Most strokes in patients with atrial fibrillation (AF) are thought to arise from thrombus formation in the left atrial appendage (LAA). Assessing the hemodynamics in LAA and left atrium (LA) may provide some insights in the evaluation of the risk of thrombus formation. This study aims to find out the impact of different LAA locations with respect of LA on the risk of thrombus formation within LAA in patients with AF. Three different LAA locations at LA were modeled and a fully coupled fluid–structure interaction analysis was performed. A discrete phase method was used for particle residence analysis to evaluate risk of the thrombus formation. The results showed that LAA positions on the LA affected the LAA flow velocity distribution, passive contraction ability, and particle residence. In particular, the left pulmonary veins (PVs) had a greater influence on the LAA hemodynamics than the right PVs. The LAA had the lowest contractibility when it was located between left superior and left inferior PVs, and in this case, a larger number of particles were resided, which indicated a higher risk of thrombus formation. The present work provides a quantitative way to evaluate the risk of thrombus formation within LAA in patients with AF.

大多数心房颤动 (AF) 患者的中风被认为是由左心耳 (LAA) 血栓形成引起的。评估左心耳和左心房 (LA) 的血流动力学可能为评估血栓形成风险提供一些见解。本研究旨在了解 LA 的不同 LAA 位置对 AF 患者 LAA 内血栓形成风险的影响。对洛杉矶的三个不同的 LAA 位置进行了建模，并进行了完全耦合的流固耦合分析。离散相法用于颗粒驻留分析，以评估血栓形成的风险。结果表明，左心耳在左心房上的位置影响左心耳流速分布、被动收缩能力和颗粒停留。特别是，与右肺静脉相比，左肺静脉 (PV) 对左心耳血流动力学的影响更大。LAA 位于左上 PV 和左下 PV 之间时，其收缩性最低，并且在这种情况下，存在更多的颗粒，这表明血栓形成的风险更高。目前的工作提供了一种定量方法来评估 AF 患者 LAA 内血栓形成的风险。