Pulsatile Physiological Control of Blood Pump-Cardiovascular System Based on Feedforward Compensation

Area of Science:

• Biomedical Engineering
• Cardiovascular Engineering
• Control Systems

Background:

• Rotary Blood Pumps (RBPs) are crucial ventricular assist devices.
• Constant speed operation reduces blood flow pulsatility, causing adverse effects.
• Restoring pulsatility is key to improving RBP function and patient outcomes.

Purpose of the Study:

• To design and evaluate a pulsatile physiological control algorithm with feed-forward compensation (FFC) for RBPs.
• To improve real-time regulation of rotational speed for accurate pulsatile blood flow output.
• To enhance ventricular unloading and pulsatile performance compared to existing methods.

Main Methods:

• Developed a coupled model of the RBP and cardiovascular system (CVS) in SIMULINK.
• Designed a control algorithm combining FFC-based pulsatile control and an anti-reflux algorithm.
• Implemented adaptive switching between control strategies based on pump flow rate thresholds.
• Validated the system through simulations and extracorporeal circulation experiments.

Main Results:

• FFC reduced pulsatile physiological control tracking error by 80%.
• The system demonstrated rapid and stable tracking during a 50% physiological parameter change, preventing reflux.
• Achieved a 30 mmHg increase in aortic beat-to-beat differential pressure in experiments.
• Superior pulsatile and ventricular unloading performance compared to non-FFC and constant-speed controls.

Conclusions:

• The FFC-based pulsatile physiological control effectively restores blood flow pulsatility in RBPs.
• This control strategy significantly improves RBP performance and ventricular unloading.
• The developed method offers a promising advancement for RBP technology and patient care.