A Multiphysics Biventricular Cardiac Model: Simulations With a Left-Ventricular Assist Device.

Area of Science:

• Biomedical Engineering
• Computational Mechanics
• Cardiovascular Physiology

Background:

• Computational models are crucial for predicting medical device performance before clinical trials.
• Left-ventricular assist devices (LVADs) require sophisticated modeling to understand heart-device interactions.
• Simulating cardiac function and hemodynamics is complex due to multi-physics coupling.

Purpose of the Study:

• To develop and validate a fully-coupled finite element model for simulating heart-LVAD interaction.
• To investigate the hemodynamic and mechanical consequences of LVAD implantation on a failing heart.
• To assess the model's capability in predicting adverse events like ventricular collapse.

Main Methods:

• A finite element model integrated electrical activation, myocardial mechanics, and blood hemodynamics.
• The model used an idealized biventricular geometry with a simplified Purkinje network for electrical activation.
• LVAD insertion was simulated with a continuous flow cannula, and a proportional controller managed pump speed.

Main Results:

• The model predicted a shift in the left ventricular (LV) pressure-volume loop shape post-LVAD insertion.
• Increased pump speeds led to cessation of aortic ejection and LV decompression.
• The simulation successfully predicted LV cavity collapse, a critical adverse event.

Conclusions:

• The developed computational model accurately predicts heart-LVAD interactions and potential complications.
• This model serves as a valuable tool for pre-clinical testing of LVADs and control systems.
• It can aid in designing strategies to prevent LV collapse in recipients.