Comparative study of the amount of backflow produced by four types of aortic valve prostheses.
Comparative study of the amount of backflow produced by four types of aortic valve prostheses.
复制标题
四种主动脉瓣假体产生回流量的比较研究。
DOI：
10.1115/1.3138459
复制
发表时间：
1984
期刊：
影响因子：
--
通讯作者：
Stein,PD
中科院分区：
文献类型：
--
作者：
Sabbah,HN;Stein,PD
To determine the extent of backflow encountered with currently used prosthetic valves, four types of aortic valves with comparable orifice diameters were tested in a pulse duplicating system. These were a Hancock porcine valve, a Lillehei-Kaster pivoting disk valve, a St. Jude bileaflet valve and a Bjo¨rk-Shiley tilting disk valve. Mean aortic pressure was sequentially increased from 83 to 147 mmHg, keeping the pump rate essentially constant (69–73 strokes/min). The porcine valve produced the least amount of total backflow (backflow due to closure plus leakage backflow) (1.6 to 2.4 mL/stroke). Among the mechanical valves the Bjo¨rk-Shiley valve showed the least amount of total backflow (5.0 to 6.0 mL/stroke). At a mean aortic pressure of 100 mmHg and a low cardiac output of 2 L/min, the total backflow with the porcine valve was only 6 percent of forward flow; whereas it was 19 percent with the Lillehei-Kaster valve, 22 percent with the St. Jude valve and 18 percent with the Bjo¨rk-Shiley valve. Leakage backflow at a given level of mean aortic pressure was, as expected, directly related to the annular clearance area. It is concluded that the Hancock valve showed the least amount of backward flow, which would be particularly beneficial in low output states. In the presence of normal hemodynamics, the amount of backflow with the three mechanical valves appeared to be well below the level of backflow considered to be clinically significant.
