Design of a Hydrodynamic Performance Bench for Ventricular Assist Devices

Abstract

This work presents the design of a hydrodynamic performance bench (HPB) of Ventricular Assist Devices (VADs) for evaluations of developed prototypes. VADs are used for the treatment of patients with Congestive Heart Failure (CHF), either as a bridge to recovery, for transplantation or as destination therapy. HPB is required for the performance evaluation of VADs that are under development in Brazil. The performance evaluation of a VAD considers the rotation speed [rpm], flow rate [L/min], pressure [mmHg] and power [W]. The project consists in choosing an actuator and transducers from HPB, and developing the mechanical components, supervisory control and modules. The HPB mechanical components were designed in SolidWorks® following rapid prototyping and built by additive manufacturing. The HPB supervisory program was developed in graphic language through the Labview® program and implemented in a development and application platform with data acquisition system. The manipulated variable of the supervisory system is the motor speed [rpm] acting via an Escon 50/4 EC-S power controller on the BLDC EC45 N339281 motor. The controlled variable is the “VAD flow” [L/min] provided by an HT-110 flow transducer. A particle image velocimetry (PIV) module was developed for flow analysis. All process data are stored in spreadsheets for later consultation. HPB could assist in a satisfactory way in the analysis of the developed VADs prototypes, demonstrating the technical success of the project.

Embedded Cyber-Physical System for Physiological Control of Ventricular Assist Devices

“…However, in this case, the MOPC-EIS shows an advantage in accuracy with two fewer points outside the 5% error range and smaller error values, while the MOPC-PC shows a slight tendency to overestimate the flow. The percentage error of the flow estimator was 3.33 ± 0.92%, in agreement with Leao et al [28] and other estimators [30][31][32][33][34][35][36][37][38][39][40][41][42]. The percentage error of the differential pressure estimator was 1.93 ± 0.7%, in agreement with Leao et al [28] and other estimators.…”

“…However, on the other hand, in vitro testing presents significantly more complex adversities than those that may be encountered in a virtual environment. Therefore, the error obtained in the proposal of this study can be considered satisfactory considering the specialized literature in this field [30][31][32][33][34][35][36][37][38][39][40][41][42]. Nevertheless, in vivo testing also presents even higher levels of complexity that cannot be replicated in an in vitro study, and new studies under these conditions will always be necessary.…”

“…The performance evaluation was conducted using a previously documented mock loop system [34] with a prototype LVAD (VAD-MLS) as shown in Figure 2. The system includes a 5-liter acrylic reservoir and 3/8" silicone tubing connected to the VAD prototype.…”

Embedded Cyber-physical System for Physiological Control of Ventricular Assist Devices

“…The performance assessment was conducted using a previously documented mock loop system [31] with an LVAD prototype (VAD-MLS), as illustrated in Figure 2 The manipulated variable of the supervisory system is the motor speed (rpm), controlled by an Escon 50/4 EC-S power controller (Maxon Motor, Sachseln, Switzerland), coupled with an EC45 N339281 BLDC motor (Maxon Motor, Sachseln, Switzerland). The VAD flow (L/min), the controlled variable, is measured by an HT-110 flow transducer (Transonic Systems, Ithaca, USA).…”