In vitro performance of trans-valve left ventricular assist device installed at aortic valve position

Area of Science:

• Biomedical Engineering
• Cardiovascular Devices
• Medical Technology

Background:

• Heart failure necessitates advanced circulatory support.
• Existing left ventricular assist devices (LVADs) often lack pulsatility.
• A need exists for integrated devices that combine pumping and valvular function.

Purpose of the Study:

• To develop and evaluate a novel trans-valve left ventricular assist device (LVAD).
• To integrate an axial-flow blood pump with a polymer membrane valve.
• To assess the hemodynamic performance and unloading effect of the device in a mock circulation.

Main Methods:

• A rear-impeller axial-flow blood pump (AFBP) was designed with a polymer membrane valve at the aortic position.
• The trans-valve LVAD was tested in a mock circulation simulating the left ventricle (LV) using a pulsatile flow VAD.
• Hemodynamic parameters including aortic flow, pressure, and LV unloading were measured at varying motor speeds.

Main Results:

• Increasing motor speed to 26,400 rpm increased mean aortic flow (4.2 to 5.3 L/min) and mean aortic pressure (83.4 to 100 mm Hg).
• The device achieved a significant unloading effect on the LV, reducing motor current by 21%.
• Energy equivalent pressure increased, while surplus hemodynamic energy decreased by 15.4%.

Conclusions:

• The trans-valve LVAD effectively supports the left ventricle while preserving pulsatility.
• The integrated design offers a novel and promising approach to LV support without complex mechanisms.
• This device represents a significant advancement in the field of mechanical circulatory support.