Abstract 14751: Everolimus-eluting Stents Demonstrate Better Vascular Healing and Function Compared to First-generation Drug-eluting Stents
Backgrounds Impaired arterial healing and abnormal vasomotor response after first-generation drug-eluting stents (DES) implantation have been reported. New-generation DES are expected to yield better biocompatibility than first-generation DES. We hypothesized that new-generation DES may demonstrate better vascular healing and function compared to first-generation DES.
Methods 63 patients treated with new-generation DES (everolimus-eluting stents; EES, n=20) and first-generation DES (sirolimus-eluting stents; SES, n=22 and paclitaxel-eluting stents; PES, n=21) were enrolled. All lesions were treated with a single stent. At 9 months after stent implantation, we tested endothelium-dependent and -independent vasomotions with intracoronary incremental dose of acetylcholine (Ach; 10-7mol/L and 10-6mol/L) and nitrate infusions. Vascular response was calculated by quantitative coronary angiography in proximal and distal segment to the stent and expressed as percent change versus baseline diameter. Additionally, we assessed neointimal coverage and existence of thrombi at the stent using coronary angioscopy. Neointimal coverage was classified into 4 grades from grade 0 (no neointima) to grade 3 (full coverage) as reported previously.
Results In-stent restenosis was not observed in any patients. In-stent late loss of EES (0.15±0.15mm) was similar to SES (0.24±0.29mm), but significantly smaller than PES (0.42±0.33mm vs. EES, p<0.05). In the distal segment to stent, vasoconstriction to maximum Ach dose in EES group was significantly smaller than SES or PES group, (EES: -15.9±10.7 vs. SES: -33.4±28.0%, p<0.05, EES vs. PES: -38.2±25.3%, p<0.05), but not in the proximal segment (NS). Endothelium-independent vasodilation didn't differ among the three groups. In angioscopic assessment, the grade of neointimal coverage was similar among the three groups (EES: 1.9±0.7 vs. SES: 1.5±0.7, NS, EES vs. PES: 1.6±0.8, NS). Thrombi inside the stent were significantly less in EES (5%, n=1) than in SES (31.8%, n=7, vs. EES, p<0.05) or in PES (66.7%, n=14, vs. EES, p<0.05).
Conclusions In conclusion, EES may be more preferable than first-generation DES considering better vasomotor responses and a low incidence of thrombus formation.
- © 2011 by American Heart Association, Inc.