Identification of Inflating Pressure for a Diseased Artery During Stenting: FE Analysis

摘要

In coronary angioplasty a tubular stent is inserted in to a blocked artery and expanded at the blocked site to reinstate the blood flow. This treatment method has got wide acceptance since it is comparatively simple and fast curing. Atherosclerotic plaques are heterogeneous material with different mechanical behavior related to their composition and boundary conditions. It is not possible to conduct an in-vitro experiment to analyze the expansion behavior of a stent within the artery. However finite element method is a suitable tool widely used for this purpose. This paper study the expansion behavior of slotted tube stent in different cases (only stent, stent with balloon and stent within artery) using computational methods. The variation in stress distribution and expansion with respect to inflating pressure were compared. Significant difference was observed in the expansion behavior of stent with and without artery. An average of 10% reduction in the stress and 45% reduction in strain was noticed as stent expands inside the stenosed artery. Also the optimum pressure for the exact opening of a diseased artery was evaluated and observed that it varies with percentage of block and nature of plaque. An optimum pressure of 0.58MPa was identified for a diseased artery with 20.42% block to expand to its original diameter of 4mm.