Rapid, Efficient Imaging

1350951 - Reproducibility of Oxygenation-Sensitive Cardiac Magnetic Resonance Breathing-Induced Myocardial Oxygenation Reserve Across Scan Vendors and Field Strengths

Wednesday, January 25, 2023

5:00 PM – 6:30 PM

Location: Silver Pearl 1

Presenting Author(s)

KL

Kate S. Lindsay, MSc

PhD Student
McGill University
Beaconsfield, Quebec, Canada

Primary Author(s)

KL

Kate S. Lindsay, MSc

PhD Student
McGill University
Beaconsfield, Quebec, Canada

Co-Author(s)

EH

Elizabeth Hillier, PhD

Research Scientist
McGill University, University of Alberta
Montreal, Quebec, Canada
JL

Judy Luu, MD, PhD, FSCMR

Cardiologist
Research Institute of the McGill University Health Center, Canada
MB

Mitchel Benovoy, PhD

PhD
Area19 Medical Inc, Montreal, Canada, H2V 2X5
Montreal, Quebec, Canada
ML

Margherita Leo, MRT (R) (ACR)

Cardiac MRI Technologist
Research Institute of the McGill University Health Center
Montreal, Quebec, Canada
SG

Sylvie Gelineau, MRT

Cardiac MRI Technologist
Research Institute of the McGill University Health Center, Canada
Matthias G. Friedrich, MD, FSCMR

Senior Author
Research Institute of the McGill University Health Center
Montreal, Quebec, Canada

Background: Oxygenation-Sensitive Cardiac Magnetic Resonance (OS-CMR) is a validated tool to examine vascular function using the breathing-induced myocardial oxygenation reserve (B-MORE) (Fischer et al., 2018, Hillier et al., 2022). However, the interpretation of published B-MORE values has been limited to Siemens scanners, and the reproducibility of B-MORE values across repeated scans is yet unknown. Additionally, field strength may confound the interpretation of B-MORE values, with the contrast between normal and deoxygenated myocardium increased at higher field strengths. The aim of this preliminary study was to assess the reproducibility of B-MORE values acquired during consecutive OS-CMR scans among different scanners and field strengths.

Methods:

We conducted a single-centre, retrospective study and measured B-MORE in images from 3 different scans in each subject using a vasoactive breathing maneuver, composed of a period of paced hyperventilation followed by a voluntary maximal breath hold. Scans were performed consecutively using a 1.5 T Artist (GE Medical Systems), a 3 T Premier (GE Medical Systems), and a 3 T Skyra (Siemens Healthineers). B-MORE values were calculated from the first post-hyperventilation end-systolic image and the end-systolic image closest to 30 seconds of the breath hold. Repeated-measures ANOVA was used to view differences in basal slice, mid slice, and global B-MORE across the three scans.

Results:
We performed 27 OS-CMR scans in 9 healthy adults (44% female, mean age= 40 years). Mean global B-MORE values were 8.4%, 8.0%, and 3.2% on the Siemens Skyra, GE Premier, and GE Artist, respectively. Global B-MORE results were not significantly different between the three scans (p=0.25) in ANOVA analysis. Mean basal B-MORE values were 8.1%, 8.2%, and 4.3% on the Siemens Skyra, GE Premier, and GE Artist, respectively. Basal slice B-MORE results were not significantly different between the three scans (p=0.65). Mean mid-slice B-MORE values were 8.6%, 7.9%, and 2.3% on the Siemens Skyra, GE Premier, and GE Artist, respectively, and were significantly different on ANOVA analysis (p=0.04).

Conclusion:
These preliminary results indicate that global B-MORE values are reproducible across scan vendors. Field strength, however, appears to be a significant confounder, with observed values being lower at 1.5T when compared to 3T values. Further studies with larger sample sizes are necessary to conclusively quantify the effect of field strength and its impact on clinical application.