Automatic mapping of atrial fiber orientations for patient‐specific modeling of cardiac electromechanics using image registration

Figures

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  Figure 1. Processing pipeline for the registration and fiber estimation for the patients' atria

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  Figure 2. Fiber direction of atlas atria. The colors represent the regions with different fiber directions

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  Figure 3. A, The landmarks defined on the atlas atria. B, The binary image of the atlas

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  Figure 4. Atlas atria (blue) and patient's atria (yellow) at different steps of the registration process: A, meshed geometry after affine transformation; B, binary images after registration; and C, the meshed geometry after the registration and interpolation to the tetrahedral nodes

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  Figure 5. Patient 1 fibers. A, Defined fiber orientations in patient 1. B, Mapped fiber orientation in patient 1. C, Difference in fiber direction between defined and mapped fiber orientation. The difference is calculated as err=1−|fmappedTfdefined|

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  Figure 6. Atlas fibers. Difference in fiber direction between defined and mapped fiber orientation

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  Figure 7. Results of electrophysiology simulations. Activation times of patient 1 atria and atlas atria with mapped fibers and defined fibers and activation time differences. The difference is calculated as diff = |(activation time)mapped − (activation time)defined|. A, Activation time with mapped fibers for patient 1. B, Activation time with defined fibers for patient 1. C, Difference between the activation times with mapped fibers to defined fibers of Patient 1. D, Activation time with mapped fibers for the atlas. E, Activation time with defined fibers for the atlas. F, Difference between the activation times with mapped fibers to defined fibers of the atlas atria

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  Figure 8. Deformation difference between mapped and defined fibers in the atria for patient 1 at the time of maximal contraction of the left atrium (time = 0.31 s). A,B, Displacement of the atria for mapped and defined fibers. C,D, Slices through the right and left atrium in the plane shown in Figure 10A,B, respectively. The black contour shows the atrium in the relaxed state, the green contour shows the contracted atria with defined fibers, and the red contour line shows the contracted atria with mapped fibers

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  Figure 9. Deformation difference between mapped and defined fibers in the atria for the atlas atria at the time of maximal contraction of the left atrium (time = 0.35 s). A,B, Displacement of the atria for mapped and defined fibers. C,D, Slices through the right and left atrium in the plane shown in Figure 10A,B, respectively. The black contour shows the atrium in the relaxed state, the green contour shows the contracted atria with defined fibers, and the red contour line shows the contracted atria with mapped fibers

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  Figure 10. Illustrating the slices through the atria which are used to show the contraction. A, Slice through the atria in the plane of the four‐chamber view. B, Slice through the atria in a plane parallel to the heart skeleton

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  Figure 11. Volume (V) and pressure (p) curves plotted over time of the right (R) and left (L) atrium of patient 1 and the atlas geometry for mapped fibers (map) and defined fibers (def)

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  Figure 12. Volume of active contracting tissue over time for the atlas atria with defined and mapped fibers