Ronald Mooiweer¹, Radhouene Neji², Sarah McElroy¹, Muhummad Sohaib Nazir¹, Reza Razavi¹, Amedeo Chiribiri¹, and Sébastien Roujol^1
1School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, ²MR Research Collaborations, Siemens Healthcare, Frimley, United Kingdom

A fast respiratory navigator (fastNAV) was developed for dynamic contrast enhanced CMR perfusion imaging by combining spatially non-selective saturation with slice-selective tip-up and slice-selective excitation pulses. A calibration scan was developed to enable the estimation of subject-specific tracking factors. Prospective motion correction using fastNAV was applied to perfusion imaging in 10 patients under free-breathing conditions. Compared to conventional perfusion imaging, fastNAV reduced the effect of respiratory motion while no difference in image quality was observed.

Caroline Colbert^1,2,3, Michael A. Thomas^3,4, Ran Yan^2,5, Hengjie Liu^1,2, Peng Hu^1,2,5, and Kim-Lien Nguyen^1,2,3
1Physics and Biology in Medicine Graduate Program, UCLA David Geffen School of Medicine, Los Angeles, CA, United States, ²Department of Radiology, UCLA David Geffen School of Medicine, Los Angeles, CA, United States, ³Division of Cardiology, UCLA David Geffen School of Medicine, Los Angeles, CA, United States, ⁴Department of Radiology, Northwestern School of Medicine, Chicago, IL, United States, ⁵Department of Bioengineering, UCLA Samueli School of Engineering, Los Angeles, CA, United States

We aimed to evaluate the feasibility of an abbreviated MRI protocol for estimation of fractional myocardial blood volume (fMBV). Four normal swine were imaged with the MOLLI sequence at baseline and following seven ferumoxytol doses. We estimated fMBV using our full dataset, after application of retrospective dose under-sampling, and with the fast-exchange approximation. A four-acquisition protocol with compartmental modelling may have potential to accurately estimate fMBV in studies of myocardial perfusion.

Lu Lin¹, Jian Wang¹, René M Botnar ², Claudia Prieto², Jing An³, Michaela Schmidt⁴, Christoph Forman⁴, Karl philipp kunze⁵, Zhengyu Jin¹, and Yining Wang^1
1Peking union medical college hospital, Beijing, China, ²School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, ³Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, China, ⁴Siemens Healthcare GmbH, Erlangen, Germany, ⁵Siemens Healthcare Limited, London, United Kingdom

This study sought to evaluate the clinical feasibility, image quality and diagnostic accuracy of a prototype 3T post-contrast high-resolution whole-heart coronary MR angiography (CMRA) sequence with image-navigator (iNAV) based motion correction and 100% respiratory scan efficiency integrated into clinical cardiac MR scan before LGE imaging. The results showed CMRA imaging completed on average in 5.2minutes with promising image quality. CMRA showed good inter-modality agreement compared to computed tomography angiography (CTA) and high negative predictive value (NPV), which allows effective exclusion of coronary artery disease. 

Reza Hajhosseiny¹, Imran Rashid¹, Aurélien Bustin¹, Camila Munoz¹, Gastao Cruz¹, Muhummad Sohaib Nazir¹, Karine Grigoryan¹, Tevfik F. Ismail¹, Rebecca Preston², Radhouene Neji^1,3, Karl Kunze^1,3, Reza Razavi¹, Amedeo Chiribiri¹, Pier Giorgio Masci¹, Ronak Rajani¹, Claudia Prieto¹, and René M. Botnar^1
1School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, ²Department of Radiology, Guy’s and St Thomas’ NHS Foundation Trust, London, United Kingdom, ³MR Research Collaborations, Siemens Healthcare Limited, Frimley, United Kingdom

Conventional coronary magnetic resonance angiography (CMRA) is limited by long and unpredictable acquisition-times, low spatial resolution and motion related image quality degradation. To overcome these challenges, we have proposed a highly undersampled acquisition with image-based navigators and non-rigid motion correction to enable high resolution (0.9mm3) CMRA with ≈11min acquisition time. In 30 patients with suspected coronary artery disease (CAD) who also underwent a coronary computed tomography angiography (CCTA), our CMRA framework achieved excellent image quality across all coronary artery segments, with a per patient sensitivity of 100%, specificity of 68% and negative predictive value of 100% for identifying/excluding significant CAD.

Takashige Yoshida¹, Takashige Yoshida¹, Masami Yoneyama², Jihun Kwon², Kohei Yuda³, Yuki Furukawa³, and Nobuo Kawauchi^3
1radiology, Tokyo metropolitan police hospital, Tokyo, Japan, ²Philips Japan, Tokyo, Japan, ³Tokyo metropolitan police hospital, Tokyo, Japan

One of the problems of whole heart coronary MRA is the prolongation of acquisition time, and the radial sampling technique is able to obtain the image of inconspicuous artifacts such as aliasing and motion. Furthermore, the improved sequence of 3D d-Vane is possible to adopt a self-navigator without extend scan time. Hence the small FOV whole heart coronary MRA with diamond pseudo golden angle radial sampling showed improved efficiency with maintaining the image quality.

Zhiyong Chen¹, Bin Sun¹, Yunjing Xue¹, Qing Duan¹, ZhongShuai Zhang², and Jing An^3
1Radiology, Union Hospital, School of Medical Technology and Engineering, Fujian Medical University, Fuzhou, China, ²Diagnostic imaging, Siemens Healthcare, Shanghai, China., Shanghai, China, ³Siemens Shenzhen Magnetic Resonance Ltd., Shenzhen, China., Shenzhen, China

this study demonstrated the feasibility of CE-CMRA for detection of myocardial hyperemia in patients with suspected acute myocarditis. Furthermore, this approach could serve as a helpful supplementary tool to assess coronary artery significant stenosis. The results of the present study suggested that CE-CMRA may potentially improve accuracy of evaluating the original Lake Louise Criteria to identify acute myocarditis in combination with T2-STIR and LGE imaging. 

Yang Wu¹, Xiaojing Ma¹, Weiwei Wang¹, Feng Xiong¹, Ke Yu¹, Jiazheng Wang², Peng Sun², and Qingping gu^2
1MRI department, Wuhan Asia Heart General Hospital, WuHan, China, ²philips, healthcare, Beijing, China

Diagnosis of Coronary artery disease using MRI remains a challenge due to the long scan times, limited spatial resolution, and low signal-to-noise of MRI technique. Compressed Sensing (CS) is a novel technique to accelerate the imaging and improve detection of coronary stenosis by coronary MRI. Results of this study indicate that there was no statistical difference in coronary artery image quality from the scanning with CS acceleration factors (AF) of 2, 4, 6. Since CS AF of 6 provides the shortest scan time and favorable image quality, this might be an optimal setting for clinical whole-heart coronary MRI.

Robert R Edelman^1,2, Nondas Leloudas³, Jianing Pang⁴, and Ioannis Koktzoglou^3,5
1Radiology, NorthShore University HealthSystem, EVANSTON, IL, United States, ²Feinberg School of Medicine, Northwestern University, Chicago, IL, United States, ³Radiology, NorthShore University HealthSystem, Evanston, IL, United States, ⁴Siemens Medical Solutions USA, Chicago, IL, United States, ⁵Pritzker School of Medicine, University of Chicago, Chicago, IL, United States

We recently described a novel class of steady-state pulse sequence called T1 Relaxation-Enhanced Steady-State (T₁RESS).  The unbalanced variant, called uT₁RESS, generates dark blood images without the need to apply additional preparation modules.  We sought to determine whether an electrocardiogram (ECG)-gated implementation of uT₁RESS could be used to generate dark blood images for evaluation of the heart and great vessels.  A pilot study of healthy volunteers and patients undergoing cardiac MRI was approved by the hospital institutional review board.  Initial results suggest that ECG-gated uT₁RESS shows promise for  volumetric multi-contrast evaluation of the heart and great vessels. 

Kazuo Kodaira¹, Michinobu Nagao², Masami Yoneyama³, Yasutomo Katsumata³, Takumi Ogawa¹, Yutaka Hamatani¹, Isao Shiina¹, Yasuhiro Goto¹, Mamoru Takeyama¹, Isao Tanaka¹, and Shuji Sakai^2
1Department of Radiological Services, Tokyo Women's Medical University Hospital, tokyo, Japan, ²Department of Diagnostic imaging & Nuclear Medicine, Tokyo Women's Medical University Hospital, tokyo, Japan, ³Philips Japan, tokyo, Japan

Diaphragmatic one-dimensional navigation (NAV) is the conventional approach for CMRA respiratory motion compensation. This method has limitations such as the cumbersomeness of setting NAV and giving stresses to patients by wrapping the compression band around the chest/abdomen for minimizing respiratory artifacts. Image-based 2D navigator (iNAV) can solve this limitation because it directly corrects the translational movement of the heart in two directions (R-L and F-H) by using 2D real-time imaging. We investigate the feasibility of iNAV with loosely wrapped abdominal compression band compared to the conventional NAV approach.

Koji Matsumoto¹, Hajime Yokota², Takafumi Yoda ¹, Ryota Ebata³, Hiroki Mukai¹, Yoshitada Masuda¹, and Takashi Uno^2
1Department of Radiology, Chiba University Hospital, Chiba, Japan, ²Diagnostic Radiology and Radiation Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan, ³Department of Pediatrics, Chiba University Hospital, Chiba, Japan

We performed qualitative and quantitative evaluations of cross-sectional coronary vessel wall images collected by 3D-TSE and 2D-DIR-TSE in Kawasaki disease (KD) and assessed the reproducibility of both. Coronary vessel walls were evaluated separately in aneurysmal and normal regions. 3D-TSE was comparable to 2D-DIR-TSE in visual assessment and has reproducibility of 3D of lumen area (LA), wall area (WA), normalized wall index (NWI = WA / (LA + WA) ), and lumen-cardiac wall contrast measurements. 3D-TSE coronary vessel wall imaging can collect wide FOV and accurate cross-sectional images, and is feasible for following up the coronary arteries of KD.

Thomas Joyce¹, Stefano Buoso¹, Christian T Stoeck¹, and Sebastian Kozerke^1
1University and ETH Zurich, Zurich, Switzerland

We present a novel method for volumetric left ventricle mesh personalisation from cardiac MR images. The proposed method does not require any ground-truth mesh training data. Additionally, it corrects for slice misalignment and can propagate these correction back to the original image data. The method is expressive enough to capture diverse morphology, and is also differentiable, allowing for direct inclusion in deep-learning pipelines. We demonstrate that our mesh personalisation approach works robustly on both healthy and pathological anatomy.

yang chen¹, Pan pan Xu¹, Xiao yue Zhou², Yi Xu¹, and Xiao mei Zhu^1
1the First Affiliated Hospital of Nanjing Medical University, Nanjing, China, ²Siemens Healthineers Ltd, Shanghai, China

Left atrial (LA) size is a useful measurement in predicting adverse cardiovascular outcomes. The current study compared LA volume accuracy and strain analysis between conventional segmented cine cardiac magnetic resonance (CMR) and single-shot compressed sensing (CS) cine CMR in 31 and 30 patients with and without left ventricular (LV) diastolic dysfunction, respectively. In both techniques, LA passive ejection fraction and passive radial and longitudinal strain showed diagnostic efficacy for LV diastolic dysfunction, and volume accuracies were not significantly different between techniques. CS cine CMR can reliably assess LA volume and strain in patients who are at risk for cardiovascular diseases.  

Cailing Pu¹, Jingle Fei¹, Yan Wu¹, Chengbin He¹, and Hongjie Hu^1
1Radiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China

Myocardial strain parameters detected by tissue tracking on cardiac magnetic resonance (CMR-TT) were helpful for early prediction of myocardial damage in patients with hypertrophic cardiomyopathy (HCM). Global circumferential strain (GCS) and late gadolinium enhancement (LGE) percentage were reliable and independent predictors for ventricular arrhythmias (VAs) in HCM. For patients who can’t undergo the LGE scan, reduced GCS may have potential value to identify HCM patients with the risk of VAs.

Hugo Klarenberg¹, Mark Gosselink², Martijn Froeling², Tim Leiner², Aart J. Nederveen³, Adrianus J. Bakermans³, Hildo J. Lamb⁴, S. Matthijs Boekholdt⁵, and Gustav J. Strijkers^1
1Biomedical Engineering & Physics, Amsterdam UMC, Amsterdam, Netherlands, ²Radiology, University Medical Center Utrecht, Utrecht, Netherlands, ³Radiology and Nuclear Medicine, Amsterdam UMC, Amsterdam, Netherlands, ⁴Radiology, Leiden University Medical Center, Leiden, Netherlands, ⁵Cardiology, Amsterdam UMC, Amsterdam, Netherlands

Currently, a standard short-axis cardiac CINE protocol consists of ~7 breath-holds which is time-consuming, costly and patient-unfriendly. We investigated whether it is feasible to accurately quantify biventricular morphology and function in 3 to 2 breath-holds using a new 72‑channel receive array and (compressed-)SENSE acceleration. To that end, we performed a comparison between a 16 channel local array with a SENSE-factor 2 and the new coil with (compressed‑) SENSE factors of 2, 4 and 6. In all cases, left ventricular ejection fractions were similar with acceptable image quality decline for higher acceleration, facilitating cardiac function assessment in only 2 breath-holds.

Marcus Hott^1,2,3, Henrik von Kleist⁴, Jihye Jang^2,5, Andrew Powell^1,2, and Mehdi Hedjazi-Moghari^1,2
1Department of Pediatrics, Harvard Medical School, Boston, MA, United States, ²Department of Cardiology, Boston Children's Hospital, Boston, MA, United States, ³Department of Informatics, Technical University of Munich, Munich, Germany, ⁴Munich School for Data Science, Munich, Germany, ⁵Philips Healthcare, Gainesville, FL, United States

We implemented an end-to-end cardiac self-gating algorithm for a novel free-breathing 2D cine phase-contrast sequence on a clinical MRI scanner. We validated our technique against clinically performed ECG-gated cine phase-contrast scan. Strong agreement with no statistically significant difference was shown between the systemic and pulmonary blood flow measurements calculated between the standard ECG-gating and self-gating scans. Our approach eliminates the need for an ECG signal and allows for blood flow measurements where an ECG is not accessible such as fetal cardiac MRI.  

Zheng Zhong^1,2, Qingfei Luo¹, Kaibao Sun¹, Guangyu Dan^1,2, Muge Karaman^1,2, and Xiaohong Joe Zhou^1,2,3,4
1CMRR, University of Illinois at Chicago, Chicago, IL, United States, ²Bioengineering, University of Illinois at Chicago, Chicago, IL, United States, ³Neurosurgery, University of Illinois at Chicago, Chicago, IL, United States, ⁴Radiology, University of Illinois at Chicago, Chicago, IL, United States

An imaging technique, coined epi-based Sub-millisecond Periodic Event Encoded Dynamic Imaging, or epi-SPEEDI, has been shown capable of visualizing the rapid opening and closing of human aortic valve with sub-millisecond temporal resolution. However, the acquisition time of epi-SPEEDI was relatively long (8-10 breath holds). Herein, we report an alternative SPEEDI technique with a reduced FOV, which we call rFOV-SPEEDI, to shorten the scan times. This technique has been successfully applied to visualization of human aortic valve opening and closing with a temporal resolution of 0.6 ms, together with a scan time reduction of 32.5%.

Isao Shiina¹, Michinobu Nagao², Masami Yoneyama³, Yasutomo Katsumata³, Yasuhiro Goto⁴, Kazuo Kodaira⁴, Takumi Ogawa⁴, Yutaka Hamatani¹, Mamoru Takeyama⁴, Isao Tanaka⁴, and Shuji Sakai^2
1Radiological Services, Tokyo Women's Medical University Hospital, tokyo, Japan, ²Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Women's Medical University Hospital, Tokyo, Japan, ³Philips Electronics Japan, Tokyo, Japan, ⁴Department of Radiological Services, Tokyo Women's Medical University Hospital, Tokyo, Japan

we investigate the clinical usefulness of respiratory-triggered cardiac cine radial MRI. Compared with the breath-hold scan, the left ventricular function values obtained from the breath-triggered scan showed a better correlation than the conventional free-breathing scan.

Chiara Manini¹, Lennart Tautz^1,2, Alireza Khasheei³, Titus Kühne^1,4, Christoph Kolbitsch⁵, Jeanette Schulz-Menger^1,4, and Anja Hennemuth^1,2,4
1ICM, Charité - Universitätsmedizin Berlin, Berlin, Germany, ²Fraunhofer MEVIS, Bremen, Germany, ³Deutsches Herzzentrum Berlin, Berlin, Germany, ⁴German Center for Cardiovascular Research (DZHK), Partner Site Berin, Germany, ⁵Physikalisch-technische Bundesanstalt, Berlin, Germany

Diagnostic assessment of the mitral valve considers pathological alterations in anatomy as well as their effect on cardiac function. The goal of our work was to evaluate, whether the mitral valve anatomy could be assessed with diagnostic precision based on MRI imaging using standard (SLA) or rotational long axis (RLA) cine MRI. In a preliminary study, 6 healthy volunteers underwent imaging in a 1.5T scanner with both approaches. We generated 3D models for the quantitative assessment of the shape of the valves and achieve a higher precision based on the RLA image data.

Jyothsna Akam Venkata^1,2, Mohamed Abdelghafar Hussein^1,3, Joshua Greer¹, Robert Jaquiss⁴, Gerald Greil¹, Jeanne Dillenbeck¹, Surendrenath R Veeram Reddy ¹, Jenifer Hernandez¹, and Tarique Hussain^1
1Dept of Pediatrics, Division of Pediatric Cardiology, UT Southwestern Medical Center, Dallas, TX, United States, ²University of Mississippi Medical Center, Jackson, MS, United States, ³Kafrelsheikh University, Kafr Elsheikh, Egypt, ⁴Department of Pediatric Cardiothoracic Surgery, UT Southwestern Medical Center, Dallas, TX, United States

Pre-Fontan cardiac assessment with CMR in conjunction with cardiac catheterization has increasingly become the standard of care. Cardiac catheterization and CMR performed for pre-Fontan assessment at a single institution between April 2017 and June 2020 were analyzed. Our cohort consisted of 43 patients with median age of 3.7 years(range 1.8-14) at the time of CMR. Median age at Fontan operation was 4 years (2.4-14). We found significant correlation between CMR derived ventricular end diastolic, end systolic volume, ejection fraction and cardiac catheterization derived ventricular end-diastolic and mean superior vena cava pressure, and duration of post-operative hospital stay after Fontan operation. 

Makoto Orii¹, Tsuyoshi Sugawara¹, Hidenobu Takagi¹, Martin A Janich², Atsushi Nozaki³, and Kunihiro Yoshioka^1
1Iwate Medical University, Yahaba, Japan, ²GE Healthcare, Munich, Germany, ³GE Healthcare, Tokyo, Japan

To assess the image quality, reproducibility, and accuracy of two-dimensional (2D)-cine k-adaptive-t Autocalibrating Reconstruction for Cartesian sampling (2D kat-ARC) for the quantification of biventricular volumes and function compared to 2D balanced steady state free precession (2D SSFP) in patients with repaired tetralogy of Fallot (TOF). In this study, we were able to find good reproducibility of biventricular volumes and ejection fraction (EF) between 2D SSFP and 2D kat-ARC sequences despite some drawbacks including an overestimation of right ventricular (RV) end-systolic volume and an underestimation of RV stroke volume and RVEF compared to 2D SSFP.