Simulation of Degradation Process of Polymer Vascular Stent Using the Stochastic Finite Element Method
10.16156/j.1004-7220.2024.05.008
- VernacularTitle:利用随机有限元法模拟聚合物血管支架降解过程
- Author:
Wenjuan NIU
1
;
Peng ZHOU
;
Qiang WANG
Author Information
1. 西安建筑科技大学 冶金工程学院,陕西省冶金工程技术研究中心,西安 710055
- Keywords:
degradable polymer vascular stent;
degradation modeling;
non-uniform fragmentation;
molecular weight;
stress
- From:
Journal of Medical Biomechanics
2024;39(5):846-852
- CountryChina
- Language:Chinese
-
Abstract:
Objective To address the problem of late strut thrombosis generated after the implantation of biodegradable vascular stents,a stochastic finite element model was established to perform biomechanical analysis on the degradation process of polymer vascular stent from the perspectives of molecular weight and stress.Methods A mathematical model of the degradation process of biodegradable vascular scaffolds using poly lactic acid(PLA)was established and the mathematical model was imported,and a finite element model was constructed using COMSOL software.The model was stochastically used to analyze the effects on molecular weight and stress distribution in the degradation process under different stochastic parameters and standard deviations.Results During the degradation process of degradable polymer vascular scaffolds in human body,the random variables Mn0 and 8%standard deviation had the most significant effects on the distribution of molecular weights;randomization of the parameters led to a wider distribution range of the fracture strength during the degradation process of polymer vascular scaffolds,and the minimum value of fracture strength was lower.Conclusions The inhomogeneity of molecular weight distribution in polymer vascular stent materials leads to differences in mechanical properties at different locations of the stent,which in turn causes stress concentration within the material,ultimately leading to non-uniform fragmentation of the stent during degradation,which becomes a determining factor for stent thrombosis in later stages.This study provides theoretical guidance for designing next-generation biodegradable vascular stents.
