Reproducibility of Cardiac Multifrequency MR Elastography in Assessing Left Ventricular Stiffness and Viscosity

Johannes Castelein; Amanda S Duus; Pernille S Bække; Ingolf Sack; Matthias S Anders; Karen Kettless; Adam E Hansen; Rudi A J O Dierckx; Ole De Backer; Niels G Vejlstrup; Morten A V Lund; Ronald J H Borra

doi:10.1002/jmri.29640

Reproducibility of Cardiac Multifrequency MR Elastography in Assessing Left Ventricular Stiffness and Viscosity

J Magn Reson Imaging. 2024 Oct 25. doi: 10.1002/jmri.29640. Online ahead of print.

Authors

Johannes Castelein^{1

2}, Amanda S Duus², Pernille S Bække³, Ingolf Sack⁴, Matthias S Anders⁴, Karen Kettless⁵, Adam E Hansen^{6

7}, Rudi A J O Dierckx⁸, Ole De Backer³, Niels G Vejlstrup³, Morten A V Lund^{2

3}, Ronald J H Borra^{1

8}

Affiliations

¹ Department of Radiology, University Medical Center Groningen, Groningen, The Netherlands.
² Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
³ The Heart Centre, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
⁴ Department of Radiology, Charite-Universitätsmedizin Berlin, Berlin, Germany.
⁵ Deparment of Research and Collaboration, Siemens Healthcare A/S, Ballerup, Denmark.
⁶ Department of Radiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
⁷ Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark.
⁸ Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen, The Netherlands.

PMID: 39449547
DOI: 10.1002/jmri.29640

Abstract

Background: Cardiac magnetic resonance elastography (MRE) shows promise in assessing the mechanofunctional properties of the heart but faces clinical challenges, mainly synchronization with cardiac cycle, breathing, and external harmonic stimulation.

Purpose: To determine the reproducibility of in vivo cardiac multifrequency MRE (MMRE) for assessing diastolic left ventricular (LV) stiffness and viscosity.

Study type: Prospective.

Subjects: This single-center study included a total of 28 participants (mean age, 56.6 ± 23.0 years; 16 male) consisting of randomly selected healthy participants (mean age, 44.6 ± 20.1 years; 9 male) and patients with aortic stenosis (mean age, 78.3 ± 3.8 years; 7 male).

Field strength/sequence: 3 T, 3D multifrequency MRE with a single-shot spin-echo planar imaging sequence.

Assessment: Each participant underwent two cardiac MMRE examinations on the same day. Full 3D wave fields were acquired in diastole at frequencies of 80, 90, and 100 Hz during a total of three breath-holds. Shear wave speed (SWS) and penetration rate (PR) were reconstructed as a surrogate for tissue stiffness and inverse viscous loss. Epicardial and endocardial ROIs were manually drawn by two independent readers to segment the LV myocardium.

Statistical tests: Shapiro-Wilk test, Bland-Altman analysis and intraclass correlation coefficient (ICC). P-value <0.05 were considered statistically significant.

Results: Bland-Altman analyses and intraclass correlation coefficients (ICC = 0.96 for myocardial stiffness and ICC = 0.93 for viscosity) indicated near-perfect test-retest repeatability among examinations on the same day. The mean SWS for scan and re-scan diastolic LV myocardium were 2.42 ± 0.24 m/s and 2.39 ± 0.23 m/s; the mean PR were 1.24 ± 0.17 m/s and 1.22 ± 0.14 m/s. Inter-reader variability showed good to excellent agreement for myocardial stiffness (ICC = 0.92) and viscosity (ICC = 0.85).

Data conclusion: Cardiac MMRE is a promising and reproducible method for noninvasive assessment of diastolic LV stiffness and viscosity.

Level of evidence: 2 TECHNICAL EFFICACY: 1.

Keywords: left ventricle; magnetic resonance elastography; noninvasive; tissue stiffness; tomoelastography.