Cardiac MR elastography for quantitative assessment of elevated myocardial stiffness in cardiac amyloidosis

• Published in: Journal of magnetic resonance imaging Vol. 46; no. 5; pp. 1361 - 1367
• Main Authors: Arani, Arvin, Arunachalam, Shivaram P., Chang, Ian C.Y., Baffour, Francis, Rossman, Phillip J., Glaser, Kevin J., Trzasko, Joshua D., McGee, Kiaran P., Manduca, Armando, Grogan, Martha, Dispenzieri, Angela, Ehman, Richard L., Araoz, Philip A.
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.11.2017; John Wiley and Sons Inc
• Subjects: Amyloid; Amyloidosis; cardiac amyloidosis; cardiac MRE; Diagnostic systems; Feasibility studies; Heart diseases; magnetic resonance elastography; Magnetic resonance imaging; Measurement methods; myocardial stiffness; Noise threshold; Original Research; Patients; quantitative stiffness imaging; Shear strain; Stiffness; Supine position; Ventricle; Vibration; cardiac MRE; cardiac amyloidosis; quantitative stiffness imaging; myocardial stiffness; magnetic resonance elastography
• ISSN: 1053-1807; 1522-2586
• DOI: 10.1002/jmri.25678

Purpose To evaluate if cardiac magnetic resonance elastography (MRE) can measure increased stiffness in patients with cardiac amyloidosis. Myocardial tissue stiffness plays an important role in cardiac function. A noninvasive quantitative imaging technique capable of measuring myocardial stiffness could aid in disease diagnosis, therapy monitoring, and disease prognostic strategies. We recently developed a high‐frequency cardiac MRE technique capable of making noninvasive stiffness measurements. Materials and Methods In all, 16 volunteers and 22 patients with cardiac amyloidosis were enrolled in this study after Institutional Review Board approval and obtaining formal written consent. All subjects were imaged head‐first in the supine position in a 1.5T closed‐bore MR imager. 3D MRE was performed using 5 mm isotropic resolution oblique short‐axis slices and a vibration frequency of 140 Hz to obtain global quantitative in vivo left ventricular stiffness measurements. The median stiffness was compared between the two cohorts. An octahedral shear strain signal‐to‐noise ratio (OSS‐SNR) threshold of 1.17 was used to exclude exams with insufficient motion amplitude. Results Five volunteers and six patients had to be excluded from the study because they fell below the 1.17 OSS‐SNR threshold. The myocardial stiffness of cardiac amyloid patients (median: 11.4 kPa, min: 9.2, max: 15.7) was significantly higher (P = 0.0008) than normal controls (median: 8.2 kPa, min: 7.2, max: 11.8). Conclusion This study demonstrates the feasibility of 3D high‐frequency cardiac MRE as a contrast‐agent‐free diagnostic imaging technique for cardiac amyloidosis. Level of Evidence: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1361–1367.