Magnetic-resonance (MR) phase velocity mapping (PVM) shows promise in measuring the mitral regurgitant volume. However, in its conventional nonsegmented form, MR-PVM is slow and impractical for clinical use. The aim of this study was to evaluate the accuracy of rapid, segmented k-spaceMR-PVM in quantifying the mitral regurgitant flow through a control volume (CV) method. Two segmented MR-PVM schemes, one with seven (seg-7) and one with nine (seg-9) lines per segment, were evaluated in acrylic regurgitant mitral valve models under steady and pulsatile flow. A nonsegmented (nonseg) MR-PVM acquisition was also performed for reference. The segmented acquisitions were considerably faster (min) than the nonsegmented (>45 min). The regurgitant flow rates and volumes measured with segmented MR-PVM agreed closely with those measured with nonsegmented MR-PVM (differences 0.05), when the CV was large enough to exclude the region of flow acceleration and aliasing from its boundaries. The regurgitant orifice shape (circular vs. slit-like) and the presence of aortic outflow did not significantly affect the accuracy of the results under both steady and pulsatile flow (p>0.05). This study shows that segmented k-space MR-PVM canaccurately quantify the flow through regurgitant orifices using the CV method and demonstrates great clinical potential.
Fast Measurements of Flow Through Mitral Regurgitant Orifices With Magnetic Resonance Phase Velocity MappingAnnals of Biomedical Engineering
Publisher's StatementThe final publication is available at Springer via http://dx.doi.org/10.1007/s10439-004-7815-4
Citation InformationZhang, H., Halliburton, S. S., White, R. D., , & Chatzimavroudis, G. P. (2004). Fast Measurements of Flow through Mitral Regurgitant Orifices with Magnetic Resonance Phase Velocity Mapping. Annals of Biomedical Engineering, 32(12), 1618 - 1627. doi:10.1007/s10439-004-7815-4