RESUMO
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.
RESUMO
What started with 41 hospitalized patients identified as having laboratory-confirmed coronavirus disease 2019 (COVID-19) in Wuhan, China, by January 2, 2020, turned into an unprecedented pandemic with more than 113 million confirmed cases and a mortality exceeding 2.5 million deaths worldwide by the beginning of March 2021. Although the course of the disease is uneventful in most cases, there is a percentage of patients who become critically ill and need admission in the intensive care unit for severe respiratory failure. Numerous of these patients undergo invasive mechanical ventilation and have an extremely high mortality rate. For these patients, extracorporeal membrane oxygenation (ECMO) has emerged as a last standing resource. In the present study, the literature was reviewed to evaluate the worldwide data regarding the use of ECMO in the management of critically ill COVID-19 patients. ISI Thomson Web of Science was searched for articles with English language abstracts from inception to March 1, 2021, with 'ECMO in COVID-19' as key words. A total of 214 abstracts were screened (case reports, guidelines, reviews) and the most relevant articles were included in the present review. The use of ECMO in the management of critically ill patients with COVID-19-induced acute respiratory distress syndrome refractory to conventional mechanical invasive ventilation is increasing. By increasing the survival rate from less than 20% to more than 50%, ECMO proved to be a valuable resource in the management of the most challenging critically ill COVID-19 patients.