Lim Dohyung, Cho Seung-Kwan, Park Won-Pil, Kristensson Anders, Ko Jai-Young, Al-Hassani S T S, Kim Han-Sung
Department of Biomedical Engineering, Yonsei University, Wonju, Kangwondo, Republic of Korea.
Ann Biomed Eng. 2008 Jul;36(7):1118-29. doi: 10.1007/s10439-008-9504-1. Epub 2008 Apr 24.
The foreshortening or dogboning of a stent that occurs due to transient non-uniform balloon-stent expansion can induce a vascular injury, resulting in restenosis of the coronary artery. However, previous studies rarely considered the effects of transient non-uniform balloon expansion on analysis of the mechanical properties and behaviors of stents during stent deployment, nor did they determine design parameters to minimize the restenosis risk driven by foreshortening or dogboning. The aim of the current study was, therefore, to suggest potential design parameters capable of reducing the possibility of restenosis risk driven by foreshortening or dogboning through a comparative study of seven commercial stents using finite element (FE) analyses of a realistic transient non-uniform balloon-stent expansion process. The results indicate that using stents composed of opened unit cells connected by bend-shaped link structures, in particular the MAC Plus stent, and controlling the geometrical and morphological features of the unit cell strut or the link structure at the distal ends of stent may prevent restenosis risk caused by foreshortening or dogboning. This study provides a first look at the realistic transient non-uniform balloon-stent expansion by investigating the mechanical properties, behaviors, and design parameters capable of reducing the possibility of restenosis risk induced by the foreshortening or the dogboning.
由于短暂的非均匀球囊-支架扩张而导致的支架缩短或哑铃状变形，可引发血管损伤，进而导致冠状动脉再狭窄。然而，以往的研究很少考虑短暂的非均匀球囊扩张对支架植入过程中支架力学性能和行为分析的影响，也未确定能将由缩短或哑铃状变形引发的再狭窄风险降至最低的设计参数。因此，本研究的目的是，通过对七种商用支架进行有限元（FE）分析，模拟实际的短暂非均匀球囊-支架扩张过程，比较研究，从而提出能够降低由缩短或哑铃状变形引发的再狭窄风险可能性的潜在设计参数。结果表明，使用由弯曲形连接结构连接的开放单元细胞组成的支架，特别是MAC Plus支架，并控制单元细胞支柱或支架远端连接结构的几何和形态特征，可预防由缩短或哑铃状变形引起的再狭窄风险。本研究通过研究能够降低由缩短或哑铃状变形引发的再狭窄风险可能性的力学性能、行为和设计参数，首次审视了实际的短暂非均匀球囊-支架扩张情况。
