New clinical failure mode triggered by a new coronary stent design

Abstract

Longitudinal stent compression (LSC) is a new failure mode not previously observed in coronary stents. This phenomenon occurs when the physician tries to cross the deployed stent with other devices. While this phenomenon has been observed with a number of stent designs, it seems more common with the Element stent. A computational LSC model using finite element analysis was developed. Computational simulations were performed on two representative coronary stents in the current market resembling Element and Endeavor in attempts to quantify individual contribution of the stent design pattern and connector number on LSC. Simulation results show that the connector number plays the most significant role in the development of the LSC issue. The LSC could be easily tripled for the Element stent simply by increasing the connector number from two to three. The stent design pattern plays a secondary role in LSC. The LSC could be improved by up to 30% when the design pattern changes from the offset peak-to-peak design (Element) to the peak-to-peak design (Endeavor). Conclusions obtained from this paper may help clinical stent selection and future stent design optimization to reduce the risk associated with longitudinal stent compression.