Analysis of rotary ventricular assist devices using CFD technique—A Review

With the increasing focus on reducing deaths because of heart ailments, considerable emphasis has been directed toward the development of ventricular assist devices (VADs) that work on the principle of mechanical pumps for supporting an infirm heart. The VADs are used primarily to assist the left ventricle, but their use has been extended for supporting the right ventricle as well as for supporting both ventricles simultaneously. In this connection, computational fluid dynamics (CFD) has evolved as an efficient technique for the design, development, evaluation, and optimization of VADs, enabling the prediction of operational characteristics of VADs as well as detailed global and local flow characteristics for an extensive set of working environments even before the manufacture and use of the actual device. CFD techniques yield valuable insight into the VADs’ effectiveness that enhances its operational behavior and decreases the risk associated with the use of the device, and at the same time decreases the manufacturing lead time and costs associated with the device. CFD has been quite beneficially used for the performance evaluation of VADs, but it still needs further development as hemolysis and thrombosis models cannot be easily integrated with the flow simulations. This review article presents abrief introduction to rotary VADs with a primary focus on the current status of CFD analysis of axial VADs, which provide the most suitable methods for computational design and optimization of VADs. It also identifies critical knowledge gaps and outlines the hematological models and the difficulties encountered in integrating them into CFD. Finally, future work based on the current scenario is also included.