Effect of different expansion strategies on coronary stent deployment in a tapered artery.

Abstract

Vascular stenting has been widely used to treat vessel stenosis. However, long-term successes of the procedure are often compromised by late stent thrombosis (ST) and in-stent restenosis (ISR), especially in tapered arteries. The aim of this study was to choose a reasonable expansion strategy for tapered arteries. A balloon-expandable coronary stent deployment in a tapered vessel was numerically studied fol-lowing three strategies: (i) selecting the proximal diameter of the tapered vessel as the reference diameter to expand the stent, (ii) selecting the middle diameter of the tapered vessel as the reference diameter to expand the stent, and (iii) selecting the distal diameter of the tapered vessel as the reference diameter to expand the stent. Computational results showed that the first expansion strategy resulted in the maximum vessel stress and the best stent apposition, while the third strategy resulted in the minimal vessel stress and the worst stent appo-sition. Meanwhile, the second expansion strategy achieved a trade-off between the first and third strategies, leading to acceptable vessel stress and stent apposition. The second expansion strategy is the most reasonable choice for tapered vessels, and it should be considered when implanting a stent.