冠動脈瘤治療における血流の数値流体力学解析

抄録

Coronary artery aneurysm (CAA) is an unusual disease whose incidence was reported as 0.14-4.9%. Currently, CAA usually is treated with coronary artery bypass grafting (CABG) surgery. However, there is limited evidence to prove which operation procedure, including bypass by saphenous vein graft (SVG) or left internal mammary artery (LIMA) with or without ligation of CAA, is better to treat this disease. At present, studies have shown that hemodynamic parameters are an important basis which can supply evidence to make the evaluation for different surgery. Therefore, we study the feasibility of different operating procedures from a hemodynamic point of view. Here we present four 3D models with coronary arteries and aortic arch named Model 1-4 (SVG/LIMA with CAA, SVG/LIMA without CAA, respectively). In order to reduce the computational requirements and obtain good boundary conditions, lumped parameter model (LPM, 0D model) coupled with 3D models. The mass-flow of SVG and LIMA, wall shear stress (WSS) and oscillatory shear index (OSI) were evaluated. Normal WSS and low OSI in grafting region appeared in Model 1, 3, and 4. Inverse flow, normal WSS, and high OSI put in an appearance on the LIMA in Model 2. Based on previous work, inverse graft flow and high OSI can make bypass graft invalid. Therefore, from a hemodynamic point of view, SVG and LIMA both can be used as the bypass graft to treat the CAA. However, CAA should be ligated when LIMA is used.