Concept, Design, and Early Prototyping of a Low-Cost, Minimally Invasive, Fully Implantable Left Ventricular Assist Device

Abstract

Despite evidence associating the use of mechanical circulatory support (MCS) devices with increased survival and quality of life in patients with advanced heart failure (HF), significant complications and high costs limit their clinical use. We aimed to design an innovative MCS device to address three important needs: low cost, minimally invasive implantation techniques, and low risk of infection. We used mathematical modeling to calculate the pump characteristics to deliver variable flows at different pump diameters, turbomachinery design software CFturbo (2020 R2.4 CFturbo GmbH, Dresden, Germany) to create the conceptual design of the pump, computational fluid dynamics analysis with Solidworks Flow Simulation to in silico test pump performance, Solidworks (Dassault Systèmes SolidWorks Corporation, Waltham, MA, USA) to further refine the design, 3D printing with polycarbonate filament for the initial prototype, and a stereolithography printer (Form 2, Formlabs, Somerville, MA, USA) for the second variant materialization. We present the concept, design, and early prototyping of a low-cost, minimally invasive, fully implantable in a subcutaneous pocket MCS device for long-term use and partial support in patients with advanced HF which unloads the left heart into the arterial system containing a rim-driven, hubless axial-flow pump and the wireless transmission of energy. We describe a low-cost, fully implantable, low-invasive, wireless power transmission left ventricular assist device that has the potential to address patients with advanced HF with higher impact, especially in developing countries. In vitro testing will provide input for further optimization of the device before proceeding to a completely functional prototype that can be implanted in animals.

Innovative Implantable Left Ventricular Assist Device—Performance under Various Resistances and Operating Frequency Conditions

“…These pumps can be divided into axial [32,33] and centrifugal, where axial pumps are much smaller. In order to achieve the required pressure increments, axial pumps require significant angular velocities [34], which leads to unfavorable phenomena, i.e., thrombosis (blood clot formation at the bloodpump contact surface) [2,35] and hemolysis [36,37] phenomena. What is more, thrombosis may occur in any component of the pump and may lead, for instance, to higher power consumption.…”

Effect of Vascular Lumen Reduction on the Performance and Energy Consumption of an Innovative Implantable LVAD

“…Continuous flow pumps are further categorized into axial and centrifugal pumps. While axial pumps are smaller in size, they require considerably higher rotational speeds compared to centrifugal pumps [25], which may lead to thrombosis [5,26] and hemolysis [27,28]. However, by optimizing the shape of the axial pump, the necessary rotational speed can be reduced for the same pressure increase [29].…”

“…Another example would be a continuous-flow total artificial heart that operates without valves and is suspended both axially and radially through the balancing of the magnetic and hydrodynamic forces to improve biocompatibility [32]. Yet another example is a low-cost device for long-term use containing a rim-driven, hubless, axial flow pump, as well as the wireless transmission of energy [25].…”