Department of Cardiovascular Engineering, Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Pauwelsstraße 20, 52074, Aachen, Germany.
Department of Mechanical and Aerospace Engineering, Monash University, Clayton, VIC, 3800, Australia.
Biomed Eng Online. 2021 May 11;20(1):47. doi: 10.1186/s12938-021-00884-6.
Adverse neurological events associated with left ventricular assist devices (LVADs) have been suspected to be related to thrombosis. This study aimed to understand the risks of thrombosis with variations in the implanted device orientation. A severely dilated pulsatile patient-specific left ventricle, modelled with computational fluid dynamics, was utilised to identify the risk of thrombosis for five cannulation angles. With respect to the inflow cannula axis directed towards the mitral valve, the other angles were 25° and 20° towards the septum and 20° and 30° towards the free wall.
Inflow cannula angulation towards the free wall resulted in longer blood residence time within the ventricle, slower ventricular washout and reduced pulsatility indices along the septal wall. Based on the model, the ideal inflow cannula alignment to reduce the risk of thrombosis was angulation towards the mitral valve and up to parallel to the septum, avoiding the premature clearance of incoming blood.
This study indicates the potential effects of inflow cannulation angles and may guide optimised implantation configurations; however, the ideal approach will be influenced by other patient factors and is suspected to change over the course of support.
左心室辅助装置（LVAD）相关的不良神经系统事件被怀疑与血栓形成有关。本研究旨在了解植入装置方向变化时血栓形成的风险。使用计算流体动力学对严重扩张的脉动患者特定左心室进行建模，以确定五个插管角度的血栓形成风险。相对于朝向二尖瓣的流入插管轴，其他角度分别朝向间隔 25°和 20°以及自由壁 20°和 30°。
流入插管向自由壁倾斜导致血液在心室中的停留时间更长，心室冲洗速度更慢，沿间隔壁的脉动指数降低。根据模型，减少血栓形成风险的理想流入插管对准方式是朝向二尖瓣并与间隔平行，以避免过早清除进入的血液。
本研究表明了流入插管角度的潜在影响，并可能指导优化的植入配置；然而，理想的方法将受到其他患者因素的影响，并怀疑随着支持的进行而发生变化。
