Development of evaluation system for artificial organs from the viewpoints of clinical study, engineering, and statistics.

为了从血流动力学的角度评估人工器官，如心室辅助系统、人工心脏瓣膜和动脉假体移植物，开发了一个循环模拟器。通过实验验证了用于右心室辅助系统的旋转泵和新设计的Y型主动脉假体在模拟器中的特性。结果表明，随着接枝流量的增加，枝径明显增加。本研究设计了一种新型的压力传感器和可膨胀管，用于临床应用。前者足够小，可以固定在可以测量压力的人造器官中。后者的设计是为了扩大管的直径作为气管管和左心室旁路插管。这些发明正在申请专利。此外，还开发了一个新的数据库系统，以便对临床数据进行统计分析。应用该系统对包括脉搏波速度（PWV）在内的临床数据进行实际分析，揭示了随着脉搏波速度（PWV）的增加，患者死亡风险增加的趋势。仿真器与数据库系统的结合将有助于从临床研究、工程和统计学的角度对人工器官进行评价。

A circulatory simulator was developed in order to evaluate artificial organs such as ventricular assist systems, artificial heart valves, and arterial prosthetic grafts from the view point of hemodynamics. Some experiments were conducted to demonstrate characteristics of a rotary pump used for a right ventricular assist system and a newly designed aortofemoral prosthetic Y graft in the simulator. As a result, it was revealed that there was definitely an incremental increase in the branch diameter increasing the flow rate through the graft. In this study, a newly designed pressure transducer and an expandable tube for clinical application were devised. The former is enough small to be fixed into artificial organs in which the pressure can be measured. The latter was designed to expand the diameter of the tube as a tracheal tube and a cannula for left ventricular bypass. These inventions are lodging patent applications. In addition, a new database system was developed in order to analyze clinical data statistically. Clinical data including pulse wave velocity (PWV) were analyzed actually by the system and it was revealed the tendency that the risk of the death increases accompanied by increase in PWV as a result. It is supposed that the combination of the simulator and the database system will be useful to evaluate artificial organs from the viewpoints of clinical study, engineering, and statistics.