A numerical study on the effect of geometrical parameters and loading profile on the expansion of stent

BACKGROUND: Stenting has been proposed as an effective treatment to restore blood flow in obstructed arteries by plaques. Although several modified designs for stents have been suggested, most designs have the risk of disturbing blood flow. OBJECTIVE: The main objective is to propose a stent design to attain a uniform lumen section after stent deployment. METHODS: Mechanical response of five different designs of J & J Palmaz-Schatz stent with the presence of plaque and artery are investigated; four stents have variable strut thickness of different magnitudes and the rest one is a uniform-strut-thickness stent. Nonlinear finite element is employed to simulate the expansion procedure of the intended designs using ABAQUS explicit. RESULTS: The stent design whose first cell thickness linearly increases by 35 percent, exhibits the best performance, that is it has the lowest recoiling and stress induced in the intima for a given lumen gain. It also enjoys the minimal discrepancy between the final at the distal and proximal ends. CONCLUSIONS: A uniform widened artery can be achieved by using the stent design with 35 percent increase in its first cell, which provides the possibility to prevent from disturbing blood flow and consequently post-operation complications.