搭桥冠脉内超声多普勒血流信号的仿真分析

Simulation Studies of Doppler Ultrasound Blood Flow Signals from Bypassed Coronary Arteries

为研究搭桥冠脉内血流状况与移植管结构因素的关系,采用基于计算流体动力学模型的信号仿真方法合成不同缝合角度、不同缝合距离的搭桥冠脉内的超声多普勒血流信号,并分析其频谱随两个结构因素变化的规律。结果表明:缝合角度越小,缝合前端及下游仿真信号的频谱宽度越小,说明搭桥手术的效果越好;缝合位置距离狭窄越近,缝合后端附近血流信号的频谱宽度越大,缝合前端及下游的频谱宽度则越小,说明手术应折中选取缝合位置。结论与血液动力学研究结果一致,可以为手术方案的设计和术后效果的监测提供参考。

To explore the correlation between blood flow conditions and geometric factors for a bypassed coronary artery, a simulation method based on the computational dynamics models is employed m generate the Doppler ultrasound blood flow signals from bypassed coronary arteries with different grafting angles and distances. The variation of the simulatod signal spectrum following that of the two factors is analyzed. Results show that the spectral bandwidth decreases with smaller angles at the toe and downstream of the anastomosis, thus the graft may have better post - operative effect. It is also seen that with a shorter grafting distance, the bandwidth increases near the heel of the anastomosis, however decreases at the toe and downstream area, which suggests a compmmise in positioning the graft. Since analysis results are consistent with the outcomes of hemodynamic studies, they may be helpful to the coronary bypass surgery planning and the evaluation of the post - operative effectiveness by the Doppler ultrasound technique.