Embedded Computational Heart Model for External Ventricular Assist Device Investigations.

Area of Science:

• Computational modeling
• Biomedical engineering
• Cardiovascular research

Background:

• External cardiac assist devices offer a promising approach to heart failure treatment.
• Designing these devices is complex, necessitating advanced computational tools.
• A structured approach combining experiments and computer-based optimization is crucial.

Purpose of the Study:

• To present a computational modeling framework for simulating heart tissue structure, electrophysiology, and actuation.
• To enable the study of healthy and pathological hearts, including the effects of external assist devices.
• To provide a tool for computer-based optimization in the design of cardiac assist devices.

Main Methods:

• Developed a computational framework incorporating nonlinear anisotropic material laws for passive tissue and an orthotropic active-strain model for muscle contraction.
• Initiated muscle contraction via a periodically propagating electrical potential.
• Coupled the heart model with a circulation network and incorporated boundary conditions for external assist devices at the epicardium.

Main Results:

• Simulated results accurately reproduced deformations in healthy and pathological heart models compared to measurements.
• Cardiac output and ventricular pressure signals showed good agreement with expected values.
• Demonstrated that external actuation, such as cardiac patches, can restore healthy blood flow in a pathological model.

Conclusions:

• The computational framework accurately predicts characteristic heart dynamics, including apex shortening, wall thickening, and twisting.
• The model is effective for studying pathological hearts and the impact of external activation.
• This framework supports the design and optimization of external cardiac assist devices for heart failure treatment.