Kawachi Y, Tokunaga K, Watanabe Y, Nose Y, Nakamura M
Ann Thorac Surg. 1985 May;39(5):456-61. doi: 10.1016/s0003-4975(10)61956-x.
Using a method of our own design, we evaluated intraoperatively the function of prosthetic heart valves. The changing hemodynamics induced by a stress test were assessed by simultaneously measuring the mean transvalvular pressure gradient and the stroke volume. The effective orifice area (EOA) of the valves was determined for each stroke by computer analysis, and this value was compared with the actual orifice area. Data were collected from 19 patients undergoing aortic or mitral valve replacement or both with 17 St. Jude Medical and 12 Ionescu-Shiley valves. The mean pressure gradient increased with tachycardia and an increase in mean left atrial pressure in the mitral position, but decreased with a decrease in cardiac output and peak left ventricular pressure in the aortic position. The St. Jude Medical valve had a smaller mean pressure gradient than the Ionescu-Shiley bioprosthesis. For both valves, the EOA increased with valve size. The St. Jude Medical valve had a greater EOA than the Ionescu-Shiley bioprosthesis, regardless of the valve size (p less than 0.005). However, the performance of prosthetic leaflets was better with the Ionescu-Shiley bioprosthesis than with the St. Jude Medical mechanical valve (p less than 0.001). This method involving computer analysis of each cardiac cycle proved to be useful for evaluating prosthetic heart valve function in the presence of changing hemodynamics.
我们采用自行设计的方法，在术中评估人工心脏瓣膜的功能。通过同时测量平均跨瓣压差和每搏量来评估应力测试所诱导的血流动力学变化。通过计算机分析确定每个心动周期瓣膜的有效开口面积（EOA），并将该值与实际开口面积进行比较。收集了19例接受主动脉瓣或二尖瓣置换术或两者皆有的患者的数据，其中使用了17个圣犹达医疗公司生产的瓣膜和12个伊奥内斯库 - 希利瓣膜。在二尖瓣位置，平均压差随心动过速和平均左心房压力升高而增加，但在主动脉位置，随心输出量降低和左心室压力峰值降低而降低。圣犹达医疗公司生产的瓣膜平均压差小于伊奥内斯库 - 希利生物瓣。对于这两种瓣膜，EOA均随瓣膜尺寸增大而增加。无论瓣膜尺寸如何，圣犹达医疗公司生产的瓣膜EOA均大于伊奥内斯库 - 希利生物瓣（p < 0.005）。然而，伊奥内斯库 - 希利生物瓣的人工瓣叶性能优于圣犹达医疗公司生产的机械瓣（p < 0.001）。这种对每个心动周期进行计算机分析的方法被证明对于评估血流动力学变化时人工心脏瓣膜功能是有用的。
