Yoganathan A P, Woo Y R, Sung H W, Williams F P, Franch R H, Jones M
J Thorac Cardiovasc Surg. 1986 Aug;92(2):198-209.
The in vitro hemodynamic characteristics of a variety of old and new generation porcine and bovine pericardial bioprostheses were investigated in the aortic position under pulsatile flow conditions. The following valves were studied: Carpentier-Edwards porcine (Models 2625 and 2650), Carpentier-Edwards pericardial, Hancock porcine (Models 242, 250, and 410), Hancock pericardial, and Ionescu-Shiley (standard and low-profile) bioprostheses. The pressure drop results indicated that the old design valves had performance indices in the range of 0.30 to 0.42, whereas the new low-pressure fixed designs have performance indices of 0.50 to 0.70. Flow visualization and velocity and turbulent shear stress measurements, conducted with a two-dimensional laser Doppler anemometer system, indicated that all tissue valve designs created jet-type flow fields. The intensity of the jets and turbulence levels were less severe with the new designs. The old designs created higher peak jet velocities and higher levels of turbulent shear stresses. On the whole, pericardial bioprostheses have better in vitro hemodynamic characteristics than porcine bioprostheses. These observations should have applications regarding the clinical choice of bioprosthetic valves and have implications regarding further improvements in the preparation and design of bioprosthetic valves.
在脉动流条件下，对多种新一代和旧一代猪心包及牛心包生物瓣膜在主动脉位置的体外血流动力学特性进行了研究。研究了以下瓣膜：卡朋蒂埃 - 爱德华兹猪瓣膜（型号2625和2650）、卡朋蒂埃 - 爱德华兹心包瓣膜、汉考克猪瓣膜（型号242、250和410）、汉考克心包瓣膜以及伊奥内斯库 - 希利（标准型和低剖面型）生物瓣膜。压降结果表明，旧设计瓣膜的性能指标在0.30至0.42范围内，而新的低压固定设计瓣膜的性能指标为0.50至0.70。使用二维激光多普勒风速仪系统进行的流动可视化以及速度和湍流剪切应力测量表明，所有组织瓣膜设计都会产生喷射型流场。新设计的喷射强度和湍流水平较低。旧设计产生更高的峰值喷射速度和更高水平的湍流剪切应力。总体而言，心包生物瓣膜比猪生物瓣膜具有更好的体外血流动力学特性。这些观察结果对于生物瓣膜的临床选择具有应用价值，并且对于生物瓣膜制备和设计的进一步改进具有启示意义。
