Long-term vascular responses to Resolute® and Xience V® polymer-based drug-eluting stents in a rabbit model of atherosclerosis
Faculty of Medicine and Health Sciences
Faculty of Pharmaceutical, Biomedical and Veterinary Sciences . Biomedical Sciences
Mount Kisco, N.Y.
Journal of interventional cardiology. - Mount Kisco, N.Y.
, p. 381-390
University of Antwerp
Objectives: To assess the late postinterventional response to iliac stenting in atheromatous rabbits using the Xience V everolimus-eluting stent (Xience V EES; Abbott Vascular) and the Resolute zotarolimus-eluting stent (Resolute ZES; Medtronic Vascular) with the MultiLink Vision bare metal stent (BMS; Abbott Vascular) as a reference. Background: Xience V EES and Resolute ZES were developed to overcome shortcomings of first-generation DES. Methods: Functional and microscopic changes were assessed by organ bath experiments and histopathologic examination. Gene expression was investigated using RT-PCR. Results: After 91 days, re-endothelialization was nearly complete (BMS: 93 +/- 3%; Resolute ZES: 92 +/- 2%; Xience V EES: 94 +/- 3%; P = 0.10). Neointima thickness was similar in Resolute ZES (0.17 +/- 0.08 mm) and BMS (0.17 +/- 0.09 mm), and reduced in Xience V EES (0.03 +/- 0.01 mm; P < 0.0001). Xience V EES had less peri-strut inflammation compared with BMS (P = 0.001) and Resolute ZES (P = 0.0001), while arterial segments distal to Xience VEES were more sensitive to acetylcholine than those distal to BMS and Resolute ZES (P = 0.02). Lectin-like oxidized receptor-1 was overexpressed in stented arteries (P < 0.001), whereas thrombomodulin was downregulated in Resolute ZES (P = 0.01) and BMS (P = 0.02) compared to unstented arteries of rabbits on regular chow. No significant changes were seen for vascular cell adhesion molecule-1, nitric oxide synthase 3, or endothelin-1. Conclusions: At 3-month follow-up, nearly complete re-endothelialization was achieved for all stent groups. Xience V EES induced greater suppression of neointimal growth and peri-strut inflammation, higher vasorelaxation to acetylcholine, and expression of thrombomodulin at the level of unstented controls.