Lee Hwansung, Homma Akihiko, Tatsumi Eisuke, Taenaka Yoshiyuki
Department of Artificial Organs, Research Institute, National Cardiovascular Center, Suita, Osaka, Japan.
J Artif Organs. 2010 Apr;13(1):17-23. doi: 10.1007/s10047-010-0490-3. Epub 2010 Feb 13.
Our group has developed an electrohydraulic total artificial heart (EHTAH) with two diaphragm-type blood pumps. Cavitation in a mechanical heart valve (MHV) causes valve surface damage. The objective of this study was to investigate the possibility of estimating the MHV cavitation intensity using the slope of the driving pressure just before valve closure in this artificial heart. Twenty-five and twenty-three-millimeter Medtronic Hall valves were mounted at the inlet and outlet ports, respectively, of both pumps. The EHTAH was connected to the experimental endurance tester developed by our group, and tested under physiological pressure conditions. Cavitation pits could be seen on the inlet valve surface and on the outlet valve surface of the right and left blood pumps. The pits on the inlet valves were more severe than those on the outlet valves in both blood pumps, and the cavitation pits on the inlet valve of the left blood pump were more severe than those on the inlet valve of the right blood pump. The longer the pump running time, the more severe the cavitation pits on the valve surfaces. Cavitation pits were concentrated near the contact area with the valve stop. The major cause of these pits was the squeeze flow between the leaflet and valve stop.
我们团队研发了一种带有两个隔膜式血泵的电动液压全人工心脏（EHTAH）。机械心脏瓣膜（MHV）中的气穴现象会导致瓣膜表面损伤。本研究的目的是探讨在这种人工心脏中，利用瓣膜关闭前驱动压力的斜率来估计MHV气穴强度的可能性。两个泵的进出口分别安装了25毫米和23毫米的美敦力霍尔瓣膜。EHTAH连接到我们团队研发的实验耐久性测试仪上，并在生理压力条件下进行测试。在左右血泵的进口瓣膜表面和出口瓣膜表面都能看到气穴坑。两个血泵中进口瓣膜上的坑比出口瓣膜上的更严重，并且左血泵进口瓣膜上的气穴坑比右血泵进口瓣膜上的更严重。泵的运行时间越长，瓣膜表面的气穴坑就越严重。气穴坑集中在与瓣膜限位器的接触区域附近。这些坑的主要原因是瓣叶与瓣膜限位器之间的挤压流。
