Fig. 1.

A Target systolic motion. The images represent the motion of a slice of the patient’s heart during systole as computed by the motion tracking algorithm (blue moving geometry). The grey geometry represents the ED geometry. B Epicardial displacement. The images show the distribution of the displacement of the epicardium normal to the surface during systole in an anterior (top row), posterior (middle row) and bottom (bottom row) view. C Penalty map. The figure shows the anterior, posterior and bottom view of the penalty map for the displacement normal to the surface applied on the epicardium of the ventricles to model the effect of the pericardium on the ventricles. D Apex to base epicardial displacement. The plot shows the epicardial displacement normal to the surface against the apico-basal direction (0 at the base and 1 at the apex). The black line shows the average trend, while the gray area shows the standard deviation. E Apex to base normalised epicardial displacement. The plot shows the epicardial displacement normal to the surface normalised between 0 and 1, together with the function we used to define the scale for the spring stiffness (red line). F Apex to base penalty map. The plot shows the penalty scale we derived from the data against the apico-basal direction. The function was computed by flipping the red curve shown in panel E. Epicardial regions with low and high displacement normal to the surface were applied with maximum and minimum penalty, respectively.