Difference in hemodynamic and wall stress of ascending thoracic aortic aneurysms with bicuspid and tricuspid aortic valve

JOURNAL OF BIOMECHANICS

卷:46

Article

Pasta, Salvatore¹  Rinaudo, Antonino²  Luca, Angelo³  Pilato, Michele³  Scardulla, Cesare³  Gleason, Thomas G.⁴  Vorp, David A.⁵ 

[1] Fdn Ri MED, I-90133 Palermo, Italy

[2] Univ Palermo, Dipartimento Ingn Chim Gest Informat & Meccan, I-90128 Palermo, Italy

[3] Mediterranean Inst Transplantat & Adv Specialized, I-90127 Palermo, Italy

[4] Univ Pittsburgh, Dept Cardiothorac Surg, Pittsburgh, PA 15213 USA

[5] Univ Pittsburgh, Dept Bioengn, Pittsburgh, PA 15213 USA

关键词: Fluid-structure interaction;    Aortic dissection;    Ascending thoracic aortic aneurysm;    Bicuspid aortic valve;   

DOI  :  10.1016/j.jbiomech.2013.03.029

来源: Elsevier

【 摘 要 】

The aortic dissection (AoD) of an ascending thoracic aortic aneurysm (ATAA) initiates when the hemodynamic loads exerted on the aneurysmal wall overcome the adhesive forces holding the elastic layers together. Parallel coupled, two-way fluid structure interaction (FSI) analyses were performed on patient-specific ATAAs obtained from patients with either bicuspid aortic valve (BAV) or tricuspid aortic valve (TAV) to evaluate hemodynamic predictors and wall stresses imparting aneurysm enlargement and AoD. Results showed a left-handed circumferential flow with slower-moving helical pattern in the aneurysm's center for BAV ATAAs whereas a slight deviation of the blood flow toward the anterolateral region of the ascending aorta was observed for TAV ATAAs. Blood pressure and wall shear stress were found key hemodynamic predictors of aneurysm dilatation, and their dissimilarities are likely associated to the morphological anatomy of the aortic valve. We also observed discontinues, wall stresses on aneurysmal aorta, which was modeled as a composite with two elastic layers (i.e., inhomogeneity of vessel structural organization). This stress distribution was caused by differences on elastic material properties of aortic layers. Wall stress distribution suggests AoD just above sinotubular junction. Moreover, abnormal flow and lower elastic material properties that are likely intrinsic in BAV individuals render the aneurysm susceptible to the initiation of AoD. (C) 2013 Elsevier Ltd. All rights reserved.

【 授权许可】

Free