Impact of blood rheological strategies on the optimization of patient-specific LAAO configurations for thrombus assessment

Albors, Carlos; Olivares Miyares, Andy Luis; Iriart, Xavier; Cochet, Hubert; Mill, Jordi; Camara, Oscar

Impact of blood rheological strategies on the optimization of patient-specific LAAO configurations for thrombus assessment

Citation

Albors C, Olivares AL, Iriart X, Cochet H, Mill J, Camara O. Impact of blood rheological strategies on the optimization of patient-specific LAAO configurations for thrombus assessment. In: Bernard O, Clarysse P, Duchateau N, Ohayon J, Viallon M, editors. 12th International Conference, Functional Imaging and Modeling of the Heart, FIMH 2023; 2023 June 19-22; Lyon, France. Cham: Springer; 2023. p. 485-94. DOI: 10.1007/978-3-031-35302-4_50

Abstract

Left atrial appendage occlusion devices (LAAO) are a feasible alternative for non-valvular atrial fibrillation (AF) patients at high risk of thromboembolic stroke and contraindication to antithrombotic therapies. However, optimal LAAO device configurations (i.e., size, type, location) remain unstandardized due to the large anatomical variability of the left atrial appendage (LAA) morphology, leading to a 4–6% incidence of device-related thrombus (DRT). In-silico simulations can be used to estimate the risk of DRT and identify the critical parameters, such as suboptimal device positioning. However, simulation outcomes depend a lot on a series of modelling assumptions such as blood behaviour. Therefore, in this work, we present fluid simulations results computed on two patient-specific LA geometries, using two different commercially available LAAO devices, located in two positions: 1) mimicking the real post-LAAO intervention configuration; and 2) an improved one better covering the pulmonary ridge for DRT prevention. Different blood modeling strategies were also tested. The results show flow re-circulations at low velocities with significant platelet accumulation in LAA-deep device positioning uncovering the pulmonary ridge, potentially leading to thrombus formation. In addition, assuming Newtonian blood behaviour may result in an overestimation of DRT risk.

Description

Comunicació presentada a 12th International Conference, Functional Imaging and Modeling of the Heart, FIMH 2023, celebrada del 19 al 22 de juny de 2023 a Lió, França.