Regional heterogeneity in left atrial stiffness impacts passive deformation in a cohort of patient-specific models

作者：Tiffany M G Baptiste, Cristóbal Rodero, Charles Sillett, Marina Strocchi, Christopher W. Lanyon, Christoph M. Augustin, Angela Lee, José Alonso Solís-Lemus, Caroline H. Roney, Daniel B. Ennis, Ronak Rajani, Christopher A. Rinaldi, Gernot Plank, R. Wilkinson, Steven E. Williams, Steven Niederer · 发表于：PLoS Computational Biology · 年份：2025 · DOI：10.1371/journal.pcbi.1013656 · 被引用次数：3 · 研究领域：Atrial Fibrillation Management and Outcomes、Cardiovascular Function and Risk Factors、Elasticity and Material Modeling

In atrial fibrillation (AF), atrial biomechanics are altered, reducing atrial movement. It remains unclear whether these changes are due to altered anatomy, myocardial stiffness, or constraints from surrounding structures. Understanding the causes of changed atrial deformation in AF could enhance tissue characterization and inform AF diagnosis, stratification, and treatment. We created patient-specific anatomical models of the left atrium (LA) from CT images. Passive LA biomechanics were simulated using finite deformation continuum mechanics equations. LA stiffness was represented by the Guccione material law, where α scaled the anisotropic stiffness parameters. Regional passive stiffness parameters were calibrated to peak regional deformation during the reservoir phase and validated against deformation transients derived from retrospective gated CT images during the reservoir and conduit phase. Physiological LA deformation varies regionally, with the roof deforming significantly less than other regions during the reservoir phase. The fitted model matched peak patient deformations globally and regionally with an average error of [Formula: see text] mm over our cohort. We compared deformation transients through the reservoir and conduit phases and found that the simulated deformation transients were within an average of [Formula: see text] mm per unit time of the CT-derived deformation transients. Regional stiffness varied across the atria with average α values of 1.8, 1.6, 2....