Fig. 8. Examples of 4D flow cardiac magnetic resonance visualization techniques, demonstrated on intracardiac flow data acquired in healthy volunteer.

In these examples, flow visualization is overlaid onto 2D bSSFP acquisition in three-chamber view.

A. Pathlines are trajectories that massless fluid particles would follow through dynamic velocity field and are suitable for studies of path of pulsatile blood flow over time. Here, transit of blood through left ventricle (LV) is shown by pathlines emitted from mitral valve at time point of peak A-wave and traced to time point of early systole. Timing of ECG is included for reference. B-D. Streamlines are instantaneously tangential to velocity vector field and are useful for visualizing 3D velocity fields at discrete time points. Here, streamlines generated in long-axis plane show parts of intracardiac velocity field at time points of peak early filling (E-wave) (B), peak late filling (A-wave) (C), and peak systole (D). Adapted from Dyverfeldt et al. J Cardiovasc Magn Reson 2015;17:72 (30).