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166 8. TOWARDS THE REAL-TIME MODELING OF THE HEART

FIG. 8.26 Dirichlet boundary conditions applied to the biventricle heart model.

TABLE 8.5 Ventricular Pressure of the Biventricle Model
Pressure (kPa) References
Left ventricular pressure (LVP) 1.5 [94–96]
Right ventricular pressure (RVP) 1 [95, 96]

TABLE 8.6 Passive Material Parameters
A (kPa) a 1 a 2 a 3 a 4 a 5 a 6
0.19 12.70 8.36 8.56 11.22 14.25 9.15

TABLE 8.7 BV With Different Mesh Discretizations
Models BV-1 BV-2 BV-3 BV-R

Nodes 882 902 922 912

Secondly, perturbations are applied to mesh configurations BV-1, BV-2, and BV-3 such that the geometrical shape of
the three hearts can be varied. The geometrical perturbation is kept minor as it is expected that, in a realistic scenario,
the heart datasets selected from the database would have similar features and characteristics such as age, gender, fit-
ness, diseases, etc. The applied perturbation is a result of two forms of transformation, namely rotation and scaling.
A total of nine unique hearts are produced, with one of them illustrated in Fig. 8.27. In order to build a single para-
metric database, each of these nine heart models is then assigned to a unique stress scaling coefficient value, A (Eq. 8.1),
within the range of 0.04kPa A 0.22kPa.
Lastly, the shape of the problem that needs to be solved, BV-R, is also altered as shown in Fig. 8.28 and a stress-
scaling factor of A ¼ 0.13 is assigned.
Following the dataset standardization, which will be elaborated up on in more detail in Sections 8.5.2.1 and 8.5.2.2,
the actual PODI computation considering a targeted energy level of 99% is analog to the approach presented in

I. BIOMECHANICS