摘要
目的探讨新型“瓣中瓣”技术——经导管瓣中瓣对治疗“二次瓣膜病变”患者的有效性。方法以人体真实血流流量波形为基准,构建体外循环流动系统,采用粒子图像测速技术对人工心脏瓣膜下游血管内流场进行重构,在获取运动学信息的基础上引入时间平均壁面剪切应力、震荡剪切指数、相对停留时间等动力学参数,对经导管瓣中瓣以及经导管瓣膜的性能进行评估。结果分析心脏收缩早期、收缩峰值期、收缩晚期以及舒张早期四个特征状态,在流量较大时,经导管瓣中瓣会因诱发返流而导致一定程度的流动不稳定,但其性能总体上与经导管瓣膜相同,可在宽流量范围内正常使用。结论本文建立了一套有效的瓣膜下游流场动力学参数瓣膜性能体外评估体系,可对新型经导管瓣中瓣结构的适用性提供实验依据。
Objective To study the effectiveness of a new“valve-in-valve”technique—transcatheter valve-in-valve in the treatment of patients with“secondary valve replacement”.Methods Using true blood flow waveform based on the human body as a benchmark,an in vitro pulsatile circulation flow system was constrcted.Particle image velocimetry(PIV)was used to reconstruct the intravascular flow field downstream of the artificial heart valve.Then,based on the kinematics information,several dynamics parameters were induced,such as the time-averaged wall shear stress,oscillating shear index and relative residence time,combined with the clinical evaluation indices,such as the mean pressure difference and regurgitant fraction,to comprehensively evaluate the performance of the valve-in-valve and the single transcatheter valve.Results According to the analysis of the four characteristic states of early systolic,peak systolic,late systolic and early diastolic,when the flow rate was large,the valve-in-valve of the transcatheter valve would induce regurgitation and lead to a certain degree of flow instability,but its performance was generally the same as that of the transcatheter valve and could be used normally in a wide flow range.Conclusion In this paper,a set of effective evaluation system for valve performance of downstream flow field dynamics parameters in vitro was established,which can provide experimental basis for the applicability of the new valve-in-valve structure.
作者
刘丽
万辰杰
王硕
李崇崇
柯林楠
王春仁
LIU Li;WAN Chenjie;WANG Shuo;LI Chongchong;KE Linnan;WANG Chunren(Institute of Medical Device Testing,National Institutes for Food and Drug Control,Beijing 102629,China)
出处
《中国医疗设备》
2022年第5期45-50,55,共7页
China Medical Devices
关键词
粒子图像测速技术
体外循环系统
经导管瓣中瓣
流体动力学
particle image velocimetry
in vitro circulation system
transcatheter valve-in-valve
fluid dynamics
