7-Tesla Cardiac MRI for Ventricular and Valvular quantitation in healthy volunteers
Author(s)
Hamilton-Craig, C
Staeb, D
O'Brien, K
Galloway, G
Barth, M
Griffith University Author(s)
Year published
2018
Metadata
Show full item recordAbstract
Background: Ultra-high-field (B0 ≥7 Tesla) cardiovascular magnetic resonance (CMR) offers increased resolution, but cardiac imaging requiring ECG gating is significantly impacted from the magneto-hydrodynamic (MHD) effect, distorts the ECG trace (1–3). Previously, 7T CMR was constrained to using pulse oximetry for triggering, We explored the technical feasbility of a 7 T research MR scanner using of-the-art ECG trigger algorithm to assess left and right ventricular volumes, aortic and pulmonary valve flow.
Methods: 7T CMR scans were performed on 10 healthy volunteers on whole-body research MRI scanner (Siemens Healthcare, ...
View more >Background: Ultra-high-field (B0 ≥7 Tesla) cardiovascular magnetic resonance (CMR) offers increased resolution, but cardiac imaging requiring ECG gating is significantly impacted from the magneto-hydrodynamic (MHD) effect, distorts the ECG trace (1–3). Previously, 7T CMR was constrained to using pulse oximetry for triggering, We explored the technical feasbility of a 7 T research MR scanner using of-the-art ECG trigger algorithm to assess left and right ventricular volumes, aortic and pulmonary valve flow. Methods: 7T CMR scans were performed on 10 healthy volunteers on whole-body research MRI scanner (Siemens Healthcare, Erlangen, Germany) with 8 channel Tx/32 channel Rx cardiac coil (MRI Tools GmbH, Berlin, Germany) under institutional review board approval. Vectorcardiogram ECG was successfully performed using a learning phase outside of the magnetic field, with a trigger algorithm with sufficient accuracy for CMR despite severe ECG signal distortions from the 7T field. Cine CMR was performed after 3rd-order B0 shimming using a high-resolution breath-held ECG-retro-gated segmented two-dimensional spoiled gradient echo sequence, and 2-dimensional phase contrast flow imaging. Analysis was performed using Cmr42 software (Circle CVi, Calgary). Results: Successful 7T CMR scans were acquired in all patients (100%) using the Vectorcardiogram 3-lead ECG method. Image quality was sufficient to quantitate both left and right ventricular volumes, ejection fraction, aortic and pulmonary blood flow and regurgitant fractions in 9/10 (90%) of volunteers (figure 1), with one volunteer having difficulty with breath-holding and ventricular ectopy causing gating artefacts.
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View more >Background: Ultra-high-field (B0 ≥7 Tesla) cardiovascular magnetic resonance (CMR) offers increased resolution, but cardiac imaging requiring ECG gating is significantly impacted from the magneto-hydrodynamic (MHD) effect, distorts the ECG trace (1–3). Previously, 7T CMR was constrained to using pulse oximetry for triggering, We explored the technical feasbility of a 7 T research MR scanner using of-the-art ECG trigger algorithm to assess left and right ventricular volumes, aortic and pulmonary valve flow. Methods: 7T CMR scans were performed on 10 healthy volunteers on whole-body research MRI scanner (Siemens Healthcare, Erlangen, Germany) with 8 channel Tx/32 channel Rx cardiac coil (MRI Tools GmbH, Berlin, Germany) under institutional review board approval. Vectorcardiogram ECG was successfully performed using a learning phase outside of the magnetic field, with a trigger algorithm with sufficient accuracy for CMR despite severe ECG signal distortions from the 7T field. Cine CMR was performed after 3rd-order B0 shimming using a high-resolution breath-held ECG-retro-gated segmented two-dimensional spoiled gradient echo sequence, and 2-dimensional phase contrast flow imaging. Analysis was performed using Cmr42 software (Circle CVi, Calgary). Results: Successful 7T CMR scans were acquired in all patients (100%) using the Vectorcardiogram 3-lead ECG method. Image quality was sufficient to quantitate both left and right ventricular volumes, ejection fraction, aortic and pulmonary blood flow and regurgitant fractions in 9/10 (90%) of volunteers (figure 1), with one volunteer having difficulty with breath-holding and ventricular ectopy causing gating artefacts.
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Conference Title
European Heart Journal
Volume
39
Issue
suppl_1
Subject
Cardiovascular medicine and haematology
Clinical sciences
Science & Technology
Life Sciences & Biomedicine
Cardiac & Cardiovascular Systems
Cardiovascular System & Cardiology