Coronary restenosis after angioplasty has been reduced by stenting procedure, but in-
stent restenosis (ISR) has not been eliminated yet, especially in tortuous vessels. In this paper, we proposed a finite
element method (FEM) to study the expansion of a
stent in a curved vessel (the CV model) and their interactions. A model of the same
stent in a straight vessel (the SV model) was also studied and mechanical parameters of both models were researched and compared, including final lumen area, tissue
prolapse between
stent struts and stress distribution. Results show that in the CV model, the vessel was straightened by stenting and a hinge effect can be observed at extremes of the
stent. The maximum tissue
prolapse of the CV model was more severe (0.079 mm) than the SV model (0.048 mm); and the minimum lumen area of the CV was decreased (6.10 mm(2)), compared to that of the SV model (6.28 mm(2)). Tissue stresses of the highest level were concentrated in the inner curvature of the CV model. The simulations offered some explanations for the clinical results of ISR in curved vessels and gave design suggestions of the
stent and balloon for tortuous vessels. This FEM provides a tool to study mechanisms of
stents in curved vessels and can improve new
stent designs especially for tortuous vessels.