NUMERICAL SIMULATION ON THE EFFECTS OF DRUG-ELUTING STENTS WITH DIFFERENT LINKS ON HEMODYNAMICS AND DRUG CONCENTRATION DISTRIBUTION

Abstract

The changes of hemodynamics and drug distribution caused by the implantation of drug-eluting stents (DES) have a significant influence on the in-stent restenosis. The present study numerically carried out a comparative study of hemodynamics and drug distribution using four different links of DES: Cordis BX velocity (Model A), Jostent flex (Model B), Sorin Carbostent (Model C), and DT-2 (Model D). The results showed that (1) low wall shear stress (WSS) distribution region spread widely in Model C (16.16%), with the least in Model B (10.35%); (2) Model C has relatively uniform drug concentration and causes of fewer low drug concentration region; and (3) Model A has the largest drug concentration, but also the most uneven distribution of drug. It was concluded that DES with circumferential links helps to improve in-stent restenosis as compared with that with longitudinal designs, and flexible links led to more uniformly and smoothly distributed blood flow than rigid links. However, the links with longitudinal designs had a better performance as drug release carrier than that with circumferential design. And if the links are too close together, the drug cannot be released effectively in the blood vessels. The current study helps to enhance our understanding of the performance of DES and provides assistance for optimal design and selection of DES.