Abstract：
Subclinical valve thrombosis in heart valve prostheses is characterized by the progressive reduction in leaflet motion detectable with advanced imaging diagnostics. However, without routine imaging surveillance, this subclinical thrombosis may be underdiagnosed. We recently proposed the novel concept of a sensorized heart valve prosthesis based on electrical impedance measurement (IntraValvular Impedance, IVI) using miniaturized electrodes embedded in the valve structure to generate a local electric field that is altered by the cyclic movement of the leaflets. In this study, we investigated the feasibility of the novel IVI-sensing concept applied to biological heart valves (BHVs). Three proof-of-concept prototypes of sensorized BHVs were assembled with different size, geometry and positioning of the electrodes to identify the optimal IVI-measurement configuration. Each prototype was tested in vitro on a hydrodynamic heart valve assessment platform. IVI signal was closely related to the electrodes\' positioning in the valve structure and showed greater sensitivity in the prototype with small electrodes embedded in the valve commissures. The novel concept of IVI sensing is feasible on BHVs and has great potential for monitoring the valve condition after implant, allowing for early detection of subclinical valve thrombosis and timely selection of an appropriate anticoagulation therapy.
摘要：
心脏瓣膜假体中的亚临床瓣膜血栓形成的特征在于，先进的成像诊断可检测到的小叶运动逐渐减少。然而,没有常规影像学监测，这种亚临床血栓形成可能诊断不足.我们最近提出了基于电阻抗测量（瓣膜内阻抗，IVI）使用嵌入瓣膜结构中的小型化电极产生局部电场，该电场因瓣叶的循环运动而改变。在这项研究中,我们研究了新的IVI传感概念应用于生物心脏瓣膜(BHV)的可行性.传感器化BHV的三个概念验证原型被组装成不同的尺寸，电极的几何形状和定位，以确定最佳的IVI测量配置。在流体动力学心脏瓣膜评估平台上对每个原型进行体外测试。IVI信号与电极在瓣膜结构中的位置密切相关，并且在小电极嵌入瓣膜连合的原型中显示出更高的灵敏度。IVI传感的新概念在BHV上是可行的，并且在植入后监测瓣膜状况具有巨大潜力，允许早期发现亚临床瓣膜血栓形成并及时选择适当的抗凝治疗。
