Abstract
BackgroundThere is a renewed interest in lower field magnetic resonance imaging (MRI) systems for cardiovascular magnetic resonance (CMR), due to their favorable physical properties, reduced costs, and increased accessibility to patients with implants. We sought to assess the diagnostic capabilities of high-performance low-field (0.55 T) CMR imaging for quantification of right and left ventricular volumes and systolic function in both healthy subjects and patients referred for clinical CMR.MethodsSixty-five subjects underwent paired exams at 1.5 T using a clinical CMR scanner and using an identical CMR system modified to operate at 0.55 T. Volumetric coverage of the right ventricle (RV) and left ventricles (LV) was obtained using either a breath-held cine balanced steady-state free-precession acquisition or a motion-corrected free-breathing re-binned cine acquisition. Bland-Altman analysis was used to compare LV and RV end-systolic volume (ESV), end-diastolic volume (EDV), ejection fraction (EF), and LV mass. Diagnostic confidence was scored on a Likert-type ordinal scale by blinded readers.ResultsThere were no significant differences in LV and RV EDV between the two scanners (e.g., LVEDV: p = 0.77, bias = 0.40 mL, correlation coefficient = 0.99; RVEDV: p = 0.17, bias = − 1.6 mL, correlation coefficient = 0.98), and regional wall motion abnormality scoring was similar (kappa 0.99). Blood-myocardium contrast-to-noise ratio (CNR) at 0.55 T was 48 ± 7% of the 1.5 T CNR, and contrast was sufficient for endocardial segmentation in all cases. Diagnostic confidence of images was scored as “good” to “excellent” for the two field strengths in the majority of studies.ConclusionA high-performance 0.55 T system offers good bSSFP CMR image quality, and quantification of biventricular volumes and systolic function that is comparable to 1.5 T in patients.Trial registrationClinicaltrials.gov NCT03331380, NCT03581318.
Highlights
There is a renewed interest in lower field magnetic resonance imaging (MRI) systems for cardiovascular magnetic resonance (CMR), due to their favorable physical properties, reduced costs, and increased accessibility to patients with implants
We assessed whether the biventricular volumes, systolic function, and left ventricular (LV) mass acquired on a high-performance low-field (0.55 T) system would provide diagnostic data that were clinically comparable to those acquired on a standard 1.5 T clinical CMR scanner in patients referred for clinical CMR exams
Patient characteristics A total of 65 subjects (33 male, mean age 42.4 ± 15.5 years) underwent paired exams, with breath-held cine imaging used in 37 subjects and free-breathing rebinned cine imaging used in 28 subjects
Summary
There is a renewed interest in lower field magnetic resonance imaging (MRI) systems for cardiovascular magnetic resonance (CMR), due to their favorable physical properties, reduced costs, and increased accessibility to patients with implants. We sought to assess the diagnostic capabilities of high-performance low-field (0.55 T) CMR imaging for quantification of right and left ventricular volumes and systolic function in both healthy subjects and patients referred for clinical CMR. We recently demonstrated a research 0.55 T CMR system for cardiac imaging, with maintained magnet design and gradient performance [9]. This system configuration is capable of technically demanding cardiac imaging. We assessed whether the biventricular volumes, systolic function, and left ventricular (LV) mass acquired on a high-performance low-field (0.55 T) system would provide diagnostic data that were clinically comparable to those acquired on a standard 1.5 T clinical CMR scanner in patients referred for clinical CMR exams
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
