Platelet adhesion emulation: A novel method for estimating the device thrombosis potential of a ventricular assist device

Abstract

Device thrombosis inside ventricular assist devices remains a limitation to their long-term clinical use. Thrombosis potential exists in almost all ventricular assist devices because the device-induced high shear stress and vortices can activate platelets, which then aggregate and adhere to the surfaces inside the ventricular assist device. To decrease the device thrombosis potential of long-term use of ventricular assist devices, a methodology entitled platelet adhesion emulation for predicting the thrombosis potential and thrombosis position inside the ventricular assist devices is developed. The platelet adhesion emulation methodology combines numerical simulations with in vitro experiments by correlating the structure of the flow passage components within the ventricular assist device with the platelet adhesion to estimate the thrombosis potential and location, with the goal of developing ventricular assist devices with optimized antithrombotic performance. Platelet adhesion emulation is aimed at decreasing the device thrombus potential of ventricular assist devices. The platelet adhesion emulation effectiveness is validated by simulating and testing an axial left ventricular assist device. The blood velocity relative to the surfaces of the flow passage components is calculated to estimate the platelet adhesion potential, indicating the probability of thrombus formation on the surfaces. Platelet adhesion emulation experiments conducted in a mock circulation loop with pump prototypes show the distribution of platelet adhesion on the surfaces. This methodology of emulating the device thrombosis distribution indicates the potential for improving the component structure and reducing the device thrombosis of ventricular assist devices.

A 3‐dimensional‐printed left ventricle model incorporated into a mock circulatory loop to investigate hemodynamics inside a severely failing ventricle supported by a blood pump

“…We built an experimental MCL to imitate the pulsatile heart and systemic circulation. The 3D‐printed LV and axial flow pump LAP31 28 were connected to this MCL. The whole MCL consisted of a 3D‐printed silicone LV within an acrylic reservoir, electric drive motor, aortic valve, mitral valve, polyvinyl chloride (PVC) tubes to imitate the blood vessels and the assisted axial blood pump LAP31.…”

“…The whole MCL consisted of a 3D‐printed silicone LV within an acrylic reservoir, electric drive motor, aortic valve, mitral valve, polyvinyl chloride (PVC) tubes to imitate the blood vessels and the assisted axial blood pump LAP31. The loop was filled with a 40% glycerin solution and aluminum oxide particles to match the human blood viscosity of 3.5 × 10 −3 Pa·s 28 …”

A two-phase flow approach for modeling blood stasis and estimating the thrombosis potential of a ventricular assist device

“…This work investigated the Fuwai LAP31 axial blood pump. Liu et al 35 conducted a particle adhesion and deposition experiment using fluorescent particles, to simulate platelet adhesion on the blood flow surfaces inside the LAP31 axial blood pump. The flowrate was 3 L/min, with a rotational speed of 9000 rpm.…”

“…Prior to the particle adhesion and deposition experiment, a set of hydraulic experiments were also conducted, with flow rates ranging from 1 L/min to 3 L/min, and a rotational speed of 10,000 rpm. 35…”

“…Liu et al 35 proposed an experimental methodology to emulate platelet adhesion emulation for predicting the thrombosis potential and thrombosis position inside the VAD. Fluorescent particles were employed.…”