Material parameter identification for modelling the left ventricle in the healthy state

An idealized truncated ellipsoidal model, was used to simulate a healthy canine left ventricle. Passive behaviour of the myocardium was modelled using the constitutive model of Usyk. In addition, active behaviour of the myocardium was modelled by the active stress law of Guccione. Furthermore, the load faced by the left ventricle in ejecting blood into the arterial system, was modelled with the three element Windkessel model of Westerhof. The model was calibrated to pressure-volume data, which was adaptedfrom the work of Kerckhoffs. The projected Levenberg-Marquardt algorithm was used to identify material parameters. Identification of the anisotropic constants in the model of Usyk proved to be difficult, with the calibration algorithm often converging to parameter values that produced numerical instability. An idealized truncated ellipsoidal model, was used to simulate a healthy canine left ventricle. Passive behaviour of the myocardium was modelled using the constitutive model of Usyk. In addition, active behaviour of the myocardium was modelled by theactive stress law of Guccione. Furthermore, the load faced by the left ventricle in ejecting blood into the arterial system, was modelled with the three element Windkessel model of Westerhof. The model was calibrated to pressure-volume data, which was adapted from the work of Kerckhoffs. The projected Levenberg-Marquardt algorithm was used to identify material parameters. Identification of the anisotropic constants in the model of Usyk proved to be difficult, with the calibration algorithm often converging to parameter values that produced numerical instability. An idealized truncated ellipsoidal model, was used to simulate a healthy canine left ventricle. Passive behaviour of the myocardium was modelled using the constitutive model of Usyk. In addition, active behaviour of the myocardium was modelled by the active stress law of Guccione. Furthermore, the load faced by the left ventricle in ejecting blood into the arterial system, was modelled with the three element Windkessel model of Westerhof. The model was calibrated to pressure-volume data, which was adaptedfrom the work of Kerckhoffs. The projected Levenberg-Marquardt algorithm was used to identify material parameters. Identification of the anisotropic constants in the model of Usyk proved to be difficult, with the calibration algorithm often converging to parameter values that produced numerical instability. An idealized truncated ellipsoidal model, was used to simulate a healthy canine left ventricle. Passive behaviour of the myocardium was modelled using the constitutive model of Usyk. In addition, active behaviour of the myocardium was modelled by the active stress law of Guccione. Furthermore, the load faced by the left ventricle in ejecting blood into the arterial system, was modelled with the three element Windkessel model of Westerhof. The model was calibrated to pressure-volume data, which was adapted from the work of Kerckhoffs. The projected Levenberg-Marquardt algorithm was used to identify material parameters. Identification of the anisotropic constants in the model of Usyk proved to be difficult, with the calibration algorithm often converging to parameter values that produced numerical instability.

Grantor dc:publisher.institution

Department of Civil Engineering

Year dc:date.issued

2014

Author dc:creator

• Essack, Mohammed Asaad

Advisor dc:contributor.advisor

• Skatulla, Sebastian

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/8680

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/8680