Towards patient-specific hemodynamics of the aorta: A comprehensive CT-guided approach for moving boundary CFD simulations.
Authors
Affiliations (5)
Affiliations (5)
- BioCardioLab, Bioengineering Unit, Fondazione Monasterio, Massa, Italy; Department of Information Engineering, University of Pisa, Pisa, Italy.
- BioCardioLab, Bioengineering Unit, Fondazione Monasterio, Massa, Italy.
- Diagnostic Imaging, Department of Radiology, Fondazione Monasterio, Massa, Italy.
- IRCSS SYNLAB SDN, Naples, Italy.
- BioCardioLab, Bioengineering Unit, Fondazione Monasterio, Massa, Italy. Electronic address: [email protected].
Abstract
Numerical simulations play a key role in evaluating the hemodynamics of the thoracic aorta (TA). Common computational fluid dynamics (CFD) methods apply the rigid wall hypothesis, thus disregarding vessel deformation during the cardiac cycle; Fluid-Structure Interaction (FSI) approaches, while accounting for vessel compliance, demand extensive computational resources and rely on assumptions about wall mechanical properties. This study aims to develop a digital twin model of the aorta by implementing an AI-based framework for patient-specific moving boundaries, to be applied in CFD simulations (CFD<sub>MB</sub>) of the entire aorta. Starting from multi-phase ECG-gated CT scans, we built models of the TA and left ventricle (LV) at different phases of the cardiac cycle. An in-house non rigid-registration coupled with radial basis functions interpolation, was used to get iso-topological and mapped surface meshes at each phase. From the analysis of the LV volume changes during the cardiac cycle, patient-specific inlet condition was also applied. Results from CFD<sub>MB</sub> simulations were compared with those obtained from CFD. The CFD<sub>MB</sub> approach accurately captured TA morphological changes during the cardiac cycle, without compromising mesh quality. Differences in the main hemodynamic results were found between the two performed simulations strategies. The CFD<sub>MB</sub> approach also modeled the flow waveform shift that occurs along the TA lumen, enabling pulse wave velocity estimation. The implemented pipeline represents a promising method for patient-specific hemodynamic studies, overcoming the limitations of both conventional CFD and FSI simulations.