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arXiv · 1511.01357

In Vitro Durability - Pivot bearing with Diamond Like Carbon for Ventricular Assist Devices

Abstract

Institute Dante Pazzanese of Cardiology (IDPC) develops Ventricular Assist Devices (VAD) that can stabilize the hemodynamics of patients with severe heart failure before, during and/or after the medical practice; can be temporary or permanent. The ADV's centrifugal basically consist of a rotor suspended for system pivoting bearing; the PIVOT is the axis with movement of rotational and the bearing is the bearing surface. As a whole system of an implantable VAD should be made of long-life biomaterial so that there is no degradation or deformation during application time; surface modification techniques have been widely studied and implemented to improve properties such as biocompatibility and durability of applicable materials. The Chemical Vapour Deposition technique allows substrates having melting point higher than 300 °C to be coated, encapsulated, with a diamond like carbon film (DLC); The test simulated the actual conditions in which the system of support remains while applying a ADV. The results have been prepared on a comparative basis; where you select the pivoting assembly which showed less deformation by abrasive wear.

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Rosa Corrêa Leoncio de Sá, Vladimir Jesus Trava Airoldi, Tarcísio Fernandes Leão, Evandro Drigo da Silva, Jeison Willian Gomes da Fonseca, Bruno Utiyama da Silva, Edir Branzoni Leal, João Roberto Moro, Aron José Pazin de Andrade, Eduardo Guy Perpétuo Bock. 2015-11-01. In Vitro Durability - Pivot bearing with Diamond Like Carbon for Ventricular Assist Devices. https://arxiv.org/abs/1511.01357

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