Lee Hwansung, Homma Akihiko, Tatsumi Eisuke, Taenaka Yoshiyuki
Department of Artificial Organs, Research Institute, National Cardiovascular Center, Suita, Osaka, Japan.
J Artif Organs. 2009;12(2):105-10. doi: 10.1007/s10047-009-0458-3. Epub 2009 Jun 18.
The aim of this study was to observe mechanical heart valve (MHV) cavitation pits resulting from in vivo testing of an electrohydraulic total artificial heart (EHTAH). During in vivo testing with three sets of valves (one set used in two animals), the slope of the driving pressure (left and right driving pressure) was used as a factor for investigating cavitation intensity, and the occurrence of cavitation was determined by the observation of cavitation pits on the explanted valve surfaces. Medtronic Hall valves were installed at the inlet and outlet positions of the two blood pumps. The EHTAH was tested using calves weighing 69-80 kg. The cavitation pits on the valve surface of the inlet valves of the left and right blood pumps were examined by scanning electron micrography. The driving pressure slope 5 ms before valve closure exceeded the cavitation threshold during in vitro testing. On both inlet valves, many large pits formed when the driving pressure slope was high and the pump operating time was long. When estimating cavitation intensity during in vivo testing, both a high driving pressure slope and a long operating time are important factors. The cavitation pits observed on the valve surfaces resulting from in vivo testing will eventually lead to leaflet fracture.
本研究的目的是观察电动液压全人工心脏（EHTAH）体内测试产生的机械心脏瓣膜（MHV）空化坑。在用三组瓣膜进行体内测试期间（一组用于两只动物），将驱动压力（左、右驱动压力）的斜率用作研究空化强度的一个因素，并通过观察取出瓣膜表面的空化坑来确定空化的发生情况。美敦力霍尔瓣膜安装在两个血泵的进出口位置。使用体重69 - 80千克的小牛对EHTAH进行测试。通过扫描电子显微镜检查左、右血泵进口瓣膜表面的空化坑。在体外测试期间，瓣膜关闭前5毫秒的驱动压力斜率超过了空化阈值。在两个进口瓣膜上，当驱动压力斜率高且泵运行时间长时，形成了许多大坑。在体内测试期间估计空化强度时，高驱动压力斜率和长运行时间都是重要因素。体内测试在瓣膜表面观察到的空化坑最终将导致瓣叶破裂。
