Oliveira Diana, Rosa Sílvia Aguiar, Tiago Jorge, Ferreira Rui Cruz, Agapito Ana Figueiredo, Sequeira Adélia
a Department of Mathematics and CEMAT , Instituto Superior Técnico, University of Lisbon , Lisbon , Portugal.
b Cardiology Department , Hospital de Santa Marta (CHLC) , Lisboa , Portugal.
Comput Methods Biomech Biomed Engin. 2019 Jun;22(8):815-826. doi: 10.1080/10255842.2019.1597860. Epub 2019 Apr 8.
Bicuspid aortic valve (BAV) aortopathy remains of difficult clinical management due to its heterogeneity and further assessment of related aortic hemodynamics is necessary. The aim of this study was to assess systolic hemodynamic indexes and wall stresses in patients with diverse BAV phenotypes and dilated ascending aortas. The aortic geometry was reconstructed from patient-specific images while the aortic valve was generated based on patient-specific measurements. Physiologic material properties and boundary conditions were applied and fully coupled fluid-structure interaction (FSI) analysis were conducted. Our dilated aortic models were characterized by the presence of abnormal hemodynamics with elevated degrees of flow skewness and eccentricity, regardless of BAV morphotype. Retrograde flow was also present. Both features, predicted by flow angle and flow reversal ratios, were consistently higher than those reported for non-dilated aortas. Right-handed helical flow was present, as well as elevated wall shear stress (WSS) on the outer ascending aortic wall. Our results suggest that the abnormal flow associated with BAV may play a role in aortic enlargement and progress it further on already dilated aortas.
由于二叶式主动脉瓣（BAV）主动脉病变具有异质性，其临床管理仍存在困难，因此有必要对相关主动脉血流动力学进行进一步评估。本研究的目的是评估不同BAV表型和升主动脉扩张患者的收缩期血流动力学指标和壁应力。根据患者特异性图像重建主动脉几何形状，同时根据患者特异性测量生成主动脉瓣。应用生理材料特性和边界条件，并进行完全耦合的流固相互作用（FSI）分析。无论BAV形态类型如何，我们的扩张主动脉模型的特征是存在异常血流动力学，具有较高程度的血流偏斜和偏心度。还存在逆向血流。通过血流角度和血流逆转率预测的这两个特征始终高于非扩张主动脉的报道值。存在右旋螺旋血流，以及升主动脉外侧壁上升高的壁面切应力（WSS）。我们的结果表明，与BAV相关的异常血流可能在主动脉扩张中起作用，并在已经扩张的主动脉上使其进一步发展。
