School of Electronic Information, Wuhan University, Wuhan, Hubei, 430072, People's Republic of China.
The First Affiliated Hospital of the University of Science and Technology of China, Hefei, Anhui, 230026, People's Republic of China.
Physiol Meas. 2023 Sep 22;44(9). doi: 10.1088/1361-6579/acd3d0.
A percutaneous left ventricular assist device (PLVAD) can be used as a bridge to heart transplantation or as a temporary support for end-stage heart failure. Transvalvularly placed PLVADs may result in aortic regurgitation due to unstable pump position during fully supported operation, which may diminish the pumping effect of forward flow and predispose to complications. Therefore, accurate characterization of aortic regurgitation is essential for proper modeling of heart-pump interactions and validation of control strategies.In the present study, an improved aortic valve model was used to analyze the severity of regurgitation produced by different pump position offsets. The link between pump position offset degree and regurgitation is validated in the fixed speed mode, and the influence of pump speed on regurgitation is verified in the variable speed mode, using the mock circulatory loop (MCL) experimental platform.The greater the pump offset and the more severe the regurgitation, the more carefully the pump speed needs to be managed. To avoid over-pumping, the recommended pump speed in this study should not exceed 30 000 rpm.The modeling approach provide in this study not only makes it easier to comprehend the impact of regurgitation events on the entire interactive system during mechanical assistance, but it also aids in providing timely alerts and suitable management measures.
经皮左心室辅助装置(PLVAD)可作为心脏移植的桥接治疗,或作为终末期心力衰竭的临时支持手段。由于在完全支持运行期间泵的位置不稳定,经瓣膜放置的 PLVAD 可能导致主动脉瓣反流,这可能会降低正向流动的泵送效果,并容易引发并发症。因此,准确描述主动脉瓣反流对于正确模拟心脏-泵相互作用和验证控制策略至关重要。
在本研究中,使用改进的主动脉瓣模型来分析不同泵位置偏移产生的反流严重程度。在固定速度模式下验证泵位置偏移程度与反流之间的关系,并在变速模式下使用模拟循环回路(MCL)实验平台验证泵速度对反流的影响。
泵偏移越大,反流越严重,就越需要仔细管理泵速。为避免过度泵送,本研究建议的泵速不应超过 30000rpm。
本研究中提出的建模方法不仅使我们更容易理解机械辅助过程中反流事件对整个交互系统的影响,还有助于提供及时的警报和适当的管理措施。