Basic study of next generation axial flow blood pump to realize minimally invasive ventricular assist device by free-running in aorta

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K12792
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 90110:Biomedical engineering-related
• Research Institution: Tokai University
• Principal Investigator: Okamoto Eiji 東海大学, 生物学部, 教授 (30240633)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 人工心臓 / 補助循環 / 軸流血液ポンプ / 磁性流体

Outline of Final Research Achievements

In this study, we studied a catheter-mounted miniature axial flow blood pump placed at aortic valve position. We developed a miniature axial flow blood pump using a miniature magnetic fluid shaft seal, and the miniature magnetic fluid shaft seal composed a neodymium magnet ring, an iron ring, and a magnetic fluid particularly designed for artificial hearts. From FEM magnetic analysis, the magnetic fluid shaft seal has enough seal pressure for axial flow blood pumps. In in-vitro experiment using 40% glycerin solution as working fluid, the miniature axial flow blood pump has same pump performance as Impella 5.0 until 26000rpm, but it had motor output shortage above higher speed region.
Also we investigated pulsatility of blood circulation under left ventricular assistance using a axial flow blood pump placed at aortic valve position, and its magnitude of pulsatility is much higher than usual continuous flow blood pumps. Then it can serve more effective circulatory assistance.

Free Research Field

生体医工学

Academic Significance and Societal Importance of the Research Achievements

大動脈弁を貫通させ設置する超小型軸流血液ポンプの循環補助効果を，拍動流成分に着目し通常の連続流循環補助，回転数変調循環補助と比較し定量的に明らかにしたことに学術的意義がある．また，カテーテル設置式超小型軸流血液ポンプ開発のキーテクノロジーはモータへの血液流入を防ぐシール機構であるが，Imellaのシール機構であるパージシステムに代わり仕組み・構成が簡単な磁性流体軸シールで実現できることを示したことで，世界的にImpellaに代わる新たなカテーテル設置式軸流血液ポンプが促進され，それによりImpellaの課題を克服する新たなデバイスへの道を開いたことに学術的そして社会的意義がある．