Otsuki Yosuke, Bui Minh Nhat, Ohtake Hiroshi, Watanabe Go, Matsuzawa Teruo
School of Information Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1211, Japan.
Department of Simulation Analysis, Fujitsu Systems East, 1415 Tsuruga Midori, Nagano 380-0813, Japan.
ScientificWorldJournal. 2013 Nov 17;2013:601470. doi: 10.1155/2013/601470. eCollection 2013.
Double aortic aneurysm (DAA) falls under the category of multiple aortic aneurysms. Repair is generally done through staged surgery due to low invasiveness. In this approach, one aneurysm is cured per operation. Therefore, two operations are required for DAA. However, post-first-surgery rupture cases have been reported. Although the problems involved with managing staged surgery have been discussed for more than 30 years, investigation from a hemodynamic perspective has not been attempted. Hence, this is the first computational fluid dynamics approach to the DAA problem. Three idealized geometries were prepared: presurgery, thoracic aortic aneurysm (TAA) cured, and abdominal aortic aneurysm (AAA) cured. By applying identical boundary conditions for flow rate and pressure, the Navier-Stokes equation and continuity equations were solved under the Newtonian fluid assumption. Average pressure in TAA was increased by AAA repair. On the other hand, average pressure in AAA was decreased after TAA repair. Average wall shear stress was decreased at the peak in post-first-surgery models. However, the wave profile of TAA average wall shear stress was changed in the late systole phase after AAA repair. Since the average wall shear stress in the post-first-surgery models decreased and pressure at TAA after AAA repair increased, the TAA might be treated first to prevent rupture.
双主动脉瘤（DAA）属于多发性主动脉瘤范畴。由于侵袭性低，修复通常通过分期手术进行。在这种方法中，每次手术治愈一个动脉瘤。因此，DAA需要进行两次手术。然而，已有首次手术后破裂病例的报道。尽管关于分期手术管理所涉及的问题已经讨论了30多年，但尚未尝试从血流动力学角度进行研究。因此，这是首次采用计算流体动力学方法解决DAA问题。准备了三种理想化几何模型：术前、胸主动脉瘤（TAA）治愈后和腹主动脉瘤（AAA）治愈后。通过对流量和压力应用相同的边界条件，在牛顿流体假设下求解纳维-斯托克斯方程和连续性方程。AAA修复后TAA的平均压力升高。另一方面，TAA修复后AAA的平均压力降低。首次手术后模型中的平均壁面剪应力在峰值处降低。然而，AAA修复后，TAA平均壁面剪应力的波形在收缩期末期发生了变化。由于首次手术后模型中的平均壁面剪应力降低，且AAA修复后TAA处的压力升高，可能应先治疗TAA以防止破裂。
