In vitro evaluation of multiobjective hemodynamic control of a heart-assist pump

Area of Science:

• Biomedical Engineering
• Cardiovascular Physiology

Background:

• End-stage heart failure necessitates advanced ventricular assist devices (VADs).
• Effective VADs require responsive hemodynamic control to adapt to physiological changes.
• Current VAD control strategies face challenges in balancing perfusion and device safety.

Purpose of the Study:

• To develop and evaluate a novel multiobjective control algorithm for VADs.
• To optimize hemodynamic management by balancing optimal perfusion and avoiding ventricular suction.
• To enhance VAD performance and patient quality of life through improved control.

Main Methods:

• Implemented an in vitro optimal control strategy combining venous return and suction prevalence indices.
• Derived indices from diastolic flow derivative and flow signal harmonic spectra.
• Utilized a state estimator based on actuator back-electromotive force (back-EMF) to eliminate flow sensors.
• Evaluated controller responsiveness in a mock circulatory simulator with a HeartQuest centrifugal blood pump.

Main Results:

• The multiobjective algorithm demonstrated robust performance in response to preload and afterload variations.
• The developed controller effectively balanced competing objectives of perfusion and suction avoidance.
• Performance was superior compared to controllers using individual indices.

Conclusions:

• The novel multiobjective control algorithm offers improved hemodynamic management for VADs.
• This approach enhances VAD reliability and responsiveness, crucial for end-stage heart failure treatment.
• The sensorless state estimator and combined control strategy represent a significant advancement in VAD technology.