瓣膜高度对移植主动脉瓣开闭性能的影响

临床上治疗主动脉瓣膜关闭不全的的手术多采用瓣膜移植,但术后患者重建的主动脉根部存在扩张现象,因此瓣膜高度的不足会致使主动脉瓣膜再次关闭不全。本文研究不同主动脉瓣膜高度设计对瓣膜开闭性能的影响,通过体外数值模拟,获取最佳手术方案,提供技术支持和理论依据。本文以根部直径26.0 mm、瓣膜高度14.0 mm为参照,建立瓣膜高度增量为±0.5 mm的六组三维几何模型。通过对模型最大应力、瓣口面积和接触力等参数的结构力学计算和分析,获得合理的几何尺寸。研究发现,六组模型的最大应力值范围在640～690 kPa之间,与文献的结果相符合;瓣膜高度分别为13.5、14.0、14.5 mm的三组模型的瓣口面积在合理范围内;六组瓣叶接触力随瓣膜高度增加呈增大趋势。研究表明主动脉瓣膜的高度对主动脉瓣膜关闭性能存在影响,太小或太大的瓣膜高度会减小主动脉收缩期的瓣口面积,影响主动脉开闭功能。

Influence of valve height on the opening/closure performance of transplanted aortic valve

Valve transplantation is often used in the treatment of aortic valve insufficiency.However,after surgery,the reconstructed aortic roots have an expansion phenomenon,in which the lack of valve height causes the aortic valve to close again.In this paper,the effects of different aortic valve height design on valve opening and closing performance were studied.The optimal surgical plan was obtained by in vitro numerical simulation,providing technical support and theoretical basis.In this paper,six groups of three-dimensional geometric models with a valve height increment of±0.5 mm were established with a root diameter of 26.0 mm and a valve height of 14.0 mm.Through the structural mechanics calculation and analysis of the parameters such as maximum stress,valve area and contact force of the model,reasonable geometrical dimensions are obtained.The study found that the maximum stress values of the six groups of models ranged from 640 to 690 kPa,which was consistent with the results of the literature;the three-group models with valve heights of 13.5 mm,14.0 mm,and 14.5 mm were within a reasonable range.The contact force value of the 6 groups of leaflets increased with the increase of valve height.Studies have shown that the height of the aortic valve has an effect on the aortic valve closure performance.A valve height that is too small or too large will reduce the aortic systolic valve area and affect the aortic function.