Goodin Mark S, Miyagi Chihiro, Kuban Barry D, Flick Christine R, Polakowski Anthony R, Karimov Jamshid H, Fukamachi Kiyotaka
Simu Tech Group Inc., Hudson, Ohio, USA.
Department of Biomedical Engineering, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA.
Artif Organs. 2025 Jan;49(1):52-64. doi: 10.1111/aor.14850. Epub 2024 Sep 5.
The left atrial assist device (LAAD) is a novel continuous-flow pump designed to treat patients with heart failure with preserved ejection fraction, a growing type of heart failure, but with limited device-treatment options. The LAAD is implanted in the mitral plane and pumps blood from the left atrium into the left ventricle. The purpose of this study was to refine the initial design of the LAAD, using results from computational fluid dynamics (CFD) analyses to inform changes that could improve hydraulic performance and flow patterns within the LAAD.
The initial design and three variations were simulated, exploring changes to the primary impeller blades, the housing shape, and the number, size, and curvature of the diffuser vanes. Several pump rotational speeds and flow rates spanning the intended range of use were modeled.
Guided by the insight gained from each design iteration, the final design incorporated impeller blades with improved alignment relative to the incoming flow and wider, more curved diffuser vanes that better aligned with the approaching flow from the volute. These design adjustments reduced flow separation within the impeller and diffuser regions. In vitro testing confirmed the CFD predicted improvement in the hydraulic performance of the revised LAAD flow path design.
The CFD results from this study provided insight into the key pump design-related parameters that can be adjusted to improve the LAAD's hydraulic performance and internal flow patterns. This work also provided a foundation for future studies assessing the LAAD's biocompatibility under clinical conditions.
左心房辅助装置（LAAD）是一种新型的连续流泵，旨在治疗射血分数保留的心力衰竭患者，这是一种日益增多的心力衰竭类型，但可用的装置治疗选择有限。LAAD植入二尖瓣平面，将血液从左心房泵入左心室。本研究的目的是优化LAAD的初始设计，利用计算流体动力学（CFD）分析结果来指导可能改善LAAD内水力性能和流动模式的改变。
对初始设计和三种变体进行了模拟，探索了主叶轮叶片、外壳形状以及扩散器叶片的数量、尺寸和曲率的变化。对跨越预期使用范围的几种泵转速和流量进行了建模。
在每次设计迭代获得的见解指导下，最终设计采用了相对于流入流具有更好对齐的叶轮叶片，以及更宽、更弯曲的扩散器叶片，这些叶片与来自蜗壳的接近流更好地对齐。这些设计调整减少了叶轮和扩散器区域内的流动分离。体外测试证实了CFD预测的修订后LAAD流路设计的水力性能改善。
本研究的CFD结果提供了对关键泵设计相关参数的见解，这些参数可进行调整以改善LAAD的水力性能和内部流动模式。这项工作还为未来评估LAAD在临床条件下的生物相容性的研究奠定了基础。
