Niu Yudi, Sun Anqiang, Wang Zixuan, Yao Chenghong, Song Juxingsi
Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing 100083, China.
Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing 100083, China.
Cardiol Res Pract. 2020 Feb 25;2020:7041284. doi: 10.1155/2020/7041284. eCollection 2020.
Among the interventional stenting methods for treating coronary bifurcation lesions, the conventional treatments still have disadvantages, which include increased intervention difficulties or inadequate supply of blood flow to side branches and may alter the physiological function of downstream organs. Thus, the optimized design of stent geometry needs to be improved based on the specific shape of branches to minimize the complications of inadequate blood flow to the downstream organs and tissues. Our research used 3D modeling and fluid dynamics simulation to design and evaluate a new stent with locally enlarged segment by altering the proportion and length of enlarged surface area based on Bernoulli's equation. The aim is to increase the pressure and blood flow supply at side branches. According to series of blood flow simulations, the stent with 10% enlargement of surface area and length of 3 folders of stent diameter was assigned as the optimized design. The results revealed that by using this design, according to the simulation results, the average pressure on side branches increased at the rate of 43.6%, which would contribute to the adequate blood supply to the downstream organs. Besides, the average wall shear stress (WSS) at sidewalls increased at 9.2% while the average WSS on the host artery wall decreased at 14.1%. There is in the absent of noticeable rise in the total area of low WSS that blows the threshold of 0.5 Pa. Therefore, the present study provides a new method to optimize the hemodynamics features of stent for bifurcation arteries.
在治疗冠状动脉分叉病变的介入支架置入方法中，传统治疗仍存在缺点，包括增加介入难度、侧支血流供应不足，且可能改变下游器官的生理功能。因此，需要根据分支的具体形状改进支架几何结构的优化设计，以尽量减少下游器官和组织血流不足的并发症。我们的研究基于伯努利方程，通过改变扩大表面积的比例和长度，利用三维建模和流体动力学模拟来设计和评估一种具有局部扩大段的新型支架。目的是增加侧支的压力和血流供应。根据一系列血流模拟，将表面积扩大10%且长度为支架直径3倍的支架确定为优化设计。结果显示，采用该设计，根据模拟结果，侧支的平均压力以43.6%的速率增加，这将有助于向下游器官充分供血。此外，侧壁的平均壁面切应力（WSS）增加了9.2%，而主动脉壁上的平均WSS下降了14.1%。低于0.5 Pa阈值的低WSS总面积没有明显增加。因此，本研究提供了一种优化分叉动脉支架血流动力学特征的新方法。
