Image-Based Flow Simulations of Pre- and Post-left Atrial Appendage Closure in the Left Atrium

Jia, Dongjie; Jeon, Bo-Young; Park, Hyung Bok; Chang, Hyuk Jae; Zhang, Lucy T.

doi:10.1007/s13239-019-00412-7

Cited by 28 publications

(25 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The SSR is a measurement of the flow velocity related to crossed space dimensions, and is linked to the rheological response as well as to thrombogenicity of blood (Cadroy et al, 1989;Ducci et al, 2016;Casa and Ku, 2017;Bosi et al, 2018). Although the velocity is the most used parameter to evaluate hemodynamics (Dedè et al, 2019;Jia et al, 2019;Masci et al, 2019), SSR is better descriptive of the flow features in a context where different global velocities are applied to the study chamber, due to the alternative LAA motion modes analyzed in this study. For the computation of the vortex structures, the Q-criterion was employed.…”

Section: Resultsmentioning

confidence: 99%

Effect of the Alterations in Contractility and Morphology Produced by Atrial Fibrillation on the Thrombosis Potential of the Left Atrial Appendage

Vella

Monteleone

Musotto

et al. 2021

Front. Bioeng. Biotechnol.

View full text Add to dashboard Cite

Atrial fibrillation (AF) is a common arrhythmia mainly affecting the elderly population, which can lead to serious complications such as stroke, ischaemic attack and vascular dementia. These problems are caused by thrombi which mostly originate in the left atrial appendage (LAA), a small muscular sac protruding from left atrium. The abnormal heart rhythm associated with AF results in alterations in the heart muscle contractions and in some reshaping of the cardiac chambers. This study aims to verify if and how these physiological changes can establish hemodynamic conditions in the LAA promoting thrombus formation, by means of computational fluid dynamic (CFD) analyses. In particular, sinus and fibrillation contractility was replicated by applying wall velocity/motion to models based on healthy and dilated idealized shapes of the left atrium with a common LAA morphology. The models were analyzed and compared in terms of shear strain rate (SSR) and vorticity, which are hemodynamic parameters directly associated with thrombogenicity. The study clearly indicates that the alterations in contractility and morphology associated with AF pathologies play a primary role in establishing hemodynamic conditions which promote higher incidence of ischaemic events, consistently with the clinical evidence. In particular, in the analyzed models, the impairment in contractility determined a decrease in SSR of about 50%, whilst the chamber pathological dilatation contributed to a 30% reduction, indicating increased risk of clot formation. The equivalent rigid wall model was characterized by SSR values about one order of magnitude smaller than in the contractile models, and substantially different vortical behavior, suggesting that analyses based on rigid chambers, although common in the literature, are inadequate to provide realistic results on the LAA hemodynamics.

show abstract

Section: Resultsmentioning

confidence: 99%

Effect of the Alterations in Contractility and Morphology Produced by Atrial Fibrillation on the Thrombosis Potential of the Left Atrial Appendage

Vella

Monteleone

Musotto

et al. 2021

Front. Bioeng. Biotechnol.

View full text Add to dashboard Cite

show abstract

“…Jia et al [11] proposed an automatic LAA segmentation method for the purpose of computational fluid dynamics (CFD) simulation. The method automatically detects a seed point in the LA by detecting the ascending and descending aorta in an axial view and utilizing the fact that the LA is located between them.…”

Section: Heuristics-based Segmentation Methodsmentioning

confidence: 99%

“…Jia et al [11] proposed a simulation framework which, using patient specific CT images, evaluates the clinical impact of the LAA, as well as the efficacy of the LAA closure. The framework implements an automatic LAA segmentation method, described in 2.1.…”

Section: D Laa Analysis Methods and Cfdmentioning

confidence: 99%

A Survey of Left Atrial Appendage Segmentation and Analysis in 3D and 4D Medical Images

Leventić¹,

Benčević²,

Babin³

et al. 2022

Preprint

View full text Add to dashboard Cite

Atrial fibrillation (AF) is a cardiovascular disease identified as one of the main risk factors for stroke. The majority of strokes due to AF are caused by clots originating in the left atrial appendage (LAA). LAA occlusion is an effective procedure for reducing stroke risk. Planning the procedure using pre-procedural imaging and analysis has shown benefits. The analysis is commonly done by manually segmenting the appendage on 2D slices. Automatic LAA segmentation methods could save an expert's time and provide insightful 3D visualizations and accurate automatic measurements to aid in medical procedures. Several semi-and fully-automatic methods for segmenting the appendage have been proposed. This paper provides a review of automatic LAA segmentation methods on 3D and 4D medical images, including CT, MRI and echocardiogram images. We classify methods into heuristic and modelbased methods, as well as into semi-and fully-automatic methods. We summarize and compare the proposed methods, evaluate their effectiveness, present current challenges in the field and approaches to overcome them.

show abstract

“…In [18], a comparison is made considering the differences deriving from applying or not an LES model in AF conditions; the results suggest that, also with a mesh that hasn't the fineness required for DNS, the absence of a turbulence model is acceptable in AF simulations. Due to the relevance of LAA in thrombus formation, many studies analysed how the geometrical morphology of this region of the LA affects the blood flow [28,29,30,31,32,33]. These works suggest the existence of a strong correlation between LAA morphology and thromboembolic risk; moreover, AF aggravates this danger.…”

Section: Introductionmentioning

confidence: 99%

Impact of Atrial Fibrillation on Left Atrium Haemodynamics: A Computational Fluid Dynamics Study

Corti¹,

Zingaro²,

Dedè³

et al. 2022

Preprint

View full text Add to dashboard Cite

We analyze left atrium haemodynamics, highlighting differences among healthy individuals and patients affected by atrial fibrillation. The computational study is based on patient-specific geometries of the left atria to simulate blood flow dynamics. We devise a novel procedure aimed at recovering the boundary conditions for the 3D haemodynamics simulations, particularly useful in absence of specific ones provided by clinical measurements. With this aim, we introduce a parametric definition of the atria displacement, and we employ a closed-loop lumped parameter model of the whole cardiocirculatory system conveniently tuned on the basis of the patient characteristics. We evaluate a number of fluid dynamics indicators for the atrial haemodynamics, validating our numerical results in terms of several clinical measurements; we investigate the impact of geometrical and clinical features on the risk of thrombosis. To analyse the correlation of thrombus formation with atrial fibrillation, coherently with the medical evidence, we propose a novel indicator, which we call age stasis and that arises from the combination of Eulerian and Lagrangian quantities. This indicator identifies regions where the slow flow cannot rinse the chamber properly, accumulating stale blood particles and creating optimal conditions for clot formation.

show abstract

Image-Based Flow Simulations of Pre- and Post-left Atrial Appendage Closure in the Left Atrium

Cited by 28 publications

References 42 publications

Effect of the Alterations in Contractility and Morphology Produced by Atrial Fibrillation on the Thrombosis Potential of the Left Atrial Appendage

Effect of the Alterations in Contractility and Morphology Produced by Atrial Fibrillation on the Thrombosis Potential of the Left Atrial Appendage

A Survey of Left Atrial Appendage Segmentation and Analysis in 3D and 4D Medical Images

Impact of Atrial Fibrillation on Left Atrium Haemodynamics: A Computational Fluid Dynamics Study

Contact Info

Product

Resources

About