Abstract 1952: Impact of Stent Dimension on Neointimal Hyperplasia within Zotarolimus Eluting Phosphorylcholine-Coated Cobalt-Chromium Alloy Stent: A 3-D IVUS Analysis
Objectives: Even in the drug-eluting stent era, smaller vessels are often associated with increased restenosis compared with larger vessels. The purpose of this study was to assess the potential influence of small stent size on neointimal suppression with zotarolimus eluting, phosphorylcholine-coated, cobalt-chromium alloy Driver™ stents (ZES).
Methods: From the Stanford University IVUS Core Laboratory database, 319 de novo coronary lesions with ZES implantation were enrolled into this volumetric IVUS analysis. The lesions were divided into 3 groups, based on stent volume index at 8-month follow-up: small (S: < 6 mm3/mm, n = 84), medium (M: 6–9 mm3/mm, n = 159), and large (L: > 9 mm3/mm, n = 76) stent groups. Mean neointimal thickness (NIT) was computed as (mean stent diameter minus mean lumen diameter)/2. Target lesion revascularization (TLR) at 9-month follow-up was also assessed in 3 groups.
Results: The stent lengths in small and medium ZES groups were significantly longer than that in large ZES (S: 24.57 ± 7.88 mm vs. M: 24.16 ± 6.62 mm, vs. L: 21.01 ± 4.76 mm, p = 0.0033 for S vs. L and P = 0.0031 for M vs. L). Follow-up IVUS showed that the NIT in small ZES was significantly smaller than those in medium and large ZES groups (S: 0.11 ± 0.08 mm vs. M: 0.14 ± 0.10 mm vs. L: 0.15 ± 0.11 mm, p = 0.0150 for S vs. M and P = 0.0205 for S vs. L). TLR was observed in 1 case (1.2%) in S group, 1 case (0.6%) in M group, and 2 cases (2.6%) in L group (P = NS).
Conclusion: Neointimal suppression with ZES may be significantly affected by stent size. Less neointimal thickness in smaller ZES, as compared to larger ZES, may in part account for favorable clinical outcomes of ZES.