摘要
目的通过数值模拟的方法对比分析端对边(end-to-side,ETS)与边对边(side-to-side,STS)两种不同搭桥方式的改良B-T手术(modified blalock-taussig shunt,MBTS)对血流动力学的影响,为临床治疗单心室心脏缺陷综合征提供参考。方法采集单心室心脏缺陷综合征病人的医学图像,重建病人心脏真实的几何模型;基于虚拟手术操作系统模拟手术过程;采集病人的生理数据,建立病人的集中参数模型(lumped parameter model,LPM);通过LPM计算提供计算流体力学(computational fluid dynamics,CFD)仿真模型的近生理边界条件;利用有限体积法对模型进行数值仿真。结果分别获取了ETS模型和STS模型的血液流速以及壁面切应力分布。ETS模型和STS模型的吻合口部位振荡剪切系数(oscillatory shear index,OSI)分别为3.058×10-3和13.624×10-3,能量损失分别为116.5和94.8 mW,右、左肺动脉流量比RRPA/LPA分别为0.8和1.72。结论两个模型的能量损失相差不大,对手术的影响相对较小。STS搭桥方式左右肺动脉流量分布均匀,吻合口位置OSI值较小,优于ETS搭桥方式,应着重考虑。本研究为临床治疗单心室心脏缺陷综合征提供重要的理论支持和参考。
Objective To analyze and compare hemodynamic features of two different options for modified B-T shunt （MBTS） surgery, namely end-to-side（ETS） and side-to-side （STS）, so as to provide references for clinical treatment of single ventricle heart defect syndrome. Methods The real geometric model was reconstructed by medical images obtained from a patient with hypoplastic left heart syndrome （HLHS）; MBTS surgery was simulated through virtual operations; a lumped parameter model （LPM） was constructed based on physiological data of the patient; the post-operational boundary conditions of computational fluid dynamics （CFD） models （namely STS model and ETS model） were predicted based on the LPM; numerical simulation was conducted on two CFD models by using finite volume method. Results Flow details and wall shear stress distributions were all obtained for two models. The mean oscillatory shear index （OSI） of ETS model and STS model in part of pulmonary arteries was 3.058×10-3 and 13.624×10-3, respectively, while the energy loss was 116.5 and 94.8 mW, respectively, and blood flow rate ratios of left pulmonary artery to right pulmonary artery （RRPA/LPA） were 0.8 and 1.72, respectively. Conclusions There were nearly no differences between two CFD models in energy loss, which led to a relatively small impact on the surgery. The STS model had a more balanced pulmonary artery blood perfusion and a smaller mean OSI in part of pulmonary arteries, therefore, the STS model was superior to the ETS model. This study provides an important theoretical support and reference for treating patients with HLHS.
出处
《医用生物力学》
EI
CAS
CSCD
北大核心
2014年第2期146-153,共8页
Journal of Medical Biomechanics
基金
国家自然科学基金资助项目(11172016)
高等学校博士学科点专项科研基金资助课题(20111103110012)
北京市自然科学基金重点项目(KZ20120005006)
关键词
血流动力学
计算流体动力学
集中参数模型
切应力
能量损失
Hemodynamics
Computational fluid dynamics （CFD）
Lumped parameter model （LPM）
Shearstress
Energy loss
