Rainer W G, Christopher R A, Golter L B, Sadler T R, Serkes K D
J Thorac Cardiovasc Surg. 1975 Oct;70(4):732-4.
Up to the present, stress forces on prosthetic heart valves have been studied primarily in an in vitro state and have been derived with a fair amount of estimation. Because of the practical and clinical implications, such as forces that may cause fabric wear or material deterioration, we felt that in vivo determination would be worthy of investigation. A microminiature strain gauge was secured to each leg of a non-cloth-covered prosthetic aortic valve and connected to a dual-beam oscilloscope. Strain measurements were first determined in a pulse duplicator with a blood analogue solution and physiological pressures and flow. The valve was also implanted into a dog in the subcoronary position and strain again measured. In vivo strain was found to be approximately 57 per cent of strain on a prosthetic aortic valve, in vitro, under the conditions of this experiment. This represents the first time that strain and force on a prosthetic aortic valve have been determined directly in the intact animal.
到目前为止，人工心脏瓣膜上的应力主要是在体外状态下进行研究的，并且是通过大量估算得出的。鉴于其实际和临床意义，比如可能导致织物磨损或材料劣化的力，我们认为体内测定值得研究。一个微型应变仪被固定在一个无布覆盖的人工主动脉瓣膜的每个瓣叶上，并连接到一个双光束示波器上。应变测量首先在一个配有血液模拟溶液以及生理压力和流量的脉动复制器中进行。该瓣膜也被植入到一只狗的冠状动脉下位置，并再次测量应变。在本实验条件下，发现体内应变约为体外人工主动脉瓣膜应变的57%。这是首次在完整动物体内直接测定人工主动脉瓣膜上的应变和力。
