The Vienna implantable centrifugal blood pump

Area of Science:

• Biomedical Engineering
• Cardiovascular Devices
• Fluid Dynamics

Background:

• Rotary pumps are increasingly favored over membrane pumps for implantable devices due to biocompatibility improvements.
• Key challenges include minimizing shear stress, blood traumatization, and optimizing seal design for long-term function.
• Developing effective control strategies is crucial for physiological adaptation and patient outcomes.

Purpose of the Study:

• To develop and evaluate an implantable impeller pump with minimized hemolysis and thrombus formation.
• To investigate advanced control strategies for physiological adaptation during nonpulsatile support.
• To assess the efficacy of different evaluation methods for implantable blood pumps.

Main Methods:

• Numerical simulation and visualization were used to optimize pump geometry.
• In vitro blood evaluation was employed as the primary method for assessing pump performance.
• Development and testing of a controller based on nonlinear and fuzzy logic strategies.
• Computer simulation was used to evaluate cardiac contractility during nonpulsatile support.

Main Results:

• Optimized pump geometry achieved low hemolysis rates: in vitro IH = 0.008, MIH = 0.58.
• In vivo hemolysis was measured at 2.1 to 3 mg% plasma-free hemoglobin.
• A robust controller integrating nonlinear and fuzzy logic was successfully developed.
• In vitro blood evaluation demonstrated superior effectiveness for pump assessment.

Conclusions:

• The developed implantable impeller pump shows promising results in minimizing blood damage.
• Advanced control strategies are essential for effective physiological adaptation in cardiac support.
• In vitro blood evaluation is a critical tool for the development and validation of blood pumps.
• This research provides a comprehensive overview of pump and controller design evaluation methods.