Biofunctionalization of surfaces to minimize undesirable effects in cardiovascular assistance devices.

Background: The reactivity of blood with non-endothelial surface is a challenge for long-term Ventricular Assist Devices development, usually made with pure titanium, which despite of being inert, low density and high mechanical resistance it does not avoid the thrombogenic responses. Here we tested a modification on the titanium surface with Laser Induced Periodic Surface Structures followed by Diamond Like Carbon (DLC) coating in different thicknesses to customize the wettability profile by changing the surface energy of the titanium.

Methods: Four different surfaces were proposed: (1) Pure Titanium as Reference Material (RM), (2) Textured as Test Sample (TS), (3) Textured with DLC 0.

Apical aortic blood pump preclinical assessment for long-term use: Durability test and stator topology to reduce wear in the bearing system.

This study presents an assessment for long-term use of the apical aortic blood pump (AABP), focusing on wear reduction in the bearing system. AABP is a centrifugal left ventricle assist device initially developed for bridge to transplant application. To analyze AABP performance in long-term applications, a durability test was performed.

A strategy for designing of customized electromechanical actuators of blood pumps.

Congestive heart failure is a pathology of global incidence that affects millions of people worldwide. When the heart weakens and fails to pump blood at physiological rates commensurate with the requirements of tissues, two main alternatives are cardiac transplant and ventricular assist devices (VADs). This article presents the design strategy for development of a customized VAD electromagnetic actuator.

A system to help physicians with fracture detection in stents.

Fractures in stents are usually detected by visual analysis, which may be affected by the presence of noise and image deformations. The lack of research into automating stent fracture detection has motivated this work, in which techniques are developed to facilitate diagnosis by observation (Image Delineation Algorithm) and, when possible, to point out areas of possible fractures (Fracture Detection Algorithm). The use of classical elements and the development of additional computational techniques contributed to the process of image analysis, providing a possible way to aid medical diagnosis.

An electro-fluid-dynamic simulator for the cardiovascular system.

This work presents the initial studies and the proposal for a cardiovascular system electro-fluid-dynamic simulator to be applied in the development of left ventricular assist devices (LVADs). The simulator, which is being developed at University Sao Judas Tadeu and at Institute Dante Pazzanese of Cardiology, is composed of three modules: (i) an electrical analog model of the cardiovascular system operating in the PSpice electrical simulator environment; (ii) an electronic controller, based on laboratory virtual instrumentation engineering workbench (LabVIEW) acquisition and control tool, which will act over the physical simulator; and (iii) the physical simulator: a fluid-dynamic equipment composed of pneumatic actuators and compliance tubes for the simulation of active cardiac chambers and big vessels. The physical simulator (iii) is based on results obtained from the electrical analog model (i) and physiological parameters.

Magnetic suspension of the rotor of a ventricular assist device of mixed flow type.

This work presents results of preliminary studies concerning application of magnetic bearing in a ventricular assist device (VAD) being developed by Dante Pazzanese Institute of Cardiology-IDPC (São Paulo, Brazil). The VAD-IDPC has a novel architecture that distinguishes from other known VADs. In this, the rotor has a conical geometry with spiral impellers, showing characteristics that are intermediate between a centrifugal VAD and an axial VAD.

Spiral blood pump: conception, development and clinical application of the original project.

Introduction: This paper addresses an original project that encompasses the conception, development and clinical application of a helical bypass pump called the Spiral Pump, that uses the association of centrifugal and axial propulsion forces based de the Archimedes principle. This project has obtained a Brazilian Patent and an International Preliminary Report, defining it as an invention.

Methods: The aim of this work was to evaluate the hemodynamic capacity and the impact of its application on blood cells by means of experimental in vitro tests, including hydrodynamic efficiency, effect on hemolysis and flow visualization.

Hemolysis in an electromechanical driven pulsatile total artificial heart.

A motor rotation in an electromechanically-driven pulsatile total artificial heart (TAH) may influence hemolysis. This study is designed to evaluate motor rotational conditions of the TAH and choose a suitable condition to obtain the least hemolytic characteristics. The TAH was driven in two motor rotational conditions: a constant motor rotational speed (rpm) mode (mode A) and a gradually increasing rpm mode (mode B).