Abstract 16160: Using Computational Fluid Dynamics and Imaging Registration Techniques to Identify Predictive Hemodynamic Factors of Aneurysmal Degeneration in Type B Aortic Dissection
Introduction: Progressive false lumen aneurysmal degeneration in type B aortic dissection (TBAD) is a complex process that is multi-factorial in etiology. Patient-specific computational fluid dynamics (CFD) simulations provide spatial and temporal hemodynamic quantities which facilitate the understanding of this disease progression.
Hypothesis: By combining comprehensive morphological changes obtained using the image registration (IR) method, correlations between hemodynamic factors and changes in the false lumen may be established.
Methods: Patient-specific CFD simulations were performed for the initial and four-year follow-up CT scans of a TBAD patient. Hemodynamic quantities, including wall shear stress and its gradient, time averaged wall shear stress and oscillatory shear index (OSI) were extracted from CFD simulations while a 3D deformation map between the initial and follow-up geometries was obtained using IR. Correlations between hemodynamic factors and the deformation map were analyzed.
Results: Deformation contours obtained by registering the follow-up false lumen to initial presentation are shown in Figure A. Maximum deformation was observed in the anterior region while maximum wall shear stress in both stages appeared at the entry tear (15.57 v.s. 15.08 Pa). The aorta on the initial scan had higher wall shear stress (at peak systole), wall shear stress gradient and time average wall shear stress on the false lumen (0.41 vs 0.07 Pa, 3.32 vs 0.18 Pa and 0.21 vs 0.08 Pa). In contrast, the averaged OSI was lower as compared to the follow up (0.12 vs 0.18), as shown in Figure B. Moreover, as shown in Figure A and B, a close correlation between OSI and deformation contours was observed.
Conclusions: OSI appears closely associated with false lumen degeneration in this patient. Further testing of this methodology may enable the use of CFD to predict which patients with complicated TBAD will develop late complication requiring surgical intervention.
Author Disclosures: H. Xu: None. B.G. Leshnower: Consultant/Advisory Board; Modest; Cryolife, Inc. M. Piccinelli: None. A. Veneziani: None.
- © 2016 by American Heart Association, Inc.