Um algoritmo baseado em otimização para construção de modelos de árvores arteriais com nexo em hemodinâmica computacional

Abstract

Computational modeling of blood flow in arterial trees of the circulatory system aims to understand this complex system, which can assist in the treatment of vascular diseases. Therefore, the construction of arterial tree models is mandatory to represent the vascular network in detail of anatomical domains with scarcity of morphometric data of the vessels. In the literature, there are the following classes of arterial trees models: anatomical, lumped parameter, fractal, and optimized. In the context of the optimized model, the models generated by the CCO (Constrained Constructive Optimization) method can reproduce of reproducing morphometric and hemodynamic characteristics of real arterial trees. This work proposes an algorithm based on the CCO method capable of generating models of arterial trees in 2D/3D domains not necessarily convex under the following conditions: fixed radius of the root segment, distinct flows in the terminal segments and different exponents in the bifurcation law during the growth of the tree. This algorithm is called VCCO (Variant of the Constrained Constructive Optimization). Morphometric data of the models generated by the algorithm were compared with real data from coronary artery trees. Regarding hemodynamics, vascular impedance in arterial tree models was calculated and compared with experimental and numerical data. Finally, pulsatile flow simulations were performed using an analytical method and arterial tree models as a geometric substrate. The morphometric and hemodynamic results obtained in this work agree with numerical and experimental data in the literature, which suggests that the algorithm VCCO produces reliable models that can be used in hemodynamic simulations.