Robert Manka^1,2, Lukas Wissmann², Rolf Gebker³, Roy Jogiya⁴, Manish Motwani⁵, Michael Frick⁶, Sebastian Reinartz⁶, Bernhard Schnackenburg³, Markus Niemann², Alexander Gotschy¹, Christiane Kuhl⁶, Eike Nagel⁴, Eckart Fleck³, Thomas F Luescher¹, Sven Plein⁵, and Sebastian Kozerke^2,4
1University Hospital Zurich, Zurich, Switzerland, ²University and ETH Zurich, Zurich, Switzerland, ³German Heart Institute, Berlin, Germany, ⁴King's College London, United Kingdom, ⁵University of Leeds, United Kingdom, ⁶University Hospital Aachen, Germany

In this multi-center study the diagnostic performance of accelerated 3D myocardial perfusion imaging to detect functionally relevant coronary heart disease (CAD) was assessed relative to the invasive fractional flow reserve (FFR) reference standard. The sensitivity and specificity of myocardial ischemic burden as a metric to assess severity of CAD were 84.7% and 92.3% relative to the FFR reference confirming excellent diagnostic yield of 3D perfusion imaging in a multi-center setting.

David Chen^1,2, Behzad Sharif¹, Xiaoming Bi³, Janet Wei⁴, Louise E.J. Thomson^4,5, C. Noel Bairey Merz⁵, Daniel S Berman^1,4, and Debiao Li^1,6
1Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA, United States, ²Biomedical Engineering, Northwestern University, Evanston, IL, United States, ³MR R&D, Siemens Healthcare, Los Angeles, CA, United States, ⁴S. Mark Taper Foundation Imaging Center, Cedars Sinai Medical Center, Los Angeles, CA, United States, ⁵Barbara Streisand Women's Center, Cedars Sinai Medical Center, Los Angeles, CA, United States, ⁶David Geffen School of Medicine, University of California, Los Angeles, CA, United States

A single-bolus non-ECG-triggered method for quantifying myocardial blood flow is described. Beat-by-beat T1 mapping is used to derive the true arterial input function, eliminating the need for an additional scan. The imaging workflow is further simplified by retrospectively determining the proper reconstruction window, eliminating the dependency on ECG triggering. MBF values were validated compared to conventional dual-bolus ECG-triggered method. Stress studies were also performed to identify feasibility at elevated heart rates.

Yang Yang¹, Li Zhao², Xiao Chen¹, Peter Shaw³, Jorge Gonzalez³, Frederick Epstein^1,4, Craig Meyer^1,4, Christopher Kramer^3,4, and Michael Salerno^3,4
1Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, ²Radiology, Harvard University, Boston, MA, United States, ³Medicine, University of Virginia, Charlottesville, VA, United States, ⁴Radiology, University of Virginia, Charlottesville, VA, United States

As the heart occupies only a small fraction of the chest, it is inefficient to support a FOV that covers the whole chest. We developed an outer-volume suppressed single-shot spiral perfusion sequence to achieve whole heart coverage with high spatial and temporal resolution with a FOV that only included the heart. We demonstrate the successful application of reduced FOV single-shot perfusion imaging which improves sampling efficiently, and reduces residual aliasing artifacts resulting in high quality perfusion images with very high temporal (8ms) and spatial (2mm) resolution.

Karl Philipp Kunze¹, Christoph Rischpler¹, Shelley Zhang², Carmel Hayes³, Markus Schwaiger¹, and Stephan Nekolla^1
1Klinikum rechts der Isar der Technischen Universität München, München, Bayern, Germany, ²Brigham and Women's Hospital, Boston, MA, United States,³Siemens Medical Solutions, Erlangen, Bayern, Germany

This study aims to present a first synergistic approach to simultaneous MR/PET myocardial perfusion imaging. On the MR side, a new method to assess vascular dynamics by quantifying capillary transit time heterogeneity in different vasodilatation states is introduced. The advantages of transit time related perfusion parameters concerning quantification with MRI as compared to volume-related parameters such as flow are exploited for the first time with a specific physiological interpretation (oxygen extraction efficacy). MRI results are combined with an established method for flow quantification on the PET side, with patient data exemplifying the synergistic potential of the combined approach.

David A Broadbent^1,2, Ananth Kidambi², Sven Plein², and David L Buckley^1,2
1Division of Medical Physics, University of Leeds, Leeds, West Yorkshire, United Kingdom, ²Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds, West Yorkshire, United Kingdom

Dynamic Contrast Enhanced MRI has been used to quantify relative and absolute myocardial blood flow in health and disease. Measurement of additional parameters, including microvascular permeability and contrast agent distribution volumes, through application of a distributed parameter model, has also previously been reported. In this work these methods were applied in a cohort of patients with acute ST-Elevation Myocardial Infarction (STEMI) to allow assessment of these physiological parameters in infarcted and peri-infarct edematous myocardium.

Xiao Chen¹, Daniel Auger¹, Michael Salerno^2,3, Craig H. Meyer¹, Kenneth C. Bilchick⁴, and Frederick H. Epstein^1
1Biomedical Engineering, University of Virginia, Charlottesville, VA, United States, ²Radiology, University of Virginia, Charlottesville, VA, United States,³Cardiology, University of Virginia, Charlottesville, VA, United States, ⁴Medicine, Cardiovascular Medicine, University of Virginia, Charlottesville, VA, United States

3D Cine DENSE (Displacement ENcoding with Stimulated Echoes) imaging can offer, compared to tagging, high spatial resolution, equivalent accuracy and better reproducibility, and where strain analysis is less time consuming. However, the scan time is approximately 25 minutes, which is too long for routine clinical use. In the present study, we accelerated 3D spiral cine DENSE and shortened the scan time to ~3 minutes. High image quality was achieved and strain analysis showed expected values for normal subjects.

Andreas Greiser¹, Christoph Forman¹, Jens Wetzel², Michael Zenge³, Marie-Pierre Jolly⁴, and Edgar Mueller^1
1Siemens AG, Healthcare, Imaging & Therapy Systems, Magnetic Resonance, Erlangen, Bavaria, Germany, ²Department of Computer Science, Friedrich-Alexander-Universität Erlangen-Nuernberg, Pattern Recognition Lab, Erlangen, Bavaria, Germany, ³Siemens Healthcare, NY, United States, ⁴Imaging and Computer Vision, Siemens Corporate Technology, Princeton, NJ, United States

Myocardial strain imaging (MSI) using higher PAT acceleration in combination with iterative reconstruction was explored. Using a speed-up factor of 4, we propose A) multiple incremental applications of the tag preparation in different cardiac phases to increase the tag contrast, B) to cover two heartbeats after tag application to include a later heartbeat with virtually no tagging contrast to improve the quantitative strain analysis and C) to enable the estimation of a global T1 value from a tagging image series enabled by covering multiple heartbeats. Iterative reconstruction significantly improved the image appearance and tag visibility in accelerated MSI.

Jian Cao¹, Yining Wang¹, Lingyan Kong¹, Lu Lin¹, Yan Yi¹, Jing An², Tianjing Zhang², Michaela Schmidt³, Michael Zenge³, and Edgar Mueller^3
1Radiology, Peking Union Medical College Hospital, Beiing, Beijing, China, ²MR Collaborations NE Asia, Siemens Healthcare, Beijing, Beijing, China, ³Siemens AG, Allee am Röthelheimpark, Erlangen, 91052, Germany

We implemented a newly developed prototype sequence in patients with atrial fibrillation, which promises to achieve high acceleration factors which enable triggered 2D real-time CINE MRI with significantly improved spatial and/or temporal resolution.With the application of new sequence, we could acquire high-quality cardiac cine images while greatly reduce the scan time. In future, it could be applied in more clinical patients.

Jens Wetzl^1,2, Michaela Schmidt³, Michael O. Zenge³, Felix Lugauer¹, Laszlo Lazar⁴, Mariappan Nadar⁵, Andreas Maier^1,2, Joachim Hornegger^1,2, and Christoph Forman^3
1Pattern Recognition Lab, Department of Computer Science, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany, ²Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany, ³Siemens AG, Healthcare, Imaging & Therapy Systems, Magnetic Resonance, Erlangen, Germany, ⁴Siemens SRL, Corporate Technology, Brasov, Romania, ⁵Siemens Corporation, Corporate Technology, Princeton, NJ, United States

MR CINE acquisitions represent the gold standard for the assessment of left ventricular function. Although recently introduced single breath-hold real-time 2-D CINE and 3-D CINE acquisitions feature a high in-plane resolution, small details could be missed by the low spatial resolution in slice direction. To address this limitation, a single breath-hold 3-D CINE acquisition is proposed in this work featuring an isotropic resolution below 2 mm. In-vivo experiments were performed on 5 healthy volunteers and cardiac function was compared to gold standard 2-D CINE.

Rami Homsi¹, Alois M. Sprinkart^1,2, Julian Luetkens¹, Juergen Gieseke^1,3, Hans H. Schild¹, Michael Meier-Schroers¹, Daniel Kuetting¹, Darius Dabir¹, and Daniel Thomas^1
1Radiology, University Hospital Bonn, Bonn, NRW, Germany, ²Institute of Medical Engineering, Ruhr-University Bochum, Bochum, Germany, ³Philips Healthcare, Best, Netherlands

MRI is increasingly used to quantify pericardial fat volume. This study introduces a new method to quantify pericardial fat with a respiratory triggered 3D-Dixon sequence in healthy subjects. Results are correlated to parameters of cardiovascular risk such as BMI, age and pulse wave velocity.