, Jason Rubenstein¹, Rachel Schlaak¹, Elizabeth Gore¹, and Carmen Bergom^1
1Medical College of Wisconsin, Milwaukee, WI, United States

Radiation therapy (RT) is used by more than 50% of all cancer patients, where the risk of RT-induced cardiotoxicity reaches 33%. In this study, we investigate the role of cardiac contractility by MRI to differentiate the response of two different rat models to RT. The results showed the value of myocardial strain for early detection of RT-induced cardiotoxicity and exploring the effect of genetic profile and duration post-RT on cardiotoxicity. In conclusion, MRI strain imaging allows for determining spatial distribution and temporal progression of myocardial contractility post-RT, which would allow for determining the effect of genetic profile on cardiotoxicity development.

Ronald Mooiweer¹, Sarah McElroy², Giulio Ferrazzi³, Muhummad Sohaib Nazir², Carl Evans², Filippo Bosio², Nabila Mughal², Karl P Kunze⁴, Radhouene Neji⁴, Peter Speier⁵, Daniel Stäb⁶, Pier Giorgio Masci², Reza Razavi², Amedeo Chiribiri², and Sébastien Roujol^2
1King's College London, London, United Kingdom, ²School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, ³IRCCS San Camillo Hospital, Venice, Italy, ⁴MR Research Collaborations, Siemens Healthcare Limited, Frimley, United Kingdom, ⁵Siemens Healthcare GmbH, Erlangen, Germany, ⁶MR Research Collaborations, Siemens Healthcare Limited, Melbourne, Australia

SMS-bSSFP combined with compressed sensing was successfully used to acquire LGE images through the use of multiple single-shot dynamic acquisitions in one breath-hold. Instead of 1 slice per breath-hold, 3 slices could be acquired per breathhold.

Keyan Wang¹, Jingliang Cheng², Yang Yang³, and Jie Zheng^4
1MRI, 1st Affiliated Hospital of Zhengzhou University, Zhengzhou, China, ²1st Affiliated Hospital of Zhengzhou University, Zhengzhou, China, ³Icahn School of Medicine at Mount Sinai, New York, NY, United States, ⁴Mallinckrodt Institute of Radiology, Washington University in St, Washington, WA, United States

The study is to determine clinical utility of T1ρ to detect myocardial fibrosis in patients with hypertrophic cardiomyopathy (HCM) at different subtypes. The results showed that absolute T1ρ (ms) increased progressively and significantly from volunteer to HCM-N and then to HCM-H. ECV has the same trend as T1ρ. There was a strong positive correlation between ECV and T1ρ. If selecting T1ρ relaxation times of 36.5ms as the cutoff value for normal myocardial fibrosis, the sensitivity, specificity and AUC to detect myocardial fibrosis were 83.7%, 91.3%, and 0.937, respectively.T1ρ is able to detect early diffuse fibrosis in HCM and two subtypes.

Moses P. Cook¹, Wahiba Dhahri², Graham A. Wright^1,3,4, Michael A. Laflamme², and Nilesh R. Ghugre^1,3,4
1Medical Biophysics, University of Toronto, Toronto, ON, Canada, ²McEwen Centre for Regenerative Medicine, University Health Network, Toronto, ON, Canada, ³Schulich Heart Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada, ⁴Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada

Cardiac regenerative therapies using pluripotent stem cell-derived cardiomyocytes (PSC-CM, the graft) have shown promise in animal models of myocardial infarction. However, the mechanisms of structural integration of graft with host myocardium and the associated impact on function are less understood. 3D Diffusion Tensor Imaging (DTI) and contrast enhanced MRI were performed at 7T in ex vivo guinea pig hearts to quantify cardiac microstructure post PSC-CM transplantation. DTI parameters within the graft trended towards the healthy non-infarcted state, demonstrating a degree of anisotropic tissue repopulation within the infarct zone. MRI is a valuable marker for treatment efficacy in emerging regenerative therapies.

Dongyue Si¹, Yanfang Wu², Jie Yin², Rui Guo³, Jingjing Xiao⁴, Bowei Liu¹, Xue Lin², Peng Gao², Deyan Yang², Quan Fang², Jianwen Luo¹, Daniel A. Herzka⁵, and Haiyan Ding^1
1Center for Biomedical Imaging Research (CBIR), Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China, ²Department of Cardiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China, ³Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States, ⁴Department of Medical Engineering, Xinqiao Hosptial, Army Medical University, Chongqing, China, ⁵National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, United States

Cardiovascular magnetic resonance can provide functional and structural assessment of the left atrium and pulmonary veins, providing highly relevant pre- and post-procedural information in the treatment of atrial fibrillation (AF). In this study, an independent navigator-gated simultaneous dark blood late gadolinium enhancement and MR angiography sequence was developed for atrial scar detection. In 4 post AF ablation subjects, comparison with conventional phase sensitive inversion recovery images indicated that both scar-to-blood and blood-to-myocardium contrast were improved. Excellent correlation was observed between the scar measured by the proposed sequence and the low voltage areas observed with electroanatomical mapping.

Maxim Terekhov¹, Theresa Reiter², Michael Hock¹, David Lohr¹, Wolfgang Bauer^1,2, and Laura M. Schreiber^1
1Chair of Molecular and Cellular Imaging, University Hospital Würzburg, Comprehensive Heart Failure Center, Wuerzburg, Germany, ²Department of Internal Medicine I, Cardiology, University Hospital Würzburg, Wuerzburg, Germany

7T cardiac MRI is an emerging technique with the potential to increase the spatial resolution and functional informativity of the cardiac images. T₂*-quantification becomes a more sensitive MRI method at 7T compared to the lower B₀-fields and may provide valuable information on cardiac tissue remodeling. However, in practice, the value of T₂* at 7T as a marker of tissue alterations can be diminished by the suboptimal B₀-shimming  and problems of acquisition and analysis.  We present the results of the reproducibility and quality assurance study with 10 healthy volunteers for the optimization of T₂*-measurement protocol for a future clinical application.      

wen qian¹, kai gu², xiaoyue zhou³, yi xu¹, and xiaomei zhu^4
1The First Affiliated Hospital of Nanjing Medical University, Nanjing, China, ²Cardiovascular Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China, ³MR Collaboration, Siemens Healthineers Ltd., Shanghai, China, ⁴radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China

Cardiac magnetic resonance (CMR) is the gold standard for evaluating myocardial fibrosis. This study investigated the association between the occurrence and morphological features of ventricular arrhythmias (VAs) and left ventricular late gadolinium enhancement (LV-LGE) in patients without structural heart diseases. Seventy-eight patients with apparently normal hearts were enrolled and underwent simultaneous electrocardiogram and CMR examinations. Polymorphic VAs and ST-segment depression indicated a higher probability of having LV-LGE on CMR. The findings can help clinicians screen patients for CMR.

Divya Susanna Ninan¹ and Binita Riya Chacko^2
1Radiology, Christian Medical College Vellore, Vellore, India, ²Radiology, Christian Medical College, Vellore, Vellore, India

Novel cardiac MRI mapping techniques such as T1, T2 and ECV parametric mapping have been proven to detect early cardiotoxicity among patients taking chemotherapeutic drugs.  We aimed to determine whether these parameters could predict the development of early onset cardiac dysfunction in HER 2 positive breast cancer patients who were on anthracyclines and trastuzumab. We demonstrated statistically and clinically significant drop in left ventricular ejection fraction (LVEF) and right ventricular ejection fraction (RVEF) at four months post chemotherapy. The change in the mapping values were not statistically significant, however there was a trend towards an increase in the ECV.      

Changyu Sun¹, Kenneth C. Bilchick², Daniel Weller³, Michael Salerno^1,2,4, and Frederick H. Epstein^1,4
1Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, ²Medicine, University of Virginia, Charlottesville, VA, United States, ³Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, United States, ⁴Radiology, University of Virginia, Charlottesville, VA, United States

 k-t undersampled multiband first-pass perfusion imaging provides in-plane and through-plane acceleration and potentially enables high spatial resolution and whole-heart coverage. Our slice-L+S work splits MB data consistency and enforcing L+S into two subproblems wherein MB data, in- and through-plane coil information and L+S properties of slices are systematically utilized. Here we compare slice-L+S to single-band L+S and slice-GRAPPA followed sequentially by L+S (seq-SG-L+S) using 3 retrospectively undersampled datasets. High resolution nine-slice data with multiband factor-3 and rate-3 undersampling were prospectively acquired in 4 patients. Slice-L+S showed better image quality demonstrated by quantitative results and scores from two cardiologists. 

Tom Dresselaers^1,2, Ruben De Bosscher³, Sofie Tilborghs^4,5, Alexandru Cernicanu⁶, Christophe Dausin⁷, Oliver Ghekiere⁸, Rik Willems³, Guido Claessen³, and Jan Bogaert^1,2
1Radiology, UZ Leuven, Leuven, Belgium, ²Imaging and Pathology, KU Leuven, Leuven, Belgium, ³Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium, ⁴Department of Electrical Engineering (ESAT), KU Leuven, Leuven, Belgium, ⁵Medical Imaging Research Center, Medical Physics and Quality Assessment, KU Leuven, Leuven, Belgium, ⁶Philips Benelux, Eindhoven, Netherlands, ⁷Exercise Physiology Research Group, KU Leuven, Leuven, Belgium, ⁸Jessa Hospital, Hasselt, Belgium

We analysed differences in myocardial T1 between non-athletic subjects and athletes (which started endurance training early or late in life) to determine inter-center consistency. In addition, we implemented and extended MOLLI scheme (5s5s1s) to improve precision at very low heart rate typical in athlete's and compared with results from a standard 5s3s MOLLI.  Absolute levels were dependent on MOLLI scheme and site, but group differences were very similar as evident from full myocardium T1 histograms.

 

Yumin Li¹, Xiaoyue Zhou², Jia Liu¹, Yukun Cao¹, Xiaoyu Han¹, Guozhu Shao¹, Jin Gu¹, Tong Liu¹, Na Li¹, Yue Cui¹, and Heshui Shi^1
1Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China, ²MR Collaboration, Siemens Healthineers Ltd, ShangHai, China

This study aimed to determine the predictive value of non-invasive markers in patients with hypertrophic cardiomyopathy with preserved ejection fraction. The results demonstrated that an elevated level of N-terminal pro b-type natriuretic peptide (Nt-proBNP) was an independent predictor for the presence of late gadolinium enhancement (LGE), and combined with maximum wall thickness (MWT), had good diagnostic performance for the detection of LGE. Furthermore, decreased left ventricular global circumferential strain (GCS) was independently correlated with the LGE%, indicating its potential prognostic value for detecting myocardial fibrosis. 

Sudarshan Ragunathan¹, Ryan K Robison², Erik G Ellsworth³, and C Chad Quarles^1
1Barrow Neurological Institute, Phoenix, AZ, United States, ²Philips, Nashville, TN, United States, ³Phoenix Children's Hospital, Phoenix, AZ, United States

Clinical cardiac MRI protocols can be insensitive to secondary cardiomyopathy induced myocardium thickening and altered cardiac function. In this work, we demonstrate the feasibility of acquiring cardiac relaxivity contrast imaging (RCI) data, and specifically the RCI-parameter termed transverse relaxivity at tracer equilibrium (TRATE). TRATE has previously been shown to detect changes in cellular microstructure. RCI acquisition comprises of 1) pre-/post-contrast T₁ maps using a MOLLI protocol, and 2) pre-/post-contrast T₂^* maps using a multi-gradient echo protocol. Robust changes in post contrast R₂^*, and the subsequent TRATE values, support the potential role of using RCI to study myocardial microstructure changes.

Xuehua Shen¹, Yating Yuan², Xiaoyue Zhou³, Kelvin Chow⁴, Jens Wetzl⁵, and Bo Liang^2
1Department of Radiology, the Affiliated Hospital of Guizhou Medical University, Guiyang, China, China, ²Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China, Wuhan , China, China, ³MR Collaboration, Siemens Healthineers Ltd., Shanghai, China, Shanghai, China, China, ⁴MR R&D, Siemens Medical Solutions Inc., Chicago, USA, Chicago, USA, IL, United States, ⁵Siemens Healthcare GmbH, Erlangen, Germany, Erlangen, Germany, Germany

Cardiac magnetic resonance imaging has excellent tissue resolution and can quantitatively evaluate myocardial deformations and tissue characteristics. In this study, heart transplant (HT) patients had changed myocardial strain (LCGLS, LVGCS, and LVGRS) and tissue parameters (T1, T2, and ECV). There were also moderate correlations between these two different measurements. We suggest that myocardial movement is related to myocardial edema and fibrosis, and myocardial strain measurements could be an alternative to ECV with gadolinium injections.   

Cian Scannell¹, Torben Schneider², Ebraham Alskaf¹, Filippo Bosio¹, Joao Tourais³, Javier Sanchez-Gonzalez⁴, Mariya Doneva⁵, Christophe Schuelke⁵, Jakob Meineke⁵, Jochen Keupp⁵, Jouke Smink⁶, Marcel Breeuwer⁷, Amedeo Chiribiri¹, Markus Henningsson^8,9, and Teresa M Correia^1
1School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, ²Philips Healthcare, Guildford, United Kingdom, ³Magnetic Resonance Systems Lab, Delft University of Technology, Delft, Netherlands, ⁴Philips Healthcare Iberia, Madrid, Spain, ⁵Philips Research, Hamburg, Germany, ⁶MR Clinical Science, Philips Healthcare, Best, Netherlands, ⁷Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands, ⁸Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden, ⁹Center for Medical Image Science and Visualization (CMIV), Linköping University, Linköping, Sweden

First-pass perfusion cardiac MR (FP-CMR) is an essential tool for characterizing ischemic heart disease. Moreover, automated quantitative methods enable a reliable and operator-independent assessment of myocardial blood flow. Conventional FP-CMR has limited spatial resolution and is performed under breath-hold. Therefore, diagnostic accuracy is compromised by respiratory induced motion artifacts and false-positives due to dark-rim artifacts. To overcome these challenges, free-breathing Fat-water separation for mOtion-corrected Spatio-TEmporally accelerated myocardial peRfuSion (FOSTERS) has been proposed. Here, we implement and evaluate a high-resolution dual-echo Dixon version of FOSTERS and compare its quantitative performance to standard-resolution FP-CMR in patients with suspected cardiovascular disease.

Joao Tourais¹, Ingo Hermann^1,2, Rick Voncken³, Ömer Burak Demirel⁴, Sebastian Weingärtner¹, and Mehmet Akcakaya^4
1Magnetic Resonance Systems Lab, Department of Imaging Physics, TU Delft, Delft, Netherlands, ²Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany, ³Scannexus BV, Maastricht, Netherlands, ⁴Department for Electrical and Computer Engineering, and Center for Magnetic Resonance Research, University of Minnesota, Minnesota, MN, United States

Relaxation Along a Fictitious Field (RAFF) times in the 2^nd rotating frame (T_RAFF2) have shown promise for the depiction of acute myocardial infarct in a mouse model. In this work, in vivo myocardial T_RAFF2 maps are acquired in a single breath-hold at 3T. An additional image was acquired following saturation preparation to enable reconstruction with a three-parameter fit model. Visually high-quality map quality, homogeneous signal, artifact resilience and low inter-scan variability were achieved with T_RAFF2 in vivo. This makes T_RAFF2 an excellent candidate for myocardial tissue characterization in clinical use.

Xiaoying Cai^1,2, Selcuk Kucukseymen², Maria-Alexandra Olaru³, Patrick Pierce², Beth Goddu², Jennifer Rodriguez², and Reza Nezafat^2
1Siemens Medical Solutions USA, Inc., Boston, MA, United States, ²Department of Medicine, Cardiovascular Division, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, United States, ³Siemens Healthcare Limited GB&I, Frimley, United Kingdom

Cardiotoxicity remains a side effect of chemotherapy agents. Non-invasive imaging including cardiac MR has been applied to assess cardiac injury in patients receiving chemotherapy. Alterations in cardiac energetics have been reported in previous studies but have not been widely investigated in vivo. In this study, single voxel ¹H spectroscopy was applied to detect lipid metabolism changes in a large animal model. The results showed reduced myocardial triglycerides content in the doxorubicin-treated group in comparison with the control group.

Xiaobin Zhou¹, Xiaoyu Wei¹, Yingjie Mei², Qiong Ou³, Zhecheng Du⁴, and Hui Liu^1
1Department of Radiology, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China, ²Philips Healthcare, Guangzhou, China, ³Sleep Center, Department of Pulmonary and Critical Care Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangdong Provincial Geriatrics Institute, Guangzhou, China, ⁴Department of Medical Statistics, School of Public Health, Sun Yat-sen University, Guangzhou, China

The comprehensive assessment of left ventricular (LV) remodeling by cardiac magnetic resonance (CMR) imaging with T1 mapping and feature tracking (FT) technology in obstructive sleep apnea (OSA) was conducted in this study. Indexed extracellular volume (iECV) and indexed cellular volume (iCV) of myocardial tissue construction were derived from T1 mapping. The results show that elevated LV mass index (LVMi) in OSA was mainly from iCV, while not from iECV, with no LV ejection function (LVEF) or strain parameters impairment. Cellular hypertrophy accompanied with normal LV systolic function in patients with OSA may contribute to adaptive LV remodeling phase.

El-Sayed H Ibrahim¹, Marek Lenarczyk¹, and John Baker^1
1Medical College of Wisconsin, Milwaukee, WI, United States

The effect of exposure outside of the geometric radiation field on non-targeted organs as it results in cardiac disease is uncertain. Characterization of myocardial tissue abnormalities and cardiac dysfunction with cardiac MRI represents a valuable tool to define the presence and stage of a disorder at given timepoint. In this study, cardiac MRI was performed in an established rat model of irradiation injury to the non-targeted heart at different timepoints post irradiation. The results showed the value of myocardial strain and T1 measurements as sensitive markers of cardiovascular changes due to non-direct irradiation effect on the heart.

Bruce Damon¹, Margaret M. Samyn², Ke Yan², Aryaz Sheybani³, Wubishet Belay³, Justin Godown³, Lazaro Hernandez⁴, Kristen George-Durrett³, and Jonathan Soslow^3
1Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, United States, ²Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States, ³Pediatric Cardiology, Vanderbilt University Medical Center, Nashville, TN, United States, ⁴Pediatric Cardiology, Joe DiMaggio Children’s Hospital, Hollywood, FL, United States

Acute rejection (AR) remains a significant cause of morbidity and mortality in pediatric patients after heart transplant. Endomyocardial biopsy (EMB) of the right ventricular septum is the  standard method for diagnosing AR.  However, EMB is prone to additional risk and sampling error as AR is a heterogeneous process.  Here we show that extracellular volume fraction (ECV) mapping of the left ventricle (LV) analyzed with standard descriptive statistics and specialized texture analysis may differentiate pediatric heart transplant recipients as having AR or not. This CMR diagnostic approach offers diagnostic advantages including  greater sampling volume and minimal invasiveness.

Anoop Ayyappan¹, Harshith Kramadhari¹, Ajit Kumar¹, and Kapilamoorthy T.R.^1
1Department of IS & IR, Sree Chitra Tirunal Institute of Medical Sciences & Technology, Kerala, India

Hypertrophic cardiomyopathy (HCM) is a disorder of myocardium having a genetic basis, and  high disease related mortality. Identification of areas of occult fibrosis along with overt fibrosis using T1 mapping will be useful in long term prognosis of patients along with other imaging parameters in MRI.  This study was aimed at (a) determining the differences in native T1 values of controls and HCM patients, (b) to determine the relationship between early gadolinium enhancement (EGE)/Late gadolinium enhancement (LGE)/ perfusion abnormalities and native T1 and ECV values in patients of hypertrophic cardiomyopathy.