目的 探究心室内隧道(Intraventricular tunnel, IVT)构建术的补片形状对右心室双出口矫治术力学性能的影响。方法 基于理想化的IVT模型,设计二维IVT的补片。根据转弯部分菱形补片长短轴比的不同,建立了六组补片模型,利用有限元分析方法对补片的缝合、保持、撑起为三维IVT模型的过程进行数值模拟。结果 六组补片模型的缝合缘最大应力分别为：3.136 MPa、3.72 MPa、3.759 MPa、2.231 MPa、3.592 MPa、3.244 MPa,主要集中在转弯部分菱形锐角边缝合处；其构成的IVT体积分别为6504.24 mm3、6498.71 mm3、6502.36 mm3、6505.30 mm3、6507.28 mm3、6582.28 mm3；构成的IVT两端的压差为：8.35 mmHg、8.28 mmHg、7.9 mmHg、8.16 mmHg、8.27 mmHg、8.7 mmHg；流速分别为：1.67 m/s、1.666 m/s、1.627 m/s、1.647 m/s、1.669 m/s、1.7 m/s。结论 随着补片长短轴比例增大,IVT缝合缘最大应力先减少后增大,体积呈现增大的趋势,隧道两端的压差先减小后增大的趋势。菱形长短轴比为1:0.15的补片其表面应力分布均匀,且缝合缘上最大应力值最小,同时对右心室体积侵占较小,隧道两端的压差较小,缝合效果较好。
Objective Exploring the influence of the shape of the patch of the intraventricular tunnel (IVT) construction on the biomechanical performance of the double outlet right ventricle after correction. Methods Based on the idealized IVT model, a two-dimensional IVT patch was designed. Six groups of patch models were established according to the difference between the long and short axis of the rhombus patch in the turning part, and finite element analysis method was used to numerically simulate the process of stitching, holding and propping up the patch into a three-dimensional IVT model. Results The maximum stress of the suture line of the six groups of patch models are respectively 3.136 MPa, 3.72 MPa, 3.759 MPa, 2.231 MPa, 3.592 MPa, and 3.244 MPa, which are mainly concentrated at the acute-angle corners of the rhombus; the IVT volumes formed are respectively 6504.24 mm3, 6498.71 mm3, 6502.36 mm3, 6505.30 mm3, 6507.28 mm3, 6582.28 mm3; the pressure difference between the two ends of the IVT are respectively 8.35 mmHg, 8.28 mmHg, 7.9 mmHg, 8.16 mmHg, 8.27 mmHg, 8.7 mmHg; the flow rates are respectively 1.67 m/s, 1.666 m/s, 1.627 m/s, 1.647 m/s, 1.669 m/s, 1.7 m/s. Conclusions As the ratio of the long and short axis of the patch increases, the maximum stress of the IVT suture line first decreases and then increases, and the volume shows an increasing trend. The pressure difference between the two ends of the tunnel first decreases and then increases. The patch with the long-to-short axis ratio of 1:0.15 has a uniform surface stress distribution, and the maximum stress value on the suture line is the smallest. At the same time, the right ventricular volume is less encroached on, and the pressure difference at both ends of the tunnel is small, and the suture effect is better.