Hydrodynamic characterisation of ventricular assist devices

Area of Science:

• Biomedical Engineering
• Cardiovascular Technology

Background:

• Ventricular assist devices (VADs) are crucial for heart failure management.
• Accurate characterization of VAD hydraulic performance is essential for device development and clinical application.

Purpose of the Study:

• To design and validate a novel mock circulatory system (MCS) for evaluating VAD hydraulic performance.
• To assess the influence of preload, afterload, and test fluid on VAD function using the developed MCS.

Main Methods:

• A new MCS was constructed with adjustable compliance and resistance, incorporating a preload and afterload section.
• The MCS was validated using a pulse duplicator system, measuring pressure and flow under diverse afterload conditions.
• The Medos VAD was tested using the MCS with water and pig blood at various settings and pump rates.

Main Results:

• The MCS accurately simulated hemodynamic conditions and its performance fit a 4-element electrical analogon.
• Device-specific pump function graphs were generated for the Medos VAD using different test fluids.
• Flow was demonstrated to be sensitive to changes in preload and afterload conditions.

Conclusions:

• The developed MCS is a valuable tool for characterizing the hydraulic performance of VADs.
• The study highlights the significant impact of preload, afterload, and test fluid properties on VAD hemodynamic performance.
• This system facilitates a deeper understanding of VAD function for improved device design and patient outcomes.