Exploring the influence of parametrized pulsatility on left ventricular washout under LVAD support: a computational...

Area of Science:

• Biomedical Engineering
• Cardiovascular Flow Dynamics
• Computational Fluid Dynamics

Background:

• Pulsatility in left ventricular assist devices (LVADs) is recognized for its potential to mitigate complications like blood stagnation and thrombosis.
• Determining the optimal pulsatile waveform for LVADs remains an active area of research, crucial for enhancing hemocompatibility and device efficacy.

Purpose of the Study:

• To develop and apply a computational framework for systematically quantifying the impact of parametrized pulsatility on washout within a left ventricle.
• To investigate the effects of different pulsatile flow rate parameters on the efficiency of ventricular washout.

Main Methods:

• A framework integrating parametrized full-order simulations, reduced-order models, and sensitivity analysis was employed.
• An idealized 2D left ventricle model was used with a parametrized sinusoidal LVAD flow rate to simulate washout dynamics.
• The framework enabled significant computational speed-ups in the sensitivity analysis process.

Main Results:

• The study identified that short, intense pulsatile flows provide the most effective washout in the idealized left ventricle.
• The duration between consecutive pulses was found to have a negligible impact on the overall washout efficiency.
• The developed framework demonstrated efficiency gains proportional to the number of samples needed for sensitivity analysis.

Conclusions:

• The findings suggest that optimizing pulse characteristics, specifically intensity and duration, is key for improving LVAD performance in terms of washout.
• This research provides a systematic approach to analyzing pulsatility effects, offering valuable insights for the design of next-generation LVADs.
• The computational framework presented can accelerate the optimization process for LVAD flow dynamics.