From the Department of Cardiovascular and Thoracic Surgery, University of Louisville, Louisville, Kentucky.
Department of Bioengineering, University of Louisville, Louisville, Kentucky.
ASAIO J. 2023 Jun 1;69(6):519-526. doi: 10.1097/MAT.0000000000001887. Epub 2023 Feb 10.
RT Cardiac Systems (RTCS, Raleigh, NC) is developing an intravascular percutaneous mechanical circulatory support (pMCS) device drive system for use during high-risk percutaneous coronary intervention and emergent cardiogenic shock. The proprietary pMCS device (US patent 10,780,206) consists of a miniaturized axial flow pump with an integrated motor connected via a short flexible drive system. This novel flexible drive system creates a flexible pump that is advantageous for percutaneous placement and conforming to anatomy. This design also has the benefit of not requiring a continuous external lubrication source. In this article, we present engineering development and feasibility testing of the prototype pMCS system. Computational fluid dynamics (CFD) modeling was performed to evaluate candidate blade set designs (impeller leading and trailing edges, diffuser) and predict hydrodynamic performance and hemolysis risk. Bench testing of candidate lip seal designs (radial interference, durometer, and seal angle) was evaluated for leak rate. Two 16Fr prototype devices were then fabricated and tested in a static mock flow loop. Experimental testing demonstrated 3 L/min flow against 110 mmHg and 4 L/min flow against 80 mmHg, which matched the CFD-predicted hydrodynamic performance. These results demonstrate feasibility of the engineering design and performance of the prototype devices.
RT 心脏系统公司(RTCS,罗利,北卡罗来纳州)正在开发一种用于高危经皮冠状动脉介入治疗和紧急心源性休克的血管内经皮机械循环支持(pMCS)装置驱动系统。专有的 pMCS 装置(美国专利 10,780,206)由一个带有集成电机的微型轴流泵组成,通过一个短的柔性驱动系统连接。这种新颖的柔性驱动系统创造了一种有利于经皮放置并与解剖结构相适应的柔性泵。这种设计还有一个好处,就是不需要连续的外部润滑源。在本文中,我们介绍了原型 pMCS 系统的工程开发和可行性测试。进行了计算流体动力学(CFD)建模,以评估候选叶片组设计(叶轮前缘和后缘、扩散器)并预测水动力性能和溶血风险。候选唇形密封设计(径向干涉、硬度和密封角)的台架测试评估了泄漏率。然后制造并在静态模拟流动回路中测试了两个 16Fr 原型装置。实验测试表明,在 110mmHg 下可达到 3L/min 的流量,在 80mmHg 下可达到 4L/min 的流量,与 CFD 预测的水动力性能相匹配。这些结果表明了工程设计和原型装置性能的可行性。